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DS1307Z+ - 64 x 8 I2C RTC with 56B SRAM | Analog Devices
The Analog Devices DS1307Z+ is a 64 x 8 serial real-time clock with a 56-byte battery-backed nonvolatile SRAM, an I2C interface, and an 8-pin SOIC package. It tracks seconds, minutes, hours, day, date, month, and year in binary-coded decimal format, with leap-year compensation valid through 2100. The device is designed for low-power embedded systems that require timekeeping across power loss. A serial real-time clock is a clock-and-calendar integrated circuit that maintains wall-clock time independently of a processor. The DS1307Z+ belongs to the broader timekeeping and real-time-clock hierarchy, using a two-wire I2C bus to transfer addresses and data between the host controller and the RTC. Its 56-byte NV SRAM provides small nonvolatile storage alongside the calendar registers. The principal features include a 5 V supply application, 8-pin SOIC packaging, two-wire serial communication, 64 x 8 register organization, 56 bytes of battery-backed RAM, and automatic end-of-month date adjustment. The clock/calendar also includes programmable square-wave output capability according to the device documentation. The SOIC package is suitable for conventional surface-mount PCB assembly. The DS1307 architecture separates timekeeping from the host processor, allowing a microcontroller to read and write calendar data over I2C while the RTC continues counting from its external crystal timebase. The backup battery supplies the RTC and SRAM when the primary supply is removed. Applications should account for the device's 5 V operating context, crystal selection, pull-up requirements, and battery-backup implementation when laying out the board. Typical applications include industrial control panels, data loggers, embedded instruments, access-control terminals, and battery-backed embedded systems. The device is particularly useful when the system needs date and time persistence without maintaining a software clock during a complete power interruption. For designs using another RTC with a different pinout or supply requirement, compatibility must be verified rather than assumed. When laying out the PCB, keep the I2C traces short, provide the required bus pull-ups, place the crystal close to the device, and separate noisy switching or high-current paths from the timekeeping network. Verify the backup-battery circuit, initialization sequence, calendar limits, and square-wave configuration in firmware. This page combines verified manufacturer and distributor information with practical RTC design guidance. The DS1307Z+ is specifically identified by Analog Devices/Maxim Integrated as an 8-SOIC, 0.154-inch-width, 3.90 mm-width real-time clock. The verified distributor results list the part as a 56-byte I2C clock/calendar device with a list price starting from $2.39 on the manufacturer product page.
DS1307Z+T&R/C01 - 56B I2C RTC | Analog Devices
The Analog Devices DS1307Z+T&R/C01 is a low-power serial real-time clock and calendar with 56 bytes of nonvolatile SRAM, a 4.5 V to 5.5 V supply range, and an I²C interface in an 8-pin SOIC package. It stores seconds, minutes, hours, day, date, month, and year in binary-coded decimal format, while automatically adjusting the end-of-month date for months containing fewer than 31 days. The device also provides a programmable square-wave output according to the manufacturer product information. A real-time clock is an integrated circuit that maintains calendar time independently of the system processor. It belongs to the RTC and timekeeping IC hierarchy, where a clock/calendar supplies time and date information to embedded processing systems. A serial RTC combines this timekeeping function with a bidirectional bus such as I²C, allowing a microcontroller to read and write the clock registers and use the integrated SRAM for small quantities of retained data. The DS1307 combines a full BCD clock/calendar with 56 bytes of NV SRAM in one 8-SOIC device. Its I²C interface uses serial address and data transfer, while the available clock fields cover seconds through year. The manufacturer states that month-end dates are adjusted automatically, reducing the software required for common calendar corrections. The specified 4.5 V to 5.5 V operating supply also places the device in conventional 5 V embedded-system environments. The DS1307 is presented as a 64 × 8 serial I²C RTC in distributor documentation, while the underlying clock/calendar and 56-byte NV SRAM organization provides separate timekeeping and data-retention functions in the same package. Its 8-SOIC case, identified as 0.154 inch wide and 3.90 mm in body width, supports compact through-hole-style PCB assembly and conventional surface-mount reflow handling. The /C01 ordering suffix is associated with the supplied tape-and-reel product configuration. Typical uses include embedded data loggers, industrial controllers, consumer electronics, access-control equipment, and small systems that require persistent timestamps or a simple battery-backed calendar. It can also serve as a host-side real-time clock in a microcontroller design where the processor sleeps between tasks and must recover accurate elapsed and calendar information. The integrated SRAM offers limited data retention without adding a separate memory IC. Designers should verify the system bus pull-up arrangement, backup-battery behavior, and supply decoupling against the manufacturer datasheet before production release. The I²C lines and backup source must be arranged so normal supply transitions do not corrupt the clock/calendar or SRAM. Firmware should also verify the device address and the relationship between local time, UTC, daylight-saving rules, and the programmed calendar format. This product record combines the manufacturer product description, the DS1307 manufacturer datasheet link, and distributor evidence for the 56-byte NV SRAM, 4.5 V to 5.5 V supply, I²C interface, 8-SOIC package, date format, and current ordering configuration. It also distinguishes verified drop-in alternatives from superficially similar RTC devices that require different interfaces, packages, or pin assignments.
DS1307ZN+ - 56B I2C RTC with SRAM | Maxim Integrated
The Analog Devices Inc./Maxim Integrated DS1307ZN+ is a low-power serial real-time clock with a full binary-coded decimal clock/calendar and 56 bytes of nonvolatile SRAM. It uses a two-wire bidirectional I2C bus, provides 64 × 8 bits of register storage, and is packaged in an 8-pin SOIC measuring 0.154 inch, or 3.90 mm, wide. A real-time clock is a semiconductor timing component that maintains calendar information independently of the host processor. In the system hierarchy, an RTC belongs to clock and timing integrated circuits, alongside oscillators, timers, and frequency-control devices. The DS1307 records seconds, minutes, hours, day, date, month, and year while also exposing 56 bytes of battery-backed storage for alarms, configuration, or application data. Principal verified features include serial I2C address and data transfer, a 64 × 8 register map, 56 bytes of nonvolatile SRAM, and automatic end-of-month adjustment for months with fewer than 31 days. The manufacturer describes it as a full BCD clock/calendar. The integrated SRAM distinguishes it from RTCs that provide only calendar registers, while the serial interface allows a host microcontroller or processor to read and update time without using many parallel pins. The device combines timekeeping and small amounts of persistent configuration storage in one compact IC. Its clock/calendar registers expose standard time information, while SRAM bytes can retain settings when the system loses its main supply, provided the RTC backup supply remains available. Exact electrical limits, oscillator accuracy, voltage range, current consumption, alarm behavior, and square-wave timing require confirmation from the complete manufacturer datasheet. Typical uses include industrial controllers, embedded data loggers, building equipment, access-control terminals, connected sensors, and legacy computer systems that retain an I2C host interface. A microcontroller reads the BCD calendar through the serial bus and can use the SRAM for small configuration records. Firmware must convert BCD values into binary or decimal and detect month rollover at the end of shorter months. Designers should confirm the backup-battery implementation, logic levels, address selection, pull-up arrangement, and decoupling against the manufacturer datasheet before layout release. The I2C bus requires suitable pull-ups, while the 8-SOIC footprint requires a land pattern matching the 3.90 mm-wide body. Do not infer oscillator accuracy or retention duration from the RTC category; those values must be verified for the selected production variant. This page consolidates the official DS1307 description, distributor package information, verified sourcing links, and engineering selection guidance. It also separates confirmed facts from parameters requiring verification, helping engineers evaluate the DS1307ZN+ without confusing a functionally similar RTC with a guaranteed pin-to-pin replacement.
DS1307ZN+T&R - I2C RTC with 56B SRAM | Analog Devices
The Analog Devices DS1307ZN+T&R is a low-power serial real-time clock and calendar with 56 bytes of nonvolatile SRAM, housed in an 8-pin SOIC package rated for a 5.5 V maximum supply. It maintains seconds, minutes, hours, day, date, month, and year information while communicating with a host through a bidirectional two-wire I2C bus. The DS1307ZN+T&R is supplied in tape-and-reel packaging for automated assembly. A real-time clock is a timekeeping integrated circuit that preserves calendar information when the main system is unpowered. The broader hierarchy is RTC -> serial clock/calendar -> timing IC -> semiconductor. Unlike a microcontroller software timer, the DS1307ZN+T&R continues tracking time independently, making it useful for data logging, industrial controllers, embedded products, and systems that require timestamps after reset or power interruption. The principal feature is the combination of BCD clock/calendar data and 56 bytes of NV SRAM in one compact device. The calendar automatically adjusts the end-of-month date for months with fewer than 31 days. The I2C interface reduces the number of host connections compared with a parallel real-time clock, while the 8-pin SOIC package supports conventional surface-mount manufacturing. The verified distributor description identifies the interface as 2-wire serial I2C and the memory as 56 bytes. The DS1307 uses a serial architecture in which address and calendar data are transferred over the same two-wire bus. Host firmware writes control and calendar registers or reads the current time, while the SRAM provides compact nonvolatile storage for alarms, counters, configuration data, or small log fragments. Its low-power design makes it appropriate for embedded systems in which the host is frequently powered down but wall-clock continuity remains valuable. Typical implementations include industrial data loggers, building-control equipment, consumer appliances, metering systems, and microcontroller-based embedded products. In each case, the RTC acts as the authoritative low-power time source while the host handles calculations, communications, user interaction, and higher-level control. The integrated SRAM can retain small configuration records without adding a separate external memory component. PCB design should preserve the exact 8-pin SOIC footprint and route the I2C lines as a properly terminated bus. The verified source set does not provide detailed pin names, crystal configuration, capacitor values, or electrical limits, so those design details must be confirmed in the current Analog Devices or Maxim Integrated manufacturer datasheet before layout and firmware are released. This page consolidates the verified manufacturer description, distributor records, package information, functional alternatives, and application guidance. It also distinguishes verified capabilities from parameters that still require datasheet confirmation, helping engineers evaluate the DS1307ZN+T&R without assuming unsupported electrical specifications.
DS1307ZN+T&R/C02 - 56B I2C RTC | Maxim Integrated
The Analog Devices Inc./Maxim Integrated DS1307ZN+T&R/C02 is a low-power, serial real-time clock and calendar with 56 bytes of nonvolatile SRAM, a 4.5 V to 5.5 V supply range, and an I2C interface in an 8-pin SOIC package measuring 0.154 inch, or 3.90 mm, wide. The device maintains seconds, minutes, hours, day, date, month, and year information while automatically adjusting the end-of-month date for months containing fewer than 31 days. A real-time clock is a timekeeping integrated circuit that continues tracking calendar time independently of the host processor's main clock. The DS1307 belongs to the hierarchy of clock and timing integrated circuits, serial real-time clocks, and battery-backed timekeeping devices. Unlike a simple counter or digital display, it provides decoded calendar data, programmable clock and calendar registers, and 56 bytes of SRAM for application-specific data. Key features include a low-power BCD clock and calendar, 56 bytes of NV SRAM, a two-wire bidirectional I2C serial interface, and operation from 4.5 V to 5.5 V. The manufacturer describes the time format as HH:MM:SS in either 12-hour or 24-hour operation, while the date format is YY-MM-DD-dd. Calendar information includes seconds, minutes, hours, day, date, month, and year. The device is accessed through a serial I2C bus, allowing the host controller to read or update time while using pull-up resistors on the bus. The clock/calendar section and the 56-byte NV SRAM share the same serial interface. This integration reduces the number of external timing components required in embedded systems while retaining battery-backed state when the system supply is removed. Typical uses include embedded instrumentation, industrial control panels, data-acquisition equipment, consumer appliances, and microcontroller systems that require a calendar timestamp after power loss. The same physical 8-SOIC footprint can simplify prototype transitions to a qualified PCB layout, although pull-up placement, backup-battery compatibility, oscillator stability, and decoupling remain application-specific concerns. The primary design consideration is preserving clean I2C communication while the RTC operates from a 5 V rail. Keep the I2C pull-ups and decoupling capacitors close to their associated devices, confirm that the host logic levels are compatible with the bus, and provide the backup source required by the application. Review the manufacturer datasheet before finalizing the crystal, backup-cell, and layout implementation. This page consolidates the verified manufacturer and distributor information for the DS1307ZN+T&R/C02, adds practical RTC design guidance, and clearly identifies where package, pinout, temperature, pricing, and lifecycle details still require verification.
DS1338C-18# - I2C RTC with 56-Byte NV RAM | Analog Devices
The Analog Devices DS1338C-18# is a low-power serial real-time clock and calendar with 56 bytes of nonvolatile SRAM, an I2C interface, and a 16-pin SOIC package. The device provides full binary-coded decimal clock and calendar registers covering seconds, minutes, hours, day, date, month, and year, while maintaining time across power interruptions through its backup supply path. Its 16-SOIC package is identified by DigiKey as measuring 0.295 inches, or 7.50 mm, in width. A real-time clock is a timekeeping integrated circuit that maintains calendar information independently of a system’s main processor. In the electronic-component hierarchy, an RTC belongs to clock and timing integrated circuits and provides a dedicated time base for data logging, control, communications, and embedded systems. Unlike a software clock calculated by a microcontroller, this RTC can continue tracking elapsed time while the host is reset, asleep, or disconnected from its main power rail. The DS1338C-18# combines a serial RTC with 56 bytes of nonvolatile SRAM. The clock/calendar automatically adjusts the end-of-month date for months containing fewer than 31 days. Address and data transfer through the I2C interface, allowing the host processor to read calendar data and access the auxiliary SRAM over the same two-wire bus. This integration reduces the number of separate serial components required in compact embedded designs. The verified product information identifies the part as an industrial-temperature, gull-wing terminal, 16-terminal SOP package. It is specified for use with I2C-compatible controllers and is suited to systems requiring persistent timestamps, alarm functions, periodic scheduling, or limited configuration storage. The nonvolatile SRAM provides 56 bytes for counters, calibration values, serial identifiers, operating flags, or other small records that must survive a reset and power loss. Because the RTC communicates over a shared two-wire bus, correct pull-up resistor selection and bus timing are central to implementation. The host must also distinguish the RTC’s calendar registers from the SRAM addresses and preserve adequate decoupling near the device. Reviewing the DS1338C datasheet and the specific ordering suffix ensures that supply configuration, temperature grade, and package interpretation match the assembled board. This product page combines verified distributor and manufacturer information, technical application guidance, parameter comparisons, and practical replacement considerations. It is intended to support component selection, schematic review, sourcing, and PCB design without substituting a generic RTC for a verified pin-compatible device.
DS1338C-3# I2C RTC with 56-Byte NV RAM | Analog Devices
The Analog Devices DS1338C-3# is a low-power I2C real-time clock with a full BCD clock/calendar, 56 bytes of nonvolatile SRAM, and a 16-pin SOIC package. According to the verified manufacturer listing, it operates from 2.7V to 5.5V and transfers address and data through a two-wire serial interface. The -3 suffix identifies the verified DS1338C-3 ordering variant, while the complete ordering code includes the # package and finish designation. A real-time clock is a timekeeping integrated circuit that maintains calendar information when the main system clock is unavailable. Within the hierarchy of semiconductors, an RTC is a clock and timing IC, while the DS1338C adds digital data storage and serial host communication. This combination makes it useful for systems that need wall-clock timestamps, event scheduling, traceable boot records, or configuration retention during power interruptions. The verified device information identifies seconds, minutes, hours, calendar data, I2C address and data transfer, 56-byte NV SRAM, and a 2.7V-to-5.5V supply range. Its NV memory can retain application data while the RTC supplies time and calendar information. Because both functions use one compact 16-pin SOIC device, a board can reduce its component count compared with separate RTC and memory packages. The I2C interface allows a host microcontroller to read and write the clock/calendar and access the NV SRAM through serial transactions. Firmware must implement the device's register map, address conventions, and access sequence exactly as described in the manufacturer datasheet. The verified product data does not provide a complete timing table, oscillator calibration value, temperature range, or absolute maximum ratings, so those values must be verified before design release. Typical uses include industrial controllers, data loggers, metering equipment, embedded instruments, and compact consumer products that retain timestamps or small configuration records. The DS1338C-3# is especially appropriate when the system already supports I2C and needs a dedicated timekeeping device rather than deriving time solely from a host microcontroller. For a new PCB, preserve the manufacturer's recommended I2C pull-up arrangement, power decoupling, crystal connection, and exposed-pad requirements where applicable. Confirm the exact DS1338C-3# datasheet, package drawing, and ordering information before layout. This page synthesizes the verified device identity, distributor listing data, package information, and design guidance without inventing unprovided electrical values.
DS1338C-33# - 56-Byte NV RAM I2C RTC | Analog Devices
Analog Devices DS1338C-33# is a low-power serial real-time clock and calendar with 56 bytes of nonvolatile SRAM, 2-wire I2C communication, and a 16-SOIC package. The device maintains seconds, minutes, hours, day, date, month, and year information in binary-coded decimal format while providing serial access to its clock/calendar registers and onboard storage. A real-time clock is a clock and timing IC that maintains time independently of the host processor or system clock. Within the broader semiconductor hierarchy, an RTC belongs to the clock and timing category, sits below timekeeping integrated circuits, and supports embedded systems that require accurate calendar information after reset, power interruption, or loss of system time. The DS1338C-33# combines this timekeeping function with 56 bytes of NV SRAM for retaining small quantities of configuration or system data. The verified product information identifies an I2C interface, 56-byte NV RAM, full BCD clock/calendar functionality, and automatic end-of-month date adjustment. Its serial interface reduces the number of signal connections required compared with a parallel real-time clock. The clock/calendar records seconds through years, allowing a host microcontroller to query or update time while leaving periodic timekeeping in the dedicated RTC. The DS1338C-33# is housed in a 16-SOIC package measuring 0.295 inch wide by 7.50 mm as identified in the distributor listing. Its surface-mount construction supports compact embedded assemblies while allowing automated production. The low-power architecture is appropriate for systems that must preserve time and small data records without continuously operating the main processor. Typical uses include industrial embedded controllers, data-acquisition equipment, connected products, and systems that need an independent time base across resets. It can also serve as a companion timekeeper for a microcontroller-based product while its NV RAM stores limited configuration state. Host firmware must implement the device's register map, I2C address, time format, and any alarm or square-wave functions required by the design. Designers should verify the complete pin assignment, electrical limits, timing characteristics, oscillator configuration, backup-battery behavior, and recommended decoupling directly against the Analog Devices DS1338 datasheet before layout. A crystal and suitable load components are generally required for accurate timekeeping, while I2C traces should be kept short and the power rails properly decoupled. This page consolidates the verified manufacturer and distributor information, prices as of 2026-10-28, package details, sourcing links, and selection guidance. It also distinguishes verified drop-in candidates from unverified cross-brand options and flags specification fields that require confirmation from the manufacturer datasheet.
DS1338C-33#T&R - 3.3V I2C RTC with 56B NV RAM | ADI
The Analog Devices Inc./Maxim Integrated DS1338C-33#T&R is a 3.3 V serial real-time clock and calendar with 56 bytes of nonvolatile SRAM, an I2C two-wire serial interface, and a 16-pin SOIC package. It supplies calendar and time information including seconds, minutes, hours, day, date, month, and year while operating from a 3 V to 5.5 V supply. The -33 designation identifies the 3.3 V configuration, and the T&R suffix denotes tape-and-reel ordering. A real-time clock, or RTC, is a clock-and-timing IC that maintains time independently of the host processor or system clock. Its place in the broader hierarchy is RTC → serial RTC → clock and timing IC → integrated circuit. The DS1338 stores its time and calendar data in binary-coded decimal form, automatically adjusts the end-of-month date for months with fewer than 31 days, and supports leap-year information through its clock/calendar functions. The principal feature of the DS1338C-33#T&R is the combination of a complete calendar clock and 56 bytes of battery-backed nonvolatile memory in one serial device. The I2C interface transfers both address and data over two wires, reducing the pin and routing burden compared with a parallel RTC. Additional documented functions include a square-wave output, leap-year handling, and automatic month-end adjustment. The specified operating supply range is 3 V to 5.5 V, while the backup battery input accepts 1.3 V to 3.7 V. The device is designed for low-power timekeeping, with a verified timekeeping current range of 125 µA to 200 µA. Its backup supply allows the clock and calendar, as well as information retained in the nonvolatile memory, to continue operating when the main supply is absent, subject to the device-specific backup implementation. The 16-pin SOIC package supports conventional surface-mount assembly and provides separate access for serial data, timekeeping crystals, supplies, reset, and square-wave functionality, although the supplied source excerpts do not include the complete pin map. Typical uses include industrial embedded systems, data-logging equipment, metering products, medical instruments, and networked embedded controllers. The 56-byte NV SRAM is useful for small pieces of persistent information such as counters, calibration flags, calibration offsets, event counters, or configuration records. The 3.3 V configuration is particularly appropriate for systems whose logic rails operate at 3.3 V, while the 3 V to 5.5 V main supply range provides flexibility across mixed-voltage equipment. When designing around this RTC, budget for the exact crystal load capacitance and layout recommended by the manufacturer, and verify startup behavior across the complete temperature range. The I2C pull-up network must tolerate the active bus voltage, while the backup cell or supply path requires careful leakage control to preserve retained data. Because the supplied excerpts do not publish a complete verified pinout, timing accuracy, oscillator trim range, or all lifecycle and environmental limits, engineers should confirm those details in the manufacturer datasheet before release. This page combines verified manufacturer and distributor information, price and sourcing details as of 2026-10-29, same-package alternative assessment, and application-focused design guidance. It also separates documented facts from unverified parameters so that procurement and engineering decisions can be made without treating unsupported specifications as guaranteed.
DS1338U-18+T&R - 56-Byte I2C RTC | Analog Devices
The Analog Devices DS1338U-18+T&R is a low-power serial real-time clock with a full binary-coded decimal clock/calendar and 56 bytes of nonvolatile SRAM in an 8-pin uSOP package. The device maintains seconds, minutes, hours, day, date, month, and year information while supporting both 12-hour and 24-hour time formats. Its I2C interface transfers address and serial data through a two-wire connection, making the RTC suitable for compact embedded systems that require accurate timekeeping and persistent data storage. A real-time clock is a clock-and-timing IC that continues tracking calendar time independently of a host processor. Within the semiconductor hierarchy, it belongs to the clock and timing family, while its serial interface and nonvolatile storage place it within the broader category of real-time clock and calendar devices. Unlike a basic digital counter, this RTC records date information and automatically adjusts the end-of-month date for months containing fewer than 31 days. The DS1338U combines an RTC calendar function with 56 bytes of NV SRAM in one package. That SRAM provides persistent space for configuration data, counters, fault flags, or other small records that an embedded controller can access through the same two-wire bus. The integrated arrangement reduces the component count and board area required for a system that needs both timekeeping and a small nonvolatile data store. Communication occurs through an I2C serial interface using two wires for address and data transfer. This interface is suitable for embedded controllers that need to read the current time, configure clock registers, or access the NV SRAM without dedicating multiple parallel pins. The device is identified in the supplied distributor records as an industrial-temperature-grade component in an 8-terminal gull-wing package. Typical uses include industrial embedded controllers, data-acquisition equipment, connected instrumentation, access-control terminals, utility metering, and compact consumer appliances. In each case, the RTC supplies calendar data while the NV SRAM can retain operating state between resets. The two-wire interface also helps preserve connector pins and PCB routing resources in space-constrained designs. Designers should treat the backup supply, oscillator accuracy, operating voltage, and electrical limits as parameters that require confirmation from the manufacturer datasheet. The supplied verified records do not provide those numeric values, so this page does not infer them. PCB planning should also verify the exact uSOP footprint and pin assignment before release, because the distributor listing refers to an 8-pin uSOP form rather than reproducing the complete pinout. This page consolidates verified distributor identification, the official Analog Devices product description, cross-reference findings, practical integration guidance, and a structured comparison of supported same-family alternatives. It is intended to accelerate component identification while clearly separating confirmed information from values that still require datasheet verification.
DS1338U-3+ - Low-Power I2C RTC with 56B NV RAM | Analog Devices
The Analog Devices DS1338U-3+ is a low-power serial real-time clock with a full binary-coded decimal clock/calendar and 56 bytes of nonvolatile SRAM, available in an 8-pin µMAX/TSSOP-style package. It supports an I2C serial interface for address and data transfer. The device provides calendar fields including seconds, minutes, hours, day, date, month, and year, with automatic end-of-month adjustment for months having fewer than 31 days. A real-time clock is a clock-and-timing IC that maintains time independently of the system processor and can preserve calendar or configuration data across power interruptions. The DS1338U-3+ combines an RTC timebase with 56 bytes of NV SRAM, making it useful for embedded systems that need both timestamping and small quantities of retained data. Its low-power design suits battery-backed equipment where continued timekeeping is required while the main supply is absent. The verified manufacturer description identifies the DS1338 series as a full BCD clock/calendar with serial I2C access. The clock/calendar information includes seconds, minutes, hours, day, date, month, and year, while the end-of-month date is automatically adjusted for shorter months. The -3+ ordering suffix is associated with the 2.7 V device variant in the distributor data; exact electrical limits not present in the supplied source snippets are marked as data needed rather than inferred. Typical uses include industrial controllers, data loggers, meters, embedded instruments, and battery-powered systems that require an independent time reference. The I2C interface allows the host processor to read or write clock registers and access the NV SRAM without dedicating multiple parallel pins. Designers should preserve the device-specific pinout and verify voltage, current, oscillator, accuracy, and retention specifications against the manufacturer datasheet before releasing a production design. A key design consideration is matching the RTC supply architecture to the system power source. If the device is intended to maintain time during a main-power interruption, the backup supply and current-consumption requirements must be designed together with the load switch and battery path. The host firmware should also account for I2C address configuration and calendar rollover behavior. This page combines verified distributor and manufacturer information, structured specifications, application guidance, design notes, and only the drop-in alternatives supported by the supplied cross-reference data. It is intended to help engineers evaluate the DS1338U-3+ for embedded timing and nonvolatile data-retention designs while avoiding unsupported assumptions.
DS1338U-3+T&R - 3.3V I2C RTC with 56B NV SRAM | Maxim
Analog Devices / Maxim Integrated DS1338U-3+T&R is a 3.3 V serial real-time clock with 56-byte nonvolatile SRAM, a full binary-coded decimal clock and calendar, and an I2C interface in an 8-TSSOP package. The DS1338U family maintains seconds, minutes, hours, day, date, month, and year information while automatically adjusting the end-of-month date for months with fewer than 31 days. Its combination of real-time clock and nonvolatile memory supports systems that require persistent configuration or event data alongside accurate calendar time. A real-time clock is a semiconductor timer that continues tracking time independently of the system processor. The DS1338U belongs to the RTC and clock/calendar hierarchy, where the clock oscillator and calendar logic preserve time while the host controller reads and writes registers through a serial bus. Its I2C interface reduces the number of signal connections needed compared with a parallel real-time clock, making it suitable for compact embedded systems, industrial controllers, and data-acquisition equipment. The verified device information identifies an 8-pin package with gull-wing leads, an I2C two-wire serial interface, 56 bytes of NV RAM, and a 2.7 V to 3.3 V supply range. The DS1338U-3+T&R ordering code denotes the 3.3 V version supplied in tape-and-reel packaging. The manufacturer describes the device as low power and provides full BCD clock/calendar information. Additional operating limits, oscillator accuracy, current consumption, and electrical timing values are not included in the supplied verified records and therefore remain marked as data needed rather than being estimated. The DS1338 architecture separates timekeeping from the host processor, allowing the controller to retrieve calendar data without maintaining a software time counter. The 56-byte NV RAM can retain a limited amount of configuration or operational information across power cycles. Because the device uses I2C, its bus pull-up requirements, address configuration, operating voltage, and backup-power behavior must be checked against the complete manufacturer datasheet before layout signoff or firmware deployment. Typical uses include industrial automation controllers, embedded instrumentation, metering equipment, communications systems, and compact control boards that need date and time records. In a metering application, the RTC can establish event timestamps while NV RAM stores configuration fragments. In industrial control, it can preserve a time reference independently of the main controller. In communications equipment, the calendar can support event logging and protocol timestamping when the host does not maintain reliable wall-clock time. The primary design consideration is to verify the complete electrical and pinout data before PCB release. The supplied records identify the package and interface but do not provide a verified pin-by-pin description, oscillator load-capacitor recommendations, or backup-supply requirements. Designers should therefore confirm those details in the current Analog Devices DS1338 or DS1338U datasheet rather than infer them from the distributor summaries. This page consolidates the verified manufacturer description, distributor package and supply information, and drop-in comparison evidence for the DS1338U family. It also distinguishes directly verified attributes from unavailable parameters, helping engineers identify the correct voltage variant and determine whether a same-package family member can replace the target without unnecessary redesign.
DS1338U-33+ - I²C RTC with 56B NV RAM | Analog Devices
Analog Devices DS1338U-33+ is a low-power serial real-time clock and calendar with 56 bytes of nonvolatile SRAM, a 3 V to 5.5 V supply range, and an I²C interface in an 8-pin TSSOP or MSOP package. The -33 suffix identifies the device configuration, while the integrated BCD clock/calendar tracks seconds, minutes, hours, day, date, month, and year. A real-time clock is an integrated circuit that maintains time independently of a system processor. The RTC category sits within clock and timing ICs and broader semiconductor timing systems. Unlike a software timer, the DS1338U-33+ can preserve calendar time when the main supply is removed and the device is connected to a backup source, making it useful for systems requiring time stamps, event logging, or scheduling after power restoration. The DS1338U-33+ combines a full BCD clock/calendar with 56 bytes of NV SRAM in one package. Its serial address and data path uses the I²C interface, reducing the number of microcontroller connections compared with a parallel calendar device. The manufacturer describes automatic month-end adjustment for months containing fewer than 31 days, which reduces firmware work when validating date rollover behavior. The integrated SRAM gives the host controller space for small quantities of persistent data without adding a separate memory IC. Applications can store configuration bytes, counters, alarms, or system state alongside the calendar. Because the available source data does not state the exact endurance, retention time, current consumption, oscillator accuracy, or I²C address, those values should be confirmed in the manufacturer datasheet before final qualification. Typical uses include industrial controllers, data loggers, metering equipment, embedded instruments, and access-control or security systems that need a persistent timestamp. The I²C interface is particularly convenient for microcontrollers and system processors that already use a two-wire bus. Designers should account for I²C pull-up resistors, address selection, backup-source isolation, and startup behavior when the main supply returns. The principal design consideration is preserving the correct time across power loss. Follow the manufacturer backup-battery guidance, use the specified decoupling and pull-up networks, and avoid loading the backup source when the main supply is active. Verify the exact package variant and pin mapping against the ordering code because the supplied distributor records reference both 8-TSSOP and 8-MSOP forms. This product record combines current distributor availability, manufacturer functional details, package information, and verified cross-reference results. It also distinguishes documented drop-in candidates from merely similar RTC devices, helping engineers avoid assuming that equivalent timekeeping functions guarantee identical pin compatibility, memory capacity, or package geometry.
DS1338U-33/T&R - 56B I2C RTC | Analog Devices
The Analog Devices DS1338U-33/T&R is a low-power serial real-time clock with a BCD clock/calendar, 56 bytes of nonvolatile SRAM, and an I2C interface, supplied in an 8-pin uSOP package. Its operating supply range is 3 V to 5.5 V, its temperature range is -40°C to +85°C, and the DS1338U-33 suffix identifies the 3.3 V configuration. The device maintains calendar information including seconds, minutes, hours, day, date, month, and year while automatically accounting for months with fewer than 31 days. A real-time clock is a clock-and-timing integrated circuit that preserves time independently of a host processor and system clock. In the component hierarchy, an RTC is a timing IC, a clock-and-calendar device, and ultimately a semiconductor designed for timekeeping and data retention. Unlike a microcontroller timer, the DS1338U can continue maintaining calendar time from a backup source when the main system supply is unavailable, subject to the application backup circuit. The principal feature is 56 bytes of battery-backed nonvolatile SRAM alongside the calendar registers. Address and data move serially through the two-wire I2C interface, allowing a host microcontroller to read or update time and retain small quantities of configuration or operational data. The device includes automatic end-of-month correction, as stated on the Analog Devices product page, reducing host software complexity. A square-wave output provides a periodic reference that can support system timing, alarms, or periodic interrupts when the host schedules an interrupt. The DS1338U is designed for low-power embedded systems that require accurate wall-clock time and a small amount of persistent storage. Its I2C interface reduces the number of connections compared with a parallel RTC, making it suitable for compact controller boards. The -33 configuration is useful where a 3.3 V system is prominent, while the documented 3 V to 5.5 V supply range provides flexibility across industrial and embedded equipment operating from compatible rails. Exact oscillator accuracy and current-consumption figures are not present in the supplied source data and therefore require confirmation in the manufacturer datasheet. Typical uses include industrial controllers, embedded instruments, data-acquisition systems, access-control terminals, and compact communications equipment. Its calendar and persistent-memory functions can record operating events without repeatedly writing nonvolatile data to flash. In designs where wall-clock continuity matters, the backup-supply architecture should be implemented and tested independently of the main 3.3 V rail rather than assuming that a backup capacitor alone meets every retention requirement. PCB design should preserve the I2C signal integrity by keeping SDA and SCL routing short, using continuous ground references, and avoiding long stubs between the DS1338U and its host. Place required input and backup capacitors close to their associated pins. Verify the oscillator crystal or resonator connection against the manufacturer reference layout, because incorrect loading or excessive trace length can affect time accuracy. The uSOP-8 footprint is compact, but exposed-pad-free implementations still require adequate copper for stable electrical and thermal behavior. This page combines the verified manufacturer description, distributor package and ordering information, documented supply and temperature limits, and cross-reference results for the DS1338 family. It also distinguishes true pin-compatible candidates from parts with different packages or added functions, providing practical guidance for RTC selection, replacement, sourcing, and circuit integration.
DS1338Z-18+T&R - I2C RTC with 56B NV SRAM | Analog Devices
The Analog Devices DS1338Z-18+T&R is a low-power serial real-time clock with a full binary-coded decimal clock/calendar and 56 bytes of nonvolatile SRAM, housed in an 8-pin narrow SOIC package measuring 3.90 mm wide. It transfers addresses and data through a two-wire I2C serial interface, providing compact timekeeping and configuration storage for embedded systems. A real-time clock is a clock-and-timing integrated circuit that preserves calendar time independently of the main processor clock. The DS1338 family belongs to the RTC and clock-and-timing hierarchy, where an RTC supplies seconds, minutes, hours, day, date, month, and year information. Its integrated nonvolatile memory allows a host controller to retain operating parameters without adding a separate memory component. The principal features visible in the manufacturer documentation include full BCD clock and calendar data, automatic adjustment for months with fewer than 31 days, serial address and data transfer, and 56 bytes of NV SRAM. The I2C interface reduces the number of signal lines required when compared with a parallel RTC, while the narrow SOIC-8 package supports conventional surface-mount PCB assembly. The DS1338 separates calendar management from the host processor by maintaining time whenever the system is powered by an appropriate backup supply. Calendar fields include seconds, minutes, hours, day, date, month, and year. The automatic month-end adjustment reduces firmware complexity because the device accounts for variable month lengths rather than requiring the controller to implement every calendar correction itself. Typical uses include industrial controllers, data loggers, metering equipment, embedded instrumentation, battery-backed appliances, and connected products that need timestamps. The 56-byte NV SRAM can retain configuration, counters, calibration values, or diagnostic history, subject to the device's operating and retention limits documented by the manufacturer. Designers should place the I2C pull-up resistors and backup-capacitor network according to the manufacturer datasheet, maintain the required logic levels and timing, and avoid assuming that the DS1338's NV SRAM has unlimited endurance. Firmware should detect and recover from invalid BCD or oscillator-start conditions where reliability is important. This product page combines the verified manufacturer description with distributor packaging, inventory, and pricing data, plus practical guidance covering I2C implementation, backup behavior, calendar handling, and component selection. It is intended to help engineers find the correct 8-SOIC ordering code and distinguish the RTC's digital functionality from its electrical operating limits.
DS1338Z-3+ I²C RTC with 56-Byte NV RAM | Maxim Integrated
The Maxim Integrated DS1338Z-3+ is a low-power I²C real-time clock and calendar with 56 bytes of nonvolatile SRAM, a 2.7 V to 5.5 V supply range, and an 8-pin SOIC package. It stores seconds, minutes, hours, day, date, month, and year in full binary-coded decimal format and transfers address and data through a two-wire serial interface. A real-time clock is a timekeeping integrated circuit that maintains calendar information independently of the system processor. The DS1338Z belongs to the RTC and clock/calendar hierarchy within time and memory management semiconductors. Its integrated NV SRAM gives an embedded system a small amount of persistent storage alongside the calendar, which is useful for counters, configuration records, alarms, or small state variables. The DS1338Z automatically accommodates months with fewer than 31 days, according to the Analog Devices product description. The verified manufacturer pages identify the device as a full BCD clock/calendar with 56 bytes of NV SRAM. The -3 suffix distinguishes this orderable variant, while the Z package suffix corresponds to the 8-pin SOIC format shown in distributor listings. These facts are directly relevant when firmware relies on BCD-formatted registers or on persistent data surviving a reset and power cycle. The I²C interface allows the host controller to read and write the clock, calendar, alarms, and SRAM registers serially. This reduces wiring compared with a parallel RTC and supports compact embedded systems. The verified distributor data identifies the component as an 8-SOIC device measuring 3.90 mm wide. Designers should follow the manufacturer datasheet for register addresses, electrical limits, timing, oscillator behavior, and pin assignments rather than infer them from the package outline. Typical uses include industrial controllers, embedded instruments, data-acquisition equipment, access-control terminals, and compact embedded systems that need calendar timestamping with a small persistent memory area. In firmware, the RTC can maintain wall-clock time while the host sleeps, and the NV RAM can retain a limited amount of operating state. The -40°C to +85°C range and 2.7 V to 5.5 V supply range reported by LCSC make the part broadly compatible with embedded industrial and commercial environments. The principal design consideration is verifying software compatibility with the exact BCD register map and I²C address behavior. Firmware must distinguish BCD time values from binary values, handle month-end rollover, and preserve intended SRAM contents across intentional resets and power loss. This page combines verified manufacturer and distributor information, pricing context as of 2026-10-23, package details, application guidance, and explicitly separated drop-in alternatives. This product data is organized for engineers who need a verifiable DS1338Z-3+ purchasing reference. It distinguishes confirmed specifications from information that requires the manufacturer datasheet, avoids unsupported performance claims, and provides practical integration context for I²C real-time clock and nonvolatile memory designs.
DS1338Z-3+T&R - I2C RTC with 56B NV RAM | Analog Devices
Analog Devices DS1338Z-3+T&R is a low-power serial real-time clock and clock/calendar with 56 bytes of nonvolatile RAM, a 2.7 V to 5.5 V supply range, and an 8-pin SOIC package. The integrated RTC records seconds, minutes, hours, day, date, month, and year while automatically adjusting month-end dates for months with fewer than 31 days. Address and data transfer through a two-wire I2C interface, making the device suitable for compact embedded systems that require persistent timekeeping and a small amount of nonvolatile data storage. A real-time clock is a timing IC that maintains calendar information independently of the host processor's main clock. The DS1338 belongs to the RTC and clock/calendar hierarchy within clock and timing integrated circuits. By separating continuous timekeeping from the central processing unit, it reduces firmware overhead and allows the system time to remain available across resets, power interruptions, and low-power operating states when supported by the associated backup supply arrangement. Key features include a full binary-coded decimal clock/calendar, automatic month-end correction, 56 bytes of nonvolatile RAM, serial two-wire communication, and an operating temperature range of -40 C to +85 C. The 2.7 V to 5.5 V operating range supports both 3.3 V and 5 V system rails. Its SOIC-8 package provides a conventional surface-mount footprint compatible with automated assembly and compact mixed-signal or embedded-control boards. The RTC architecture separates calendar processing from the external host while the I2C interface exposes registers and RAM to the processor. Firmware can read the current time, configure clock settings, and use the 56-byte RAM for small amounts of retained configuration or diagnostic information. Because the communication bus is shared, address integrity, pull-up implementation, and software access timing are important considerations when the device shares an I2C segment with sensors, memory, or interface expanders. Typical uses include industrial data loggers, building automation controllers, medical monitoring equipment, security systems, industrial sensors, and compact communication equipment. In each case, the device can maintain wall-clock time while the main controller sleeps or restarts. The integrated RAM also allows small system-specific values to survive a reset without adding a separate memory component. The principal design consideration is preserving an accurate reference during supply interruptions. The DS1338Z-3+T&R is specified for 2.7 V to 5.5 V operation and includes NV RAM, but the supplied product information does not state the backup-battery configuration, oscillator accuracy, or capacitor values. Those parameters must therefore be confirmed in the manufacturer datasheet before finalizing a timekeeping circuit. This product record combines verified manufacturer and distributor information with package, interface, comparison, and design guidance. It identifies where the DS1338Z-3+T&R fits within embedded timekeeping designs, documents the verified 56-byte RAM and I2C characteristics, and distinguishes supported drop-in alternatives without introducing unverified electrical claims.
DS1338Z-33+ - I2C RTC with 56-Byte NV RAM | Analog Devices
The Analog Devices DS1338Z-33+ is a low-power serial real-time clock and calendar with 56 bytes of nonvolatile SRAM, a 3 V to 5.5 V supply range, and an 8-pin SOIC package. It stores calendar and time information in full binary-coded decimal (BCD) format and transfers addresses and data through a two-wire I²C interface. A real-time clock is a clock-and-calendar IC that maintains time independently of a host processor. In the hierarchy of electronic components, the DS1338 belongs to the real-time clock category, then timing ICs, then integrated circuits and semiconductors. Its combination of BCD calendar registers, I²C connectivity, and battery-backed nonvolatile memory makes it useful in embedded systems that require readable time information and persistent configuration storage. Key verified features include seconds, minutes, hours, day, date, month, and year information; automatic month-end adjustment for months with fewer than 31 days; 56 bytes of NV SRAM; and operation from 3 V to 5.5 V. The device is supplied in an 8-SOIC package with a 3.90 mm width. The supplied distributor result identifies the part as a clock/calendar IC with a two-wire serial interface and 56-byte NV RAM. The BCD register organization simplifies direct connection with embedded host software and allows calendar fields to be read over I²C without binary-to-decimal conversion in every register representation. The NV SRAM can retain board-specific data such as configuration values, counters, calibration information, or serialized identifiers when the system is operating from its backup supply. Typical uses include industrial control equipment, data loggers, embedded instruments, access-control terminals, connected sensors, and consumer products requiring a persistent timestamp. The I²C interface allows the RTC to share a two-wire bus with compatible devices, reducing the number of host-controller pins required for timekeeping and small nonvolatile storage. When laying out a design, confirm the SOIC footprint, battery-backup arrangement, I²C address configuration, and decoupling requirements against the manufacturer datasheet. This page distinguishes verified facts from parameters not supplied in the retrieved data and avoids inferring missing electrical or timing values.
DS1338Z-33+T&R - I2C RTC with 56B NV SRAM | ADI
The Analog Devices DS1338Z-33+T&R is a low-power serial real-time clock (RTC) with a full binary-coded decimal (BCD) clock/calendar and 56 bytes of nonvolatile SRAM. It uses a two-wire I2C interface for serial address and data transfer and is supplied in an 8-pin SOIC package. The clock/calendar maintains seconds, minutes, hours, day, date, month, and year information. A real-time clock is an integrated timing device that maintains calendar information independently of a system’s main processor. The RTC category belongs to the broader timing and clock hierarchy and supports timekeeping in embedded systems. The DS1338 combines that calendar function with 56 bytes of nonvolatile SRAM, allowing a controller to retain small amounts of configuration, diagnostic, or application data alongside the time and date. The key feature of the DS1338 family is its compact integration. One 8-pin SOIC device provides an I2C-connected BCD clock/calendar and nonvolatile memory. The manufacturer describes automatic end-of-month adjustment for months with fewer than 31 days, reducing date-management burden in firmware. The verified distributor listing identifies the target as an 8-SOIC real-time clock with 56 bytes of I2C-accessible nonvolatile SRAM. The DS1338Z-33+ device family supports a 3 V to 5.5 V operating range, as reported in the verified component search data. Its serial architecture reduces the number of communication lines required from a microcontroller or other embedded controller. Because address and data share the same two-wire bus, software must distinguish register addresses from register data using the device’s documented I2C protocol and acknowledge behavior. Typical uses include industrial embedded controllers, data-acquisition equipment, communication systems, access-control hardware, and compact consumer products that require persistent timestamps. In these systems, the RTC can retain time across power interruptions while the host controller records events, schedules operations, or timestamps stored measurements. The 56-byte nonvolatile SRAM is useful when a small amount of state must survive a reset or power cycle. Designers should provide the clock circuit and power structure exactly as specified by the manufacturer datasheet, including required crystal or oscillator components and the applicable VCC and VBAT arrangements. Software should also confirm the correct 3.3 V-related device variant and validate BCD-to-decimal conversion, rollover behavior, and I2C address handling during commissioning. This page consolidates verified manufacturer and distributor information for the DS1338Z-33+T&R, adds practical application and design guidance, and identifies drop-in alternatives from the supplied cross-reference search results. It is intended to support component selection without treating unreported electrical details as guaranteed specifications.
DS1501WEN+ - Y2K-Compliant Watchdog RTC, 256B NV SRAM | Maxim
The Maxim Integrated (now Analog Devices) DS1501WEN+ is a full-function, Y2K-compliant real-time clock/calendar (RTC) with RTC alarm, watchdog timer, power-on reset, battery monitors, 256 bytes of NV SRAM, and a 32.768 kHz output, housed in a 28-pin TSSOP (0.465 inch / 11.80 mm width) package. It operates from 3.0 V to 3.6 V supply (typical 3.3 V) with an extended operating temperature range of -40 C to +85 C, and exposes a parallel address/data bus interface. What is an RTC? A Real-Time Clock (RTC) is a dedicated timekeeping integrated circuit that maintains accurate wall-clock time (seconds, minutes, hours, day, date, month, year, century) even when the host system is powered down, typically by backup battery or supercapacitor. RTCs belong to the broader family of clock/calendar ICs, which sit under the timing & application category and ultimately under the power management / system supervision domain. RTCs differ from MCU-internal timers in that they run independently of the host CPU and continue counting through power loss. Key features of the DS1501WEN+ include Y2K-compliant century register, integrated watchdog timer for host firmware supervision, power-on reset and battery monitor circuits, 256 bytes of non-volatile SRAM that retains data through battery backup, and a buffered 32.768 kHz output for downstream clock distribution. The parallel bus allows byte-wide register access for fast data reads/writes. Internally, the DS1501 uses a low-power CMOS oscillator driving a chain of BCD-coded registers (century, year, month, date, day, hours, minutes, seconds). The on-chip NV SRAM is automatically switched to backup battery when VCC falls below a programmable threshold, and the device asserts RST on power-up to safely initialize the host CPU. The watchdog can be programmed to reset the host if a strobe is not received within a defined window. Typical applications include embedded industrial controllers requiring time-stamped event logging, point-of-sale (POS) terminals, secure access controllers, medical instruments with battery-backed timekeeping, and server/workstation BIOS clock replacement. The wide temperature range and integrated supervisory functions make it suitable for harsh environments. When designing with this device, ensure VBAT is connected to a backup lithium coin cell or supercapacitor through the recommended decoupling network; verify that the host's parallel bus timing matches the DS1501 access specifications. The XAIPART datasheet documents detailed read/write timing diagrams and battery switchover thresholds. This product page synthesizes distributor pricing, drop-in alternatives, and practical design notes that go beyond the manufacturer datasheet.
DS31408GN+ - 8-Input 14-Output Dual DPLL Timing IC | Microchip
The Microchip DS31408GN+ is a flexible, high-performance timing IC for frequency conversion and frequency synthesis in telecom and networking equipment, housed in a 256-pin CSBGA package (17x17 mm). It features 8 input clocks and 14 output clocks, each capable of accepting or generating nearly any frequency between 2 kHz and 750 MHz, with sub-ps output jitter and integrated 1588 clock support. A DPLL (Digital Phase-Locked Loop) timing IC is a high-precision frequency synthesis and jitter-cleaning device used in telecom, Ethernet, and synchronization networks. Within the system hierarchy, a DPLL belongs to the timing IC family, which sits under clock generation, clock distribution, and clock & timing integrated circuits - a critical category in power management and signal chain design where reference clocks, PTP (Precision Time Protocol), and Stratum-compliant timing are required for carrier-grade equipment. Key features of the DS31408GN+ include: a dual DPLL architecture with independent holdover and reference switching, support for Ethernet, SONET/SDH, Stratum 2/3E, and telecom line rates, sub-picosecond output jitter performance, integrated IEEE 1588 hardware support for PTP timestamping, and CMOS/TTL compatible I/O. The device includes on-chip EEPROM for autonomous configuration and supports SPI/I2C host interfaces for in-system programmability. The DS31408GN+ integrates two independent DPLLs, each capable of locking to any of the 8 input references, with programmable bandwidth and fast-lock algorithms that minimize wander during reference switching. Its fractional-N output dividers support virtually any output frequency between 2 kHz and 750 MHz, eliminating the need for multiple discrete timing ICs in multi-protocol line cards. Typical applications include SONET/SDH line cards, Ethernet switches and routers requiring SyncE or PTP synchronization, OTN (Optical Transport Network) equipment, base station synchronization, and Stratum-compliant timing subsystems in carrier-grade infrastructure. The dual-DPLL architecture is particularly valuable in equipment that must hold frequency during a primary reference failure. When designing with this device, provide a low-jitter crystal or TCXO reference at the primary input and observe PCB layout guidelines for mixed-signal clock circuits - keep output traces impedance-controlled and length-matched, and decouple each supply pin with 0.1 uF ceramic capacitors placed as close as possible to the BGA balls. The 256-pin BGA package requires careful fanout and via-in-pad PCB technology for reliable assembly. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, helping timing engineers select the right configuration of the DS31408 platform for their application.
DS3231M+ - ±5 ppm I2C Real-Time Clock | Maxim Integrated
The Maxim Integrated DS3231M+ is a ±5 ppm I2C real-time clock (RTC) with clock and calendar functions, available in a 16-pin SOIC package. It combines a MEMS resonator with a temperature-compensated timekeeping engine, supports a 2.3 V to 5.5 V operating supply range, and maintains timekeeping from a coin-cell battery when the main supply is removed. The DS3231M+ provides a low-cost, highly accurate timebase for embedded systems that need seconds, minutes, hours, calendar date, and alarm functions over an I2C bus. A real-time clock is a clock-and-timing IC that preserves calendar time independently of a system processor. The RTC category sits within integrated timing circuits, where an oscillator and digital timekeeping logic maintain a reference even when the main system is unpowered. The DS3231M+ uses a MEMS resonator rather than a conventional quartz crystal, reducing external components while supporting stable long-term timekeeping. Its integrated temperature compensation is designed to maintain accuracy across changing ambient conditions. The device supports a 400 kHz I2C interface, two programmable alarms, and a square-wave output that can be used for periodic interrupts or clocking-related functions. Register access and real-time data use the familiar BCD date and time format. The DS3231M+ is specified for a 16-pin, 7.50 mm-wide SOIC package, making it suitable for compact embedded boards that use a common 16-pin land pattern. Its internal MEMS resonator eliminates the need for an external crystal, while the integrated digital compensation removes external calibration components. The result is a compact timebase with fewer external components than a discrete crystal-and-capacitor implementation. The device can operate directly from a 3.3 V or 5 V system supply while preserving the calendar through a backup battery. Typical uses include industrial data loggers, environmental monitors, instrumentation, embedded control systems, network appliances, and consumer electronics. It is especially useful when the host microcontroller can be reset or power-cycled but the system must retain wall-clock time. Its I2C interface also allows firmware to obtain time without burdening the host with timing logic. Designers should use suitable pull-up resistors on the I2C bus, connect the backup battery to the designated supply input, and review the oscillator-startup and power-loss behavior in the manufacturer datasheet. PCB placement should keep I2C routing away from high-current switching nodes and noisy sources. For timing-critical systems, validate the complete power, layout, and firmware configuration rather than relying only on nominal RTC accuracy.
DS3231M+TRL - ±5ppm I2C RTC in 16-SOIC | Analog Devices
The Analog Devices DS3231M+TRL is a low-cost, extremely accurate I2C real-time clock with ±5 ppm accuracy, a 2.3 V to 5.5 V operating range, and a 16-SOIC package. It integrates a MEMS resonator and a battery backup input, allowing accurate timekeeping to continue when the main supply is interrupted. The device registers calendar and clock data over the two-wire I2C interface and includes alarm-capable RTC functionality identified in the verified component data. A real-time clock is a timekeeping integrated circuit that preserves date and time information independently of a system's main processor. The DS3231M belongs to the RTC, clock-and-calendar, timekeeping IC, and power-management semiconductor hierarchy. Unlike a simple oscillator, an RTC maintains structured calendar information and typically includes an I2C host interface so embedded software can read or set the current time. The DS3231M+TRL's headline advantage is its specified ±5 ppm frequency accuracy. The integrated MEMS resonator replaces a discrete quartz crystal while reducing assembly component count. Its 2.3 V to 5.5 V supply range permits operation in both 3.3 V and 5 V systems. A dedicated battery input preserves timekeeping during main-power loss, and the I2C interface connects directly to a host microcontroller or other embedded controller. The 16-SOIC package is specified as WSOIC-16 by one distributor listing, with a listed body width of 7.50 mm. The verified component description identifies the device as an alarm RTC using day, date, month, year, hour, minute, and second date-time formatting. These characteristics make it appropriate for systems where time must remain traceable across power cycles without relying entirely on a network time service. Typical applications include industrial controllers, data-acquisition equipment, embedded instruments, access-control terminals, and compact sensor nodes. In each case, the RTC supplies a local time reference while the system processor performs measurement, control, logging, or communication. Its I2C interface avoids the use of many discrete I/O lines and is especially useful in designs where board area and component count are constrained. Designers should treat the battery path as a power-reliability feature rather than a substitute for a fully specified primary supply. I2C pull-up resistors, bus speed, and address selection must be checked against the host system. Because the exact exposed-pad and pin-level details were not included in the supplied verified data, engineers should confirm the complete land pattern and pin assignment against the manufacturer datasheet before layout release. This page consolidates verified manufacturer and distributor information, supply references, comparison parameters, and practical selection guidance for engineers evaluating the DS3231M+TRL. It also distinguishes directly comparable same-family parts from alternatives that require different packages or functional verification, avoiding unsupported drop-in claims.
DS3231MZ+ - ±5ppm I2C RTC with TCXO | Maxim Integrated
The Maxim Integrated DS3231MZ+ is an extremely accurate I2C real-time clock (RTC) with an integrated temperature-compensated MEMS resonator, providing ±5 ppm accuracy over 0°C to +50°C in an 8-pin SOIC (0.154", 3.90 mm width) package. It operates from a 2.3 V to 5.5 V supply and maintains timekeeping through an external backup battery when main power is interrupted. Communication is via a fast 400 kHz I2C (2-wire) serial interface with time/date registers in HH:MM:SS and YY-MM-DD-dd format. Source: Maxim/Analog Devices DS3231M datasheet. A real-time clock (RTC) is a dedicated low-power timing IC that keeps wall-clock time (seconds, minutes, hours, day, date, month, year) independently of the main MCU. It sits in the system hierarchy alongside power management and supervision ICs, between the backup battery and the host processor. Unlike an MCU's internal timer, an RTC continues counting during main power loss, making it the canonical block for data-logger timestamping, scheduled wake-ups, and any application that must remember "when" across power cycles. The DS3231M family specifically replaces a discrete crystal + TCXO with an on-chip MEMS resonator, eliminating PCB crystal layout and trimming steps. Key features include ±5 ppm accuracy (±2.17 minutes/year) without user calibration, integrated MEMS resonator that removes external crystal requirements, automatic backup switching to a battery on VCC loss, two programmable time-of-day alarms, a square-wave output (1 Hz, 1.024 kHz, 4.096 kHz, 8.192 kHz), and an I2C bus rated to 400 kHz fast mode. The 8-SOIC package is pin-compatible with the popular DS1307 footprint family and other 8-pin RTCs. Operating temperature spans the industrial -40°C to +85°C range, and the part consumes roughly 110 µA active and 3 µA in timekeeping mode with VCC removed. The DS3231M uses a silicon MEMS resonator trimmed at the factory, eliminating the need for external load capacitors or PCB crystal layout. An on-chip temperature sensor drives a compensation circuit that adjusts the counter, achieving the ±5 ppm rating without user intervention. Battery-backup mode is transparent to the user: when VCC drops below the battery voltage, an internal switch redirects the supply to the backup source and the oscillator keeps running. Per the manufacturer datasheet, the BB32 pin accepts a 3 V lithium cell (CR2032 typical) and the device draws 3 µA from the battery in timekeeping mode. Typical applications include Arduino/Raspberry Pi data-logger timestamps, IoT sensor nodes that wake on RTC alarm, point-of-sale terminals requiring accurate transaction time, GPS-disciplined wall-clock backup, and industrial controllers with scheduled logging. The 8-SOIC footprint drops onto thousands of existing DS3231 / DS1307 module PCBs, making it the lowest-effort upgrade from generic crystal RTCs. When designing with the DS3231MZ+, place a 0.1 µF decoupling capacitor as close as possible to VCC and a backup battery on the BB32 pin through a decoupling network; ensure the I2C lines (SCL, SDA) are pulled up to VCC with 4.7 kΩ resistors for reliable 400 kHz operation. The INT/SQW pin can be left open or used as an interrupt source for the host MCU. This page synthesizes distributor pricing, drop-in alternatives in the same 8-SOIC package, and practical design notes that go beyond what is found in the manufacturer datasheet alone.