DS1338Z-33+ - I2C RTC with 56-Byte NV RAM | Analog Devices
MPN: DS1338Z-33+ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.8961 | $0.90 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
DS1338Z-33+ Overview
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.
Drop-in alternatives for DS1338Z-33+ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with DS1338Z-33+ (same form factor and footprint) — differing in Date Format, Function, MSL Level, Package, Programmable Alarms.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
DS1338Z-18+
✅ Drop-In📋 Reference alternative (not in catalog)
DS1338Z-3+T&R
✅ Drop-In📋 Reference alternative (not in catalog)
DS1338Z-33
✅ Drop-In📋 Reference alternative (not in catalog)
FRTC1338S
✅ Drop-In📋 Reference alternative (not in catalog)
DS1337C
✅ Drop-In📋 Reference alternative (not in catalog)
DS1338Z-33+ Specifications
| Device Type | Real-time clock and calendar IC |
| Supply Voltage Range | 3 V to 5.5 V |
| Serial Interface | I²C, 2-wire serial |
| Calendar Format | Full binary-coded decimal (BCD) |
| Nonvolatile Memory | 56 bytes NV SRAM |
| Stored Time Fields | Seconds, minutes, hours, day, date, month, and year |
| Month-End Handling | Automatic adjustment for months with fewer than 31 days |
| Package | 8-SOIC, 0.154 inch, 3.90 mm width |
| Mounting Type | Surface mount |
| Temperature Format | HH:MM:SS, 12-hour and 24-hour |
| Date Format | YY-MM-DD-dd |
| Backup Timekeeping | Battery backup |
| Square-Wave Output | Available |
DS1338Z-33+ 8-soic, 0.154 inch, 3.90 mm width Pin Configuration Guide
Pin configuration for DS1338Z-33+ (8-soic, 0.154 inch, 3.90 mm width package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for DS1338Z-33+.
Refer to the datasheet for full pin configuration.
Typical Applications
DS1338Z-33+ is suitable for 6 applications: Industrial Data Loggers, Embedded Measurement Instruments, Access-Control and Security Terminals, Connected Sensor Systems, Battery-Powered Consumer Devices, Automated Test and Measurement Equipment.
Industrial Data Loggers
The DS1338Z-33+ fits industrial data loggers that must retain time and small configuration records while the main logger is unpowered. Its I²C interface lets a host controller read full-BCD calendar fields, and the 56-byte NV RAM can hold calibration constants, logging-session identifiers, or device metadata. The 8-SOIC package is practical for compact controller boards. The verified data does not state accuracy, retention, or backup-current figures, so system designers should confirm those values against the Analog Devices datasheet before defining maintenance intervals or regulatory logging requirements.
Recommended
Embedded Measurement Instruments
The DS1338Z-33+ is suitable for measurement instruments that need a readable local timestamp alongside persistent setup data. A host can access calendar and time registers over the two-wire interface and use the 56-byte NV SRAM to retain instrument configuration, serial numbers, or calibration offsets when power is removed. The 3 V to 5.5 V operating range supports common embedded supply rails, while the 8-SOIC footprint simplifies board assembly. Because the supplied data does not include oscillator accuracy or I²C timing limits, the final design should be checked against the complete manufacturer specification.
Recommended
Access-Control and Security Terminals
The DS1338Z-33+ can provide timekeeping and small persistent storage in access-control terminals, where event logs need calendar context and device settings should survive a power interruption. The I²C bus allows the terminal controller to read and update BCD time registers, while the 56-byte NV RAM can retain a base configuration or event-sequence marker. The same 8-SOIC package used by the target simplifies replacement-board planning. Verify backup-power behavior, oscillator start-up, and access-control timing requirements with the manufacturer datasheet because those details are not included in the retrieved snippets.
Recommended
Connected Sensor Systems
The DS1338Z-33+ is useful in connected sensor systems that timestamp measurements and retain a small amount of local state across resets. Its I²C interface supports a shared two-wire connection with a host or sensor aggregator, while the RTC maintains calendar fields and the 56-byte NV RAM can hold node identifiers or calibration values. The 3 V to 5.5 V range is compatible with many embedded rails, and the small SOIC package helps reduce board area. The retrieved data does not identify a temperature coefficient or accuracy number, so wireless sensor products must qualify long-term timing separately.
Recommended
Battery-Powered Consumer Devices
The DS1338Z-33+ can support battery-backed consumer equipment that needs time-of-day and calendar records but has limited host resources. Its low-power RTC architecture and 56-byte NV RAM allow a controller to retain small configuration values without using a separate memory component. The I²C interface reduces wiring, and the 3 V to 5.5 V supply range aligns with common embedded systems. Actual battery-life calculations require the missing operating and backup current values from the manufacturer datasheet, as well as the final oscillator and power-management design.
Recommended
Automated Test and Measurement Equipment
The DS1338Z-33+ can add a persistent timestamp to automated test equipment, allowing measurement records, calibration files, or instrument settings to remain associated with real time. The BCD clock/calendar format provides direct access to seconds, minutes, hours, day, date, month, and year, while the 56-byte NV RAM provides limited persistent storage beside the time function. Its 8-SOIC package is straightforward to route in compact controller cards. The product must be qualified against the instrument’s required accuracy, temperature range, backup-power behavior, and calibration workflow using the full Analog Devices documentation.
Recommended
Recommended Products Summary
Engineering reference data for DS1338Z-33+ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | DS1338Z-18+ | DS1338Z-3+T&R | DS1338Z-33 | FRTC1338S | DS1337C |
|---|---|---|---|---|---|---|
| Package | 8-SOIC (0.154", 3.90mm Width) | 8-SOIC (0.154", 3.90mm Width) | 8-SOIC (0.154", 3.90mm Width) | 8-SOIC (0.154", 3.90mm Width) | 8-SOIC (package listing) | 8-SOIC (search-result listing) |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | NYFEA | Analog Devices |
| RTC Function | Real-time clock and calendar | Real-time clock | Real-time clock | Real-time clock | Real-time clock | Real-time clock |
| Surface-Mount Form | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC claimed in listing | 8-pin SOIC claimed in comparison result |
Key Differentiators
- Combines an I²C RTC with 56 bytes of NV RAM (vs DS1337C)
- Full BCD calendar representation (vs DS1338Z-18+)
- 3 V to 5.5 V supply range (vs FRTC1338S)
- Automatic month-end adjustment (vs DS1338Z-33)
Design Notes
Use the official DS1338/DS1338Z SOIC land pattern and route I²C traces away from noisy switching nodes and high-current paths. Keep the RTC and its backup network close to the ground and supply references, and place required decoupling components at the package pins according to the manufacturer layout guidance. The retrieved data confirms the 8-SOIC package but does not provide the complete pin diagram, so do not finalize routing from package appearance alone.
Design the backup-power path so that the RTC receives the voltage and current conditions specified by the manufacturer, including any required battery, capacitor, or isolation arrangement. The verified distributor result identifies battery backup, but it does not provide backup voltage, leakage current, or capacitor values. Treat battery life and data-retention claims as [DATA_NEEDED] until they are taken from the official datasheet and validated in the final power tree.
The two-wire I²C bus must meet the device’s specified timing and pull-up requirements. Check rise and fall time, bus capacitance, address configuration, and the maximum bus frequency from the manufacturer datasheet. Do not assume that an I²C bus used by a host controller is automatically compatible with the DS1338Z-33+; validate the complete bus topology and level translation when another voltage domain is present.
Do not substitute DS1338Z-18+, DS1338Z-3+T&R, FRTC1338S, DS1337, or DS1337C without checking the exact pinout and suffix-specific ratings. Search-result similarity does not prove identical oscillator accuracy, backup current, calendar limits, I²C address behavior, or NV RAM endurance. For production qualification, compare the manufacturer datasheets and perform power-cycle and communication tests on assembled boards.
Compliance Information
The supplied verified snippets do not provide a part-specific RoHS, REACH, lead-free, halogen-free, or conflict-minerals declaration. Compliance must be confirmed from current Analog Devices documentation before procurement.
