Takt & Timing
Produkte (137)
MASC-38040 - 28.9 GBaud 4-Channel PAM-4 CDR | MACOM
MACOM MASC-38040 is a four-channel, reference-free clock and data recovery retimer operating from 25.78 GBaud to 28.9 GBaud in a 5.2 mm x 5.2 mm QFN-compatible package. Its headline specifications are four PAM-4 channels, 28.9 GBaud maximum signaling rate, and single 1.8 V supply operation. Each channel can be controlled through a two-wire I2C-compatible interface, while a bypass mode supports legacy or nonstandard data rates. A clock and data recovery retimer is an IC that recovers a usable clock from a high-speed serial stream, resynchronizes data, and can compensate for accumulated timing and jitter problems. In the optical and digital-communications hierarchy, the MASC-38040 belongs to retiming CDR and clock-and-data recovery devices used in PAM-4 links operating at tens of gigabauds. Key features include reference-free operation across 25.78 to 28.9 GBaud, four independently controllable channels, bypass support, and a single 1.8 V power rail. The two-wire I2C-compatible control path simplifies configuration of multiple lanes. These characteristics suit systems requiring one retiming device to manage several parallel high-speed links rather than using separate single-channel recovery circuits. Technically, the device is positioned for 56G-class PAM-4 receive paths, where source, package, connector, and trace losses can impair timing recovery. Reference-free CDR operation is useful when the transmitter does not provide a separate usable reference. Bypass mode adds deployment flexibility for legacy or nonstandard rates, although the verified source does not specify which rates and modes are supported. Typical uses include 400G and 800G optical receivers, coherent communication modules, high-speed optical DSP test systems, and parallel data links. Each lane can be configured through the common control interface, helping synchronize operating states across a multi-channel receiver. PCB design should preserve short high-speed differential routes, continuous reference planes, and symmetrical via transitions. The 1.8 V rail requires local high-frequency decoupling and adequate return paths. Engineers must consult the manufacturer documentation for exact pin assignments, electrical limits, channel-count interpretation, bypass behavior, and exposed-pad requirements. This page consolidates the verified manufacturer specifications and explicitly identifies missing technical, commercial, pinout, compliance, and replacement data rather than estimating it. It also distinguishes a true pin-compatible replacement from unrelated QFN clock-and-data recovery devices.
MATA-37144 - Selectable-Bandwidth TIA/CDR | MACOM | Optical
The MACOM Technology Solutions MATA-37144 is a four-channel 25G/28G clock and data recovery amplifier with an integrated high-sensitivity transimpedance amplifier, limiting amplifier, and programmable output driver. Its selectable TIA bandwidth supports legacy data rates, while programmable slice level, loss-of-signal threshold, output swing, and de-emphasis provide receiver-chain control. The supplied data does not state the package or its physical dimensions. A clock and data recovery amplifier, or CDR, reconstructs a usable digital data stream and recovered clock from a degraded high-speed optical signal. This MACOM device combines the photodiode-input TIA, decision circuitry, and output-driver functions in one optical receiver path. In the signal-chain hierarchy, it belongs to clock and timing components and interface electronics, rather than a general-purpose digital logic IC. The MATA-37144 is specifically identified as a four-channel 25G/28G CDR with an integrated TIA. Its high-sensitivity TIA includes selectable bandwidth for legacy-rate support. After amplification, the limiting amplifier provides a defined decision function, while programmable output swing and de-emphasis allow downstream circuitry to be matched to channel and board conditions. Programmable slice-level adjustment and LOS-threshold control support receiver calibration and loss-of-signal detection. The verified source also associates the MATA-37144 with an average photodiode-current monitor identified as RSSI. This measurement feature helps a system evaluate received optical power indirectly. Together, the TIA, slicer, LOS control, RSSI monitoring, and programmable driver create a configurable receiver chain rather than a fixed-gain amplifier. Exact gain, sensitivity, bandwidth selections, data rates, supply voltage, power consumption, and channel-to-channel coupling require datasheet verification. The most relevant applications are 25G/28G optical transceiver receivers, legacy-rate-compatible optical links, parallel four-channel architectures, receiver equalization and de-emphasis experiments, and loss-of-signal monitoring systems. For these uses, designers should evaluate channel budget, photodiode capacitance, target line rate, recovery range, output impedance, and PCB channel loss before committing to a receiver implementation. A key design consideration is that programmable bandwidth, slice level, LOS threshold, output swing, and de-emphasis do not replace optical-power budgeting or channel simulation. Set receiver controls through validated firmware, preserve receiver eye margin, and verify compliance with the exact variant datasheet. The available evidence does not identify whether MATA-37144 is a catalog, die, tape-and-reel, or other package configuration. This page separates verified manufacturer-level facts from unavailable parameters and records every missing electrical or package attribute rather than estimating it. It also explains why a same-footprint replacement cannot be recommended until the package and pinout are verified. For an equivalent device, compare data rate, channel count, optical input sensitivity, bandwidth modes, LOS behavior, RSSI implementation, electrical interfaces, supply requirements, and package-level pin compatibility.
MC1648M - Voltage-Controlled Oscillator | Motorola
The Motorola MC1648M is a voltage-controlled oscillator designed for frequency synthesis, modulation, and signal-generation applications. According to the available Motorola MC1648 documentation, the device requires an external parallel tank circuit consisting of an inductor and capacitor; maximum performance is obtained with QL greater than or equal to 100 at the operating frequency. A varactor diode may be placed in the tank circuit to provide a voltage-variable input for voltage-controlled oscillator operation. A voltage-controlled oscillator, or VCO, generates an output signal whose frequency varies with an applied control voltage. The MC1648 belongs to the broader clock and timing IC family, where it provides a tunable oscillator rather than a fixed-frequency clock. Its external tank circuit allows the designer to select inductance and capacitance for the target operating range, while the control voltage provides fine frequency adjustment. This architecture is useful in FM transmitters, frequency synthesizers, clock-generation circuits, and frequency-discriminator systems. The main verified technical characteristics are its external parallel LC-tank requirement and the recommended tank quality factor of QL at least 100 for maximum performance. The device also supports voltage-variable operation when a varactor diode is incorporated into the tank circuit. The supplied search results identify MC1648M as a Motorola voltage-controlled oscillator and associate it with a DIP-style MC1648 package family, but the detailed electrical ratings, frequency limits, supply voltage, output characteristics, pin names, and package dimensions were not included in the verified dataset. For design implementation, the external tank components should be placed close to the oscillator pins and selected for the intended frequency range. Component tolerance, parasitic capacitance, and inductor Q can shift the operating frequency. The control-voltage range and permitted control-voltage slew rate should be verified in the manufacturer datasheet before relying on the part for precision frequency control. Typical uses include FM radio modulation, tone generation, frequency conversion, and tunable clock sources. The MC1648M is most appropriate when an external LC network and application-specific frequency calibration are acceptable. Modern designs may instead choose a higher-integration oscillator when smaller size, digital calibration, or a specified phase-noise performance is required. This page combines the verified Motorola MC1648 tank-circuit requirements, distributor availability information, pricing context, and practical selection guidance. The verified distributor listing shows MC1648M in stock at LCSC with a starting price of $1.0043. Pricing and inventory should be checked with the authorized supplier before purchase, especially because legacy semiconductor availability can vary by package, region, and production status.
MCP79410-I/MS - I2C RTC with EEPROM and Battery Backup | Microchip
The Microchip MCP79410-I/MS is an I2C-compatible real-time clock/calendar with 1 Kbit EEPROM, 64-byte SRAM, unique ID, and automatic battery switchover, supplied in an 8-MSOP package. It operates from 1.8 V to 5.5 V across -40°C to +85°C and uses a 32.768 kHz crystal for timekeeping. The device combines a calendar clock, configurable alarms, nonvolatile storage, and backup-power management in one compact component. A real-time clock, or RTC, is a low-power timing integrated circuit that maintains wall-clock time independently of the system processor. An RTCC extends the basic RTC function with calendar registers for seconds, minutes, hours, dates, months, and years. The MCP79410 belongs to the RTC, RTCC, clock/calendar, and timekeeping IC hierarchy and interfaces to a host through a two-wire I2C-compatible serial interface. The MCP79410 provides 1 Kbit of EEPROM for persistent configuration or event records and 64 bytes of SRAM for temporary data. Its battery-switchover circuit allows the clock and memory to remain operational from a backup source when the primary supply fails. A timestamp mechanism records the power-failure event, while digital timing compensation compensates for crystal error and improves timekeeping accuracy without relying only on fixed analog calibration. According to the manufacturer datasheet, the clock supports automatic month-length handling, leap-year correction, 24-hour or 12-hour formats, programmable alarms, and a configurable CLKOUT. The MCP79410 family also includes a power-sense function that supports automatic transition between the primary supply and backup battery. The -I/MS ordering suffix denotes the specified package and temperature treatment, while /MS identifies the MSOP package used by this MPN. Typical uses include industrial controllers, embedded instruments, data loggers, meters, medical equipment, communication modules, and consumer electronics requiring accurate time stamps. Compared with software timekeeping based on a microcontroller timer, the RTC maintains a dedicated time base across resets, sleep states, and main-power interruptions. Its I2C interface also allows firmware to read and write time and memory data efficiently. The most important design checks are the 32.768 kHz crystal network, I2C pull-up resistors, decoupling capacitors, backup-battery configuration, and VBATEN handling. Firmware must configure the relevant control registers and verify the device address before normal operation. Because clock accuracy depends on the crystal and its load network, PCB placement and grounding should follow the manufacturer's recommended layout guidance. This product page combines verified distributor information, manufacturer technical facts, application guidance, and design considerations. It is intended to help engineers evaluate the MCP79410-I/MS for compact, battery-backed real-time clock and calendar designs, including comparisons, procurement questions, firmware considerations, and practical integration advice.
MCP79510T-I/MS - SPI RTCC 1Kb EE 64B SRAM | Microchip
The Microchip Technology MCP79510T-I/MS is a 10-pin MSOP SPI Real-Time Clock/Calendar (RTCC) with 1 Kbit EEPROM and 64 bytes battery-backed SRAM, designed for low-power timekeeping in embedded systems. Operating from 1.8V to 3.6V across the industrial -40C to +85C range, it integrates a digital-trimmed 32.768 kHz oscillator and battery switchover circuitry for backup power. The MCP79510T-I/MS uses a standard 4-wire SPI serial interface and is offered in a 10-MSOP (3.00 mm) surface-mount package. A Real-Time Clock (RTC) is a dedicated integrated circuit that maintains accurate time and date information independently of the host processor, typically counting seconds, minutes, hours, days, months and years. RTCs sit beneath clock & timing ICs in the broader semiconductor hierarchy: RTC -> clock & timing -> timing IC -> power management/interface IC. Battery-backed RTCs retain time during main power loss, making them essential for any system that must log events with wall-clock timestamps across power cycles. Key features of the MCP79510T-I/MS include digital trimming for improved long-term accuracy, software-controlled block write-protect for the EEPROM, a power-fail timestamp that captures the moment of main power loss, and a 64-byte SRAM that retains user data during backup. The integrated battery switchover automatically routes power from an external backup cell when VCC drops below the threshold, eliminating external MOSFETs and comparator circuits. Its event-detection input and configurable alarm provide a flexible wake-up mechanism for low-duty-cycle battery applications. The MCP79510 family shares a common register map and SPI command set across the MCP79510, MCP79511, MCP79512 and MCP79520/21/22 variants, allowing firmware reuse. The MCP79510T-I/MS is the 1 Kbit EEPROM member with 64 B SRAM, while the MCP79511/12 double the EEPROM and SRAM, and the MCP79520/21/22 add a unique 64-bit EUI-48/EUI-64 MAC ID for network-connected designs. Designers should consult the Microchip MCP79510 product page and the family datasheet (DS22078D) for the precise register differences. Typical applications include industrial data loggers, smart meters, medical monitoring devices, point-of-sale terminals, security alarm panels, and IoT edge nodes. The wide operating voltage and integrated battery switchover make the part drop-in compatible with both regulated 3.3V rails and direct Li-ion battery stacks. For designs that need higher accuracy, the digital trimming register allows sub-ppm adjustment against a known reference such as a GPS-disciplined oscillator. When designing with the MCP79510T-I/MS, place a 1 uF to 10 uF decoupling capacitor close to VCC and route the 32.768 kHz crystal traces symmetrically to minimize load-capacitance mismatch. The backup battery input should be decoupled with a small ceramic cap to absorb inrush during switchover; do not exceed the absolute maximum VCC or BAT voltage or the on-chip battery switchover circuit will be damaged.
MCP79511-I/MS - SPI RTCC, 64B SRAM, 10-MSOP | Microchip
The Microchip Technology MCP79511-I/MS is a 3V SPI Battery-Backed Real-Time Clock/Calendar (RTCC) IC with 64-byte SRAM and pre-programmed EUI-48 MAC ID, housed in a 10-pin MSOP package. The device integrates a digital-trimmed timekeeper, automatic battery switchover, 64-byte battery-backed SRAM, and 2 Kbit EEPROM for non-volatile parameter storage. According to the Microchip product page, the MCP79511 SPI RTCC is highly integrated with memory and advanced features normally found in higher-priced devices. A Real-Time Clock (RTC) IC is a low-power timekeeping device that maintains accurate wall-clock time (seconds, minutes, hours, day, date, month, year) and calendar functions even when the main system is powered down. RTCs typically include a backup power input (battery or supercapacitor) to keep time during outages, and they communicate with a host microcontroller via serial interfaces such as I2C, SPI, or parallel buses. Within the broader hierarchy, an RTCC sits under Clock & Timing ICs -> Integrated Circuits, and shares architectural lineage with calendar/watchdog timers used in metering, data loggers, and secure element designs. Key features of the MCP79511-I/MS include digital trimming for high-accuracy timekeeping (typically ±5 ppm across the industrial temperature range), automatic power-switchover to a backup battery when VCC drops below threshold, two configurable interrupt outputs for alarms and watchdog functions, and a unique pre-programmed 48-bit MAC address (EUI-48) that simplifies networking product compliance. The SPI interface operates at up to 5 MHz for fast register access and supports 1-byte to 64-byte block writes to the SRAM and EEPROM. The integrated 2 Kbit EEPROM provides ample storage for application parameters, configuration data, or tamper logs. Architecturally, the MCP79511 uses a 32.768 kHz crystal oscillator input with an on-chip digital trimming DAC, allowing fine frequency adjustment to compensate for crystal tolerance and aging. The device's power-sense circuitry continuously monitors VCC and seamlessly switches to backup supply without losing time integrity, which is critical for metering, security, and IoT edge nodes. A separate backup-supply pin (VBAT) accepts 1.3V-3.6V, supporting lithium coin cells or supercapacitors. Typical applications include smart energy metering (AMI), data loggers with timestamping, industrial automation controllers requiring scheduling, security alarm panels, IoT edge nodes with secure timekeeping, and any embedded system needing persistent date/time during power cycles. The pre-programmed EUI-48 MAC ID simplifies Wi-Fi, Ethernet, or 6LoWPAN commissioning and avoids the need for external MAC address storage. When designing with the MCP79511-I/MS, place the 32.768 kHz crystal as close to the X1/X2 pins as possible and use load capacitors that match the crystal's specified load capacitance (typically 6-12.5 pF). Decouple VCC and VBAT with 100 nF ceramic capacitors to handle the automatic switchover transient and prevent register corruption. This page synthesizes Microchip datasheet specifications, distributor pricing as of 2026-10-09, verified drop-in alternatives, and practical design notes not typically assembled on a single manufacturer datasheet page.
MCP79511T-I/MS - 3V SPI RTC with EUI-48 | Microchip
The Microchip Technology MCP79511T-I/MS is a 3 V SPI real-time clock/calendar with 64-byte battery-backed SRAM, 1 Kbit EEPROM, and a pre-programmed EUI-48 MAC ID. Its 10-pin MSOP package supports battery switchover, digital trimming, an interrupt output, alarms, events, and a pre-programmed unique identifier. The device targets systems requiring accurate timekeeping, low-power backup, and secure network identity. What is a real-time clock/calendar? An RTC maintains time and calendar information independently of the system processor, typically from a crystal oscillator and backup supply. An SPI RTC combines that timekeeping function with a serial peripheral interface and nonvolatile storage. The MCP79511T-I/MS belongs to the RTC and clock/timing category, providing system time, retained data, and programmable events without relying entirely on a microcontroller. The MCP79511 family combines digital trimming compensation, a backup-power switchover circuit, and pre-programmed EUI-48 identification. Its integrated 64-byte battery-backed SRAM preserves frequently used configuration or counter data, while 1 Kbit EEPROM provides nonvolatile storage. The SPI interface allows the host to configure the device, read current time, program alarms and timers, and manage stored data over a compact serial connection. The MCP79511T-I/MS is designed for low-power embedded systems where accurate timekeeping and identity are important. Digital trimming supports calibration of the oscillator, while the battery switchover helps maintain operation when the primary supply is removed. The interrupt output can indicate alarms, timer events, or other programmed conditions, allowing the host processor to remain inactive until an event occurs. Typical applications include Ethernet-connected equipment requiring EUI-48 identification, industrial controllers, data-acquisition systems, network appliances, embedded instruments, and battery-backed telemetry products. The combination of RTC functionality, retained memory, EEPROM, and MAC identity can reduce the number of discrete components required in a design. Designers should verify the crystal, load capacitors, supply decoupling, and backup-battery interface against the manufacturer datasheet. Firmware must also account for the device address, register map, interrupt behavior, and any required calibration sequence. The available verified source data confirms the 3 V SPI RTCC function, 64-byte SRAM, 1 Kbit EEPROM, EUI-48 identity, and 10-MSOP package. This page consolidates manufacturer product information, distributor listings, interface details, and application guidance for engineers evaluating the MCP79511T-I/MS. Exact pricing, electrical limits, timing values, and pin assignments should be checked against the current Microchip datasheet before release to production.
MS32340 - Quad 25/28G CDR with Adaptive Equalization
The MS32340 is a four-channel 25.78 Gbps / 28.05 Gbps clock and data recovery (CDR) device with integrated adaptive equalization, supplied in a SIP package. Its primary verified functions are four-channel clock and data recovery, support for both 25.78 Gbps and 28.05 Gbps data rates, and adaptive equalization for channel-loss compensation. The available source identifies the device as the ms32340 (SIP) Quad 25/28G CDR with Integrated Equal, but it does not provide a manufacturer identity, official manufacturer datasheet URL, complete pinout, lifecycle status, pricing, or a detailed electrical specification table. A CDR is a signal-integrity semiconductor that recovers a usable clock from a serialized high-speed data stream and aligns data with that recovered timing reference. In the broader hierarchy, a CDR is a clock-and-timing IC, a high-speed interface component, and part of the semiconductor family used in optical and copper data links. Adaptive equalization compensates for frequency-dependent channel loss encountered when data travels through connectors, printed-circuit-board traces, cables, or other interconnect media. Integrating equalization with clock and data recovery can reduce the number of separate high-speed signal-chain blocks required. The verified MS32340 description identifies four channels and two principal rates: 25.78 Gbps and 28.05 Gbps. These rates are suitable for evaluating next-generation high-speed links, but the supplied data does not state the associated line rate standard, modulation format, reference-clock requirement, equalization reach, jitter performance, power consumption, or operating temperature. It also does not specify whether the device transmits data, receives data, or performs both directions. Those details must be obtained from the original manufacturer documentation before schematic capture or production release. The part is identified as a SIP device, but the available source does not state pin count, body dimensions, lead spacing, thermal resistance, mounting orientation, or supported package variant. Because no authoritative manufacturer datasheet was supplied, the pinout is left null rather than reconstructed from secondary listings. Similarly, the device’s RoHS, REACH, AEC-Q100, lead-free, and halogen-free status cannot be inferred from the product category. MS32340 should be treated as a specialized high-speed CDR rather than a general-purpose regulator or microcontroller. Its integrated adaptive equalization makes it a candidate for prototype evaluation in high-speed communications equipment, optical-module signal paths, backplane links, and test equipment. The key design risk is incomplete documentation: system integrators should verify all timing, reach, loss-tolerance, power, and interface specifications against the manufacturer’s approved datasheet and reference designs. This page preserves only the verified MS32340 facts and does not invent missing electrical or commercial values.
NB3N502DR2G - 14-190 MHz PLL Clock Multiplier, SOIC-8 | onsemi
The onsemi NB3N502DR2G is a 14 MHz to 190 MHz Phase-Locked-Loop (PLL) clock multiplier IC housed in an 8-pin SOIC (3.90 mm narrow body) package that accepts a 2 MHz to 50 MHz fundamental-mode crystal or external reference clock and generates a low-jitter TTL/CMOS-level output clock at a precise multiple of the input reference. The device operates from a single 3.3 V or 5.0 V supply and delivers a 50 percent duty cycle output up to 190 MHz, making it a cost-effective replacement for discrete crystal oscillators in digital systems that need a multiplied reference clock. According to the onsemi datasheet, the input clock frequency range is 2 MHz to 50 MHz and the output frequency range is 14 MHz to 190 MHz with sub-nanosecond period jitter, providing clean timing for high-speed digital logic. A PLL clock multiplier is a feedback-controlled oscillator that phase-locks a Voltage-Controlled Oscillator (VCO) to a lower-frequency reference, allowing the system to derive a high-frequency clock from a low-frequency, low-cost crystal. In the broader taxonomy, the NB3N502 belongs to the clock-generator / frequency-synthesizer family of timing ICs, sitting beneath clock buffers and above generic phase-locked loops in the timing-and-signal-conditioning hierarchy of power management and signal-chain semiconductors. PLL multipliers are commonly used when a stable, low-jitter high-frequency clock is required but only a low-frequency crystal is available, or when the reference frequency must be precisely scaled to meet downstream logic requirements. Key features include TTL/CMOS-compatible output drive, internal loop filter components, and a wide industrial operating temperature range of -40 degrees C to +85 degrees C. The device integrates the PLL, VCO, and output divider on a single monolithic CMOS die, eliminating external loop-filter design. Its pin-selectable multiplier ratios (when applicable) and standard SOIC-8 footprint simplify drop-in replacement of legacy clock-generator circuits. The NB3N502DR2G is also Pb-free and supplied on a 2500-piece reel, suitable for high-volume surface-mount assembly. The architecture uses a digital phase-frequency detector driving an on-chip charge pump and VCO, with the multiplied output divided back to the reference frequency to close the loop. This analog PLL approach yields much lower jitter than simple frequency doublers built from XOR gates or delay lines, which is critical for downstream microcontrollers, FPGAs, and communications ASICs that derive internal clocks from the multiplied reference. The single-supply 3.3 V/5 V operation also simplifies integration into mixed-voltage designs without level shifters on the supply rail. Typical applications include replacing crystal oscillators in networking equipment, generating CPU/FPGA reference clocks in embedded systems, producing pixel clocks for video and display controllers, and providing low-jitter timing in industrial automation and instrumentation. The NB3N502DR2G is also widely used as a low-cost clock source for microcontroller (MCU) families that require an external multiplied reference. When designing with the NB3N502DR2G, ensure the input reference drive level meets the datasheet-specified VIH/VIL thresholds and that the PCB layout keeps the input trace short to minimize reflections. Decouple VDD3VCC with a 0.1 ohm ceramic + 10uF bulk capacitor pair, and place the load capacitor (when applicable) close to the IC to control output rise and fall characteristics.
NB3V1104CMTTBG - 1:4 LVCMOS Fanout Buffer 250MHz | onsemi
The onsemi NB3V1104CMTTBG is a 1:4 LVCMOS clock fanout buffer rated for operation up to 250 MHz, supplied in an 8-pin WDFN (2x2 mm) package. It accepts 3.3 V, 2.5 V, or 1.8 V LVCMOS input levels and produces four low-skew LVCMOS outputs. The device is part of the modular NB3V110xC family of low-skew, general-purpose LVCMOS clock buffers from onsemi. A clock buffer (or clock fanout buffer) is a timing component that receives a single reference clock on its input and reproduces multiple copies of that clock on its outputs. Clock buffers sit between an upstream clock source - such as a crystal oscillator, PLL, or serializer - and downstream loads such as processors, FPGAs, memory controllers, and switch fabrics. Their primary function is to preserve signal integrity while distributing a low-jitter, low-skew clock to multiple destinations that cannot share a single trace. Key features of the NB3V1104CMTTBG include very low additive jitter, low output-to-output skew within the 1:4 fan-out, and a wide operating temperature range. The 8-WDFN package measures only 2x2 mm, making it suitable for dense PCB layouts in networking, computing, and consumer electronics. Onsemi's NB3V110xC family is designed so that the 1:2, 1:3, 1:4, 1:6, and 1:8 variants share pin compatibility, which simplifies board bring-up and second-source qualification. Architecturally, the part uses a differential-input/single-ended output stage optimized for LVCMOS signaling. The input is designed to be driven by a 3.3 V, 2.5 V, or 1.8 V LVCMOS source, and the outputs swing rail-to-rail into standard LVCMOS receivers. Internal bias networks and ESD protection support robust operation in industrial environments. Typical applications include Ethernet switches and routers, fan-out for FPGA reference clocks, server and storage backplanes, set-top boxes, and PCI Express cards. The wide operating voltage range makes it a flexible choice when the system clock rail varies between 1.8 V and 3.3 V across board revisions. When designing with this device, ensure the output trace lengths to matched outlets are length-matched within the application's tolerance window to control board-induced skew. Place a 0.1 uF decoupling capacitor close to the VDD pin and provide a solid ground return to minimize jitter contribution from the supply. This page synthesizes distributor pricing as of 2026-10-09, drop-in alternatives across vendors, and practical design notes that are not collected in any single manufacturer document.
NBXDBB017LNHTAG - 156.25/312.5 MHz LVPECL XO Oscillator | onsemi
The onsemi NBXDBB017LNHTAG is a 3.3 V dual-frequency LVPECL crystal oscillator (XO) housed in a 6-pin CLCC (7x5 mm) surface-mount package. It provides selectable output frequencies of 156.25 MHz and 312.5 MHz using a high-Q fundamental crystal combined with an integrated PLL multiplier, delivering ultra-low jitter and phase-noise performance required for high-speed serial links. A crystal oscillator (XO) is a self-contained timing device in which a quartz resonator and an active oscillation/buffering circuit are co-packaged; unlike a bare crystal, an XO outputs a clean, conditioned logic-level clock and does not require external load capacitors. Within the broader clock-tree hierarchy, XOs sit above crystal units and below clock generators/buffers (and fanout buffers like LVPECL drivers), serving as the primary frequency reference for Serializer/Deserializer (SerDes) PHYs, FPGAs, network processors, and ASICs in telecom, datacom, and embedded systems. Key features of the NBXDBB017LNHTAG include a 3.3 V single supply, LVPECL differential outputs, frequency select via a control pin, typical RMS jitter on the order of single-digit picoseconds over 12 kHz to 20 MHz, and an industrial operating temperature range suitable for outdoor and uncontrolled thermal environments. The 6-CLCC package offers a small footprint with a hermetic ceramic body, which improves reliability under thermal cycling and mechanical stress compared with plastic molded oscillators. Technically, the device pairs a fundamental-mode crystal with a PLL multiplier block that synthesizes the second harmonic (312.5 MHz) from the 156.25 MHz fundamental; the output stage is an LVPECL driver that produces complementary ECL-style swings around a VCC-1.3 V common-mode voltage. LVPECL is preferred at these data rates because it provides low common-mode noise, high edge rates, and good immunity to supply noise relative to LVCMOS at multi-hundred-MHz frequencies. Typical applications include 1G/10G Ethernet PHY reference clocks, Fibre Channel and SONET/SDH line cards, PCIe and RapidIO reference inputs, FPGA logic-clock inputs, and clock trees for switches and routers. The selectable dual frequency lets one BOM line serve boards that need both the base rate and the doubled rate. When designing with this part, place it adjacent to the receiver IC, keep LVPECL traces length-matched within a few mils, terminate each side with the standard 50 ohm to VTT network, and provide solid 0.1 uF plus bulk-decoupling on the supply pin. The frequency-select pin should be tied directly to logic, not floated, to avoid undefined output behavior. This page synthesizes distributor pricing, drop-in compatible onsemi alternates, and practical PCB-layout guidance that the bare manufacturer datasheet does not consolidate in one place.
NE555P - Single Precision Timer, 100kHz, DIP-8 | Texas Instruments
The Texas Instruments NE555P is a precision bipolar timer IC in an 8-pin PDIP (DIP-8) package, capable of producing accurate time delays or oscillation from microseconds to hours. It supports astable (oscillator) and monostable (one-shot) operating modes, with timing set by a single external resistor-capacitor network. The 555 timer is a classic analog building block that combines a precision voltage divider, two comparators, an internal flip-flop, and a high-current discharge transistor into one 8-pin device. Its role in modern electronics places it under the clock & timing / signal generation hierarchy, serving as a low-cost alternative to microcontroller timing or dedicated oscillator chips in non-critical timing paths. Key specifications include a maximum operating frequency of 100 kHz (up to 500 kHz depending on datasheet parameter), a supply voltage range of 4.5V to 16V, and a TTL-compatible output that can sink or source up to 200 mA. The bipolar architecture provides robust output drive capability, making it suitable for directly driving relays, LEDs, buzzers, and other loads without an external driver stage. The internal design uses three 5kΩ resistors forming the reference divider (giving the 555 its namesake), a discharge transistor for capacitor reset, and a set/reset flip-flop that latches trigger and threshold events. Threshold and trigger levels are set at 2/3 VCC and 1/3 VCC respectively, providing predictable timing independent of supply voltage within specified limits. Typical applications include precision timing circuits, pulse generation, sequential timing, missing-pulse detection, and LED/relay drivers. The 200 mA output drive eliminates the need for buffer transistors in most direct-load designs, while the bipolar simplicity ensures reliable operation in hobby, educational, and industrial control systems. When designing with the NE555P, add a 0.01 μF bypass capacitor directly across the VCC and GND pins to suppress supply noise that could couple into the timing comparators. For astable oscillators, ensure the timing capacitor has low leakage (film or quality electrolytic) because leakage current directly degrades frequency accuracy above 10 kHz. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
NE555PE4 - 555 Timer 100kHz PDIP-8 Precision | Texas Instruments
The Texas Instruments NE555PE4 is a single-precision 555-type timer/oscillator IC housed in an 8-pin PDIP (through-hole) package, supporting timing from microseconds to hours with astable or monostable operating modes. The part delivers a frequency range from 1mHz to 100kHz, operates from 4.5V to 16V, and sources/sinks up to 200mA at TTL-compatible output levels. What is a 555 timer? A 555 timer is a highly integrated analog building block that combines a voltage divider, two comparators, an RS flip-flop, and a discharge transistor into one IC. It belongs to the broader clock-and-timing IC family (clock & timing IC > programmable timer > 555 timer > bipolar timer IC), sitting alongside counters and PLL devices. Within a power-and-signal chain, the 555 timer provides a low-cost means of generating precise time delays, square waves, and pulses, making it a foundational part of hobby, industrial, and educational electronics. Key features include adjustable duty cycle, TTL-compatible output that can both sink and source up to 200mA, astable/monostable operating modes, and timing accuracy of typically better than 1% with stable external RC components. The internal architecture uses a precision voltage divider (three 5k resistors - hence '555'), two comparators, a flip-flop, and an open-collector discharge transistor, all of which are accessible via the eight external pins. Typical applications include pulse generation, sequential timing, precision timing, missing-pulse detection, bounce-free switches, linear ramp generators, and PWM modulators. Industrial designers favor the NE555PE4 because of its rugged bipolar design and wide supply tolerance. A common design consideration is output current capability: the device can sink/source up to 200mA, so a small heat-sinking consideration applies when operating at high duty cycles near the supply rails. Designers should also keep the discharge transistor's collector voltage within ratings and ensure timing capacitors have low leakage to maintain accuracy. Compared to CMOS variants such as the TLC555, the bipolar NE555 draws more quiescent current but offers higher output drive. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, helping engineers rapidly evaluate fit and source the NE555PE4 for new or legacy designs.
PCA8525TKX - Nano-Power Automotive RTC IC, I2C | NXP
The NXP Semiconductors PCA8525TKX is a high-accuracy, nano-powered Real Time Clock (RTC) and calendar IC with integrated temperature compensation, an I2C-bus interface, and a temperature rating up to 125 C in a 10-lead HVSON package. It is the first RTC IC with an external crystal to feature a default temperature compensation engine, selectable between crystal curvature coefficients of -0.035 ppm/degC2 or -0.04 ppm/degC2. An RTC (real-time clock) IC is a timekeeping device that maintains seconds, minutes, hours, day, weekday, month, and year information with a 32.768 kHz watch crystal. Within the power-management and timing semiconductor hierarchy, RTC ICs form a specialized subset of clock and timing ICs optimized for ultra-low standby current rather than frequency output. RTCs run continuously even when the main processor is off, so battery-backed timekeeping accuracy and supply current are their defining metrics. Key features of the PCA8525 include nano-power supply current for extended battery life, an integrated digital temperature compensation engine that can deliver up to 5x better timekeeping accuracy than a standard uncompensated RTC, and a selectable crystal temperature model. An aging offset register further corrects long-term crystal drift, keeping timekeeping error within minutes per year rather than tens of minutes. The compensation engine periodically measures the die temperature and digitally adjusts the clock, compensating the parabolic frequency-versus-temperature characteristic of tuning-fork crystals. Because compensation is performed on-chip, no external thermistor, lookup table, or MCU overhead is needed. The I2C interface transfers all addresses and data serially, simplifying integration with any host microcontroller. Typical applications include automotive body control modules and gateway ECUs rated to 125 C ambient, smart meters, industrial dataloggers, and battery-powered IoT endpoints where both accuracy and nano-amp timekeeping current are critical. The automotive qualification makes it especially suitable for under-hood-adjacent modules requiring AEC-grade reliability. Design consideration: crystal selection matters. The compensation engine assumes a typical tuning-fork crystal model; verify that the chosen crystal's curvature coefficient matches the selectable -0.035 or -0.04 ppm/degC2 setting for guaranteed accuracy. This page synthesizes distributor sourcing data, drop-in same-family alternatives, and practical design notes not found in the manufacturer datasheet.
PCF2123BS/1 - SPI RTC Calendar IC | 16-HVQFN | NXP
The NXP Semiconductors PCF2123BS/1 is a CMOS Real-Time Clock (RTC) and calendar with a Serial Peripheral Interface (SPI-bus) operating up to 6.25 Mbps, supplied at 1.1 V to 5.5 V, packaged in a 16-pin HVQFN exposed-pad package. It integrates time-of-day, calendar, alarm, timer and interrupt functions with an integrated 32.768 kHz crystal resonator space on chip, drawing less than 100 nA at 2.0 V for ultra-low standby power. A Real-Time Clock (RTC) is a dedicated integrated circuit that maintains accurate time and date information independent of system power. RTCs sit within the broader category of power management companions and timing ICs, working alongside MCUs, FPGAs and SoCs to provide timekeeping during main-power-off conditions through a small backup cell or supercapacitor. They typically expose time registers in BCD format and communicate over serial buses such as I2C or SPI. The PCF2123BS/1 uses SPI for higher throughput where speed and noise immunity matter. Key features include a wide 1.1 V to 5.5 V supply range, less than 100 nA typical current consumption at 2.0 V, integrated alarm and timer functions, an interrupt output, and a wide operating temperature range suitable for industrial environments. The device is supplied in a compact 3 mm x 3 mm HVQFN-16 plastic package with a thermal pad, drawing less than 0.2 microW of power to support battery-backed operation. The PCF2123BS/1 uses CMOS logic and on-chip tuning, allowing timekeeping accuracy to be compensated via load and trim registers. The SPI interface supports a maximum data rate of 6.25 Mbps, enabling fast register access by host processors. The integrated power-on reset and trickle charger functionality simplify backup power design. Typical applications include battery-backed timekeeping in metering, data loggers, industrial controllers, white goods and IoT sensor nodes, and any portable embedded system that needs a low-power accurate wall-clock reference independent of the main MCU. When designing with this device, place a 100 nF decoupling capacitor close to VDD and connect the exposed thermal pad to a clean ground pour. Always handle the SPI chip-select correctly to avoid bus contention with other peripherals on the same SPI bus. The NXP product page notes End-of-Life status, so check availability before new designs. This page synthesizes distributor pricing, drop-in compatible alternatives, and practical design notes not consolidated in the manufacturer datasheet, providing engineers with a faster decision path.
PCF85263ATT/AJ - Tiny RTC I2C 400kHz, Battery Switch-Over | NXP
The NXP Semiconductors PCF85263ATT/AJ is a CMOS Real-Time Clock (RTC) and calendar optimized for ultra-low power consumption with automatic battery switch-over on main power loss, supplied in an 8-pin TSSOP (also called 8-MSOP, 3.00 mm width) package. It communicates through a 400 kHz I2C-bus and integrates three time-log registers, a clock output, two independent alarms, and a timestamp input that records power-down/power-up transitions. Programmable via 16-bit registers, the PCF85263ATT/AJ provides century, year, month, day, weekday, hours, minutes, and seconds with leap-year correction up to the year 2099, making it suitable for long-lifecycle embedded designs. An RTC (Real-Time Clock) is a low-power oscillator-plus-counter peripheral that maintains wall-clock time independently of the host MCU. RTCs are members of the broader timer/clock IC family, which also includes timer ICs and stop-watch counters. In the system hierarchy, an RTC sits beneath power management and above discrete passives, providing a battery-backed time reference for microcontrollers that would otherwise need to keep time via software timers and a separate 32.768 kHz crystal. By integrating the crystal load capacitors, the battery switch-over MOSFET, and the I2C interface into a single IC, the PCF85263ATT/AJ reduces BOM count and PCB area compared to discrete RTC designs. Key features include 4 time-of-day alarms with timestamp, integrated 32.768 kHz crystal load capacitors (12.5 pF), supply voltage range of 0.9 V to 5.5 V with separate battery supply input, low typical current of 0.55 uA at VDD=3.3 V, and an operating temperature range of -40C to +85C. Three time-log registers are triggered by battery switch-over and input-driven events, supporting forensic power-event capture. The device can also be configured as a stop-watch (elapsed time counter), adding flexibility for metering and instrumentation use cases. The PCF85263A architecture uses a low-power 32.768 kHz crystal oscillator with selectable load capacitance, a BCD-based time counter chain, and a power-management block that arbitrates between VDD and the backup battery. The I2C-bus runs up to 400 kHz in fast mode, and the slave address is fixed (per the manufacturer datasheet). The 8-TSSOP footprint (TSSOP-8 / MSOP-8 outline, 3.0 mm body) is pin-compatible with industry-standard RTCs, enabling drop-in PCB reuse. Typical applications include smart metering (electricity, gas, water), IoT battery-powered sensors, industrial data loggers, white goods, point-of-sale terminals, medical portable devices, and any embedded system requiring timekeeping during main-power loss. The wide 0.9 V to 5.5 V supply range lets the same part serve as backup for a coin cell, a supercapacitor, or a rechargeable battery. When designing with this device, place the 32.768 kHz crystal as close to the XIN/XOUT pins as possible, keep the traces short and symmetric, and add a guard ground to minimize noise coupling. The VBACKUP pin requires a series resistor per the manufacturer datasheet when charged by a supercapacitor. This page synthesizes distributor pricing, drop-in pin-compatible alternatives, and practical design notes not found in the manufacturer datasheet. Citations are anchored to the NXP PCF85263A datasheet (per the manufacturer datasheet), DigiKey product page, and Mouser product page.
PCF8563BS/4,118 - 1mA I2C RTC | 400kHz | HVSON-10 | NXP
The NXP PCF8563BS/4,118 is a CMOS Real-Time Clock (RTC) and calendar optimized for low power consumption, providing year, month, day, weekday, hours, minutes, and seconds based on an external 32.768 kHz quartz crystal. Housed in a 10-pin HVSON (3x3 mm, SOT650-1) exposed-pad package, it communicates via a 400 kHz I2C (2-wire) serial interface and operates from a 1.8 V to 5.5 V supply. According to the NXP datasheet, the device integrates a programmable clock output, an interrupt output, and a voltage-low detector in a footprint of approximately 3x3 mm. What is an RTC? A Real-Time Clock is a dedicated integrated circuit that maintains accurate wall-clock time (date and time) independent of the main system processor, typically referenced to a 32.768 kHz quartz crystal. RTCs sit hierarchically as follows: RTC -> clock/calendar IC -> timing device -> mixed-signal IC -> semiconductor. Unlike software-based timekeeping derived from a microcontroller's oscillator, an RTC continues counting while the host MCU is in deep sleep or powered down, making it the standard solution for battery-backed time-of-day tracking. Key features of the PCF8563BS/4,118 include a maximum clock supply current of 1 mA typical at 32 kHz, an integrated I2C slave interface running up to 400 kHz, a programmable square-wave clock output (32.768 kHz, 1024 Hz, 32 Hz, 1 Hz), an open-drain interrupt output, and an on-chip power-on reset plus voltage-low detector. These features let the host MCU wake only on calendar or alarm events, which minimizes total system energy use. The device uses a low-power CMOS architecture with separate oscillator and timing registers, achieving the typical sub-1 microampere backup current needed for coin-cell battery operation. All 16 RTC registers and the 32.768 kHz trimming circuit are accessed over the standard I2C bus at slave address 0x51 (101 0001b), enabling easy drop-in replacement into designs that already use the PCF8563 footprint. Typical applications include battery-backed wall-clock modules for metering and data loggers, timekeeping in IoT sensor nodes, alarm and timer functions in white goods, point-of-sale terminals, and any embedded system requiring calendar accuracy during MCU sleep or power loss. The wide 1.8 V to 5.5 V supply range also makes it suitable for 3.3 V and 5 V microcontroller rails. When designing with the PCF8563, ensure the 32.768 kHz crystal load capacitance matches the oscillator's specified CL (typically 12.5 pF) and add a small decoupling capacitor on VCC. The exposed thermal pad of the HVSON-10 package should be soldered to the ground plane for mechanical stability and improved thermal dissipation. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, giving engineers a single source for sourcing, selecting, and implementing the PCF8563BS/4,118.
PCF8593T/1,118 - I2C RTC Clock/Calendar, 8-SOIC | NXP Semiconductors
The NXP Semiconductors PCF8593T/1,118 is a CMOS Real-Time Clock (RTC) and calendar circuit optimized for low power consumption, housed in an 8-pin SOIC (SOT96-1) package. The device provides an 8-bit serial interface over the industry-standard I2C (2-wire) bus, supports a supply voltage range of 2.5 V to 6.0 V, and integrates a 32.768 kHz oscillator circuit that drives timekeeping, calendar, and counter functions in the first 8 bytes of internal RAM. A Real-Time Clock (RTC) is a dedicated integrated circuit that keeps track of current time and date (typically seconds, minutes, hours, days, weekdays, months, years) even when the main system power is removed, usually backed by a small battery or supercapacitor. Within the broader component taxonomy, an RTC sits under the clock & timing category, which itself is a subset of integrated circuits. RTCs are essential building blocks for any embedded design that needs time-of-day awareness: from data loggers and metering equipment to industrial controllers and consumer appliances. The PCF8593 represents the classic low-power serial-RTC architecture that has dominated I2C-based designs since the 1990s. Key features of the PCF8593T/1,118 include 240 bytes of general-purpose static RAM available beyond the timekeeping registers, a programmable 32.768 kHz oscillator with on-chip load capacitors, automatic word-address increment after each read/write byte, a 24-hour or 12-hour format option, and low standby current in the microamp range. The 8-SOIC package is industry standard (3.90 mm body width), making the device drop-in compatible with the classic 8-pin DIP footprint pad layout when designed with the SOIC land pattern. The internal address counter eliminates the need for burst-mode addressing in firmware, simplifying I2C driver code. Typical applications include battery-backed wall-clock modules for appliances, time-of-day stamping in metering and data-acquisition systems, low-power sensor nodes that wake periodically and need an accurate timestamp, industrial programmable logic controllers (PLCs) that log events, and consumer electronics such as VCRs, set-top boxes, and audio gear that must retain clock time across power cycles. When designing with this part, place the 32.768 kHz watch crystal as close as possible to the OSCO/OSCI pins to minimize parasitic capacitance, ensure the I2C pull-up resistors are sized correctly for the bus capacitance, and keep the backup battery path well-decoupled to survive brown-outs. The part is approaching end-of-life per the NXP product page, so designers should evaluate the PCF85263A or PCF8563 as pin-compatible modern replacements for new designs.
PI6C557-03AQE - PCIe 2.0 Spread Spectrum Clock Generator | Diodes Inc
The Diodes Incorporated PI6C557-03AQE is a spread-spectrum clock generator compliant with PCI Express 2.0 and Ethernet timing requirements, packaged in a 16-pin QSOP (also referenced as 16-SSOP by some listings). The part accepts a 25 MHz fundamental-mode crystal reference and produces two pairs of differential HCSL outputs at user-selectable frequencies of 25 MHz, 100 MHz, 125 MHz, and 200 MHz. Spread-spectrum modulation is applied through a proprietary PLL architecture to substantially reduce electromagnetic interference (EMI) on the system reference clock. A spread-spectrum clock generator is a timing device that intentionally modulates the output frequency around a center value at a low modulation rate. By spreading the spectral energy of the clock over a wider bandwidth, peak EMI emissions are reduced, helping designs pass regulatory compliance tests such as FCC Class B and CISPR 22. Within the broader clock-and-timing IC category, this part sits in the PCIe clock-generator subcategory alongside PLLs, frequency synthesizers, and zero-delay buffers. Key features include a 25 MHz crystal input, two HCSL (current-mode differential) output pairs, on-chip termination support, output enable / power-down control, and selectable spread-spectrum depth. HCSL is the signaling standard required by PCIe 2.0/3.0 reference clocks and is also used in mainstream Ethernet PHYs. The internal PLL is sourced from Pericom's spread-spectrum technology and maintains low cycle-to-cycle jitter even with active modulation. Typical applications include PCIe add-in cards (network, storage, graphics), embedded systems needing EMI-controlled 100 MHz reference clocks, Ethernet switches and NIC reference rails, and industrial PCs where the part's compliance footprint helps shorten EMI qualification cycles. The device's small 16-QSOP footprint is suitable for compact motherboard layouts. When designing with the PI6C557-03AQE, follow PCIe CEM routing guidelines for the HCSL outputs - 85 ohm differential traces, AC coupling capacitors at the receiver, and length matching within the PCIe spec. The 25 MHz crystal must be fundamental-mode with a load capacitance appropriate for the on-chip oscillator.
PI6CG33A06ZLFEX - 6-Output PCIe 7.0 Clock Generator | Diodes Inc
The Diodes Incorporated PI6CG33A06ZLFEX is an ultra-low-jitter, 6-output PCIe 5.0/6.0/7.0 clock generator with integrated on-chip output termination, housed in a 40-pin VQFN (5 mm x 5 mm) package. It accepts a reference input and generates 25 MHz and 100 MHz differential outputs while maintaining sub-30 fs RMS phase jitter that outperforms the 80 fs CK440Q PCIe specification. A clock generator is an integrated circuit that synthesizes one or more precise timing signals from a reference oscillator, providing the heartbeat that synchronizes CPUs, memory, and high-speed serial links. In the broader IC hierarchy it sits below clock buffers and above generic PLLs, and it belongs to the timing-IC family within power management and signal-chain semiconductors. Key features include six differential outputs with individual OE (output enable) pins for granular power management, integrated 85 ohm on-chip termination that eliminates 24 external resistors, 300 ns SMBus 2.0-compatible data hold time, and support for PCIe Gen 1/2/3/4/5/6/7 standards. The on-chip termination simplifies board layout and shrinks BOM count by 24 resistors versus discrete implementations. The device uses Diodes' proprietary PLL architecture with fractional-N feedback to achieve the jitter performance required for PCIe 7.0 while maintaining backward compatibility with PCIe 5.0 and 6.0. Each output pair is independently controllable through SMBus registers, which is essential for modern servers that need to power down unused PCIe lanes to meet energy-efficiency targets. Typical applications include AI server motherboards, NVMe SSD controllers, networking switches, high-performance computing accelerator cards, and CXL-attached memory modules. The compact VQFN-40 5x5 mm footprint also makes the part attractive for space-constrained add-in cards and OCP accelerator designs. When designing with this device, follow the recommended power-rail decoupling layout: 1 uF and 0.1 uF ceramic capacitors placed within 2 mm of each supply pin. Maintain 100 ohm differential impedance on each output pair and route length-match within 5 mils to preserve jitter performance.
PI6CG33A06ZLFEX-13R - 6-Output PCIe 5.0/6.0/7.0 Clock Generator | Diodes Inc
The Diodes Incorporated PI6CG33A06ZLFEX-13R is a 6-output ultra-low jitter clock generator designed to meet the demands of the PCI Express 7.0 specification while maintaining backwards compatibility with PCIe 5.0 and 6.0. It delivers 100 MHz HCSL outputs (and 25 MHz reference) from a single reference input, housed in a 40-pin VQFN (5x5 mm) package with integrated on-chip termination that eliminates up to 24 external resistors. Each output features an individual OE (output enable) pin for granular power management, and the device supports SMBus 2.0 programming with 300 ns data hold time for legacy compatibility, plus 0 ns hold time for newer SMBus revisions at 100 kHz and 400 kHz. A clock generator IC is a semiconductor device that takes a low-jitter reference clock (typically from a crystal oscillator or external source) and produces one or more synchronized output clocks, often at multiplied or divided frequencies and with specific output formats (HCSL, LVCMOS, LVDS, LVPECL). PI6CG33A06ZLFEX-13R belongs to the timing generator family, which sits in the broader hierarchy of clock and timing ICs -> clock generators -> PCIe timing components -> power management and system timing for computing and storage platforms. PCIe clock generators are essential building blocks in servers, workstations, NVMe storage, networking switches, and graphics cards where deterministic jitter performance is required by the PCI-SIG specification. Key features include ultra-low additive jitter to meet PCIe 7.0 jitter budgets, integrated 100-ohm differential on-chip termination matching PCIe HCSL impedance directly, six individually-controlled HCSL outputs operating at 100 MHz, and a 25 MHz reference output for downstream devices. The 3.3 V supply simplifies integration with common server and storage platform rails. SMBus programming allows frequency, format, output enable, and spread-spectrum parameters to be configured in-system. From an architectural perspective, the PI6CG33A06 uses a PLL (phase-locked loop) synthesizer to multiply a 25 MHz crystal reference into six phase-aligned 100 MHz HCSL outputs. The on-chip termination eliminates the need for external 100-ohm resistor networks typically required on each HCSL pair, significantly reducing BOM count and PCB complexity while preserving the precise impedance matching required by PCIe 5.0/6.0/7.0 physical-layer compliance testing. Typical applications include PCI Express Gen5/Gen6/Gen7 server riser cards, NVMe storage controller clocking, workstation motherboards, 5G base-station backplane clock distribution, and AI accelerator PCIe retimer cards. The 100 MHz HCSL output format is required by PCIe CEM specification for all downstream add-in cards and baseboard connections. When designing with this device, place 0.1 uF decoupling capacitors as close as possible to each VDD pin and follow the layout recommendations in the manufacturer datasheet. Maintain 100-ohm differential trace impedance on each HCSL pair and minimize stubs to preserve jitter margin. Use the SMBus lines carefully with proper pull-up resistors and keep them away from switching noise sources. This page synthesizes distributor availability and pricing, drop-in PCIe alternatives from Diodes and other vendors, and practical layout notes not found in the bare datasheet, giving engineers a single decision point for PCIe 7.0 clock tree selection.
PT7C4339WEX - Low Power I2C Real Time Clock | Diodes Inc
The Diodes Incorporated PT7C4339WEX is a low-power consumption I2C Real-Time Clock (RTC) module with clock/calendar functionality, supplied in an 8-pin SOIC (0.154", 3.90 mm body width) package. It integrates a serial interface, power-fail detector, programmable square-wave output, and a 56-byte non-volatile SRAM for backup storage, all on a single CMOS die. The part is widely used as a drop-in replacement for legacy RTCs in industrial controllers, metering, and embedded systems. Source: Diodes Incorporated product page (PT7C4339 datasheet family) and distributor listings on DigiKey and Mouser as of 2026-10-10. A Real-Time Clock (RTC) is a dedicated integrated circuit that keeps track of wall-clock time - seconds, minutes, hours, day, date, month, and year - independent of the host processor. RTCs are essential in any embedded system that must maintain accurate time during power-down, power-up events, or processor sleep modes. The PT7C4339 specifically implements the I2C (Inter-Integrated Circuit) 2-wire serial protocol, communicating on a standard I2C bus at speeds up to 400 kHz. Key features include automatic leap-year compensation up to year 2100, a wide operating voltage range, low timekeeping current draw in the microamp range, and an integrated power-fail circuit that automatically switches to a backup battery when VCC drops below a programmable threshold. The PT7C4339 maintains time accuracy of typically +/-2 ppm at 25C, equivalent to a drift of less than one minute per year. The 8-SOIC package (3.90 mm body) is a JEDEC-standard surface-mount form factor compatible with hand-soldering and standard reflow profiles. The PT7C4339 communicates via the I2C bus with a fixed slave address and registers arranged in BCD (Binary Coded Decimal) format. Engineers typically access the device through I2C read/write transactions, where the master first sends the device address with the R/W bit, then the register pointer, and finally the data byte. Built-in address recognition and write-protect logic protect against unintended writes during brown-out events. Typical applications include battery-backed timekeeping in metering and datalogging, embedded industrial controllers, point-of-sale terminals, and consumer electronics that need accurate wall-clock time without burdening the main microcontroller. The wide VCC tolerance makes it equally suitable for 3.3V microcontroller systems and legacy 5V designs. When designing with the PT7C4339, always observe the bypass capacitor recommendation: place a 0.1 uF decoupling cap as close as possible to VCC. For backup battery operation, ensure the backup cell voltage stays within the device-specified VBACK range, and consider the trickle-charge resistor selection carefully to avoid damaging lithium coin cells. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in a single manufacturer datasheet - the analysis is based on cross-checking the Diodes PT7C4339 datasheet family, the Pericom legacy datasheet (PT7C4339WEX is sold both as Diodes Incorporated and historically as Pericom Semiconductor), and current distributor inventory as of 2026-10-10.
RX8900CE - DTCXO RTC I2C 10-SMD | Epson | TCXO
The Epson RX8900CE is a real-time clock (RTC) module integrating a high-precision digital temperature compensated crystal oscillator (DTCXO) with built-in power switching and an I2C interface in a compact 10-pin SMD package. It provides ±5 ppm (approximately ±2 minutes per year) timekeeping accuracy across the full -40 °C to +85 °C operating range, with a 1.6 V to 5.5 V supply range and selectable I2C address via the I2C_SEL pin. A Real-Time Clock (RTC) is a low-power integrated circuit that maintains accurate wall-clock time (seconds, minutes, hours, days, date, month, year) even when the host system is powered off, typically backed by a battery or supercapacitor. RTCs fall within the broader category of clock/calendar ICs, themselves a subset of power management and timing components. By integrating a TCXO and the crystal into one SMD module, the RX8900CE eliminates the need for an external 32.768 kHz quartz and the associated load-capacitor design trade-offs, simplifying layout and BOM. Key features include ±5.0 ppm frequency stability over temperature, integrated 32.768 kHz DTCXO with on-chip crystal, an automatic power-switching circuit that seamlessly transitions between primary VDD and backup battery, two user-programmable alarm / time-update interrupts, and an I2C-bus interface (400 kHz Fast Mode compatible). Additional functions include a 32.768 kHz output pin for clocking an external MCU, century bit for dates beyond 2099, and a 12/24 hour timekeeping mode. Internally the device uses a 32.768 kHz AT-cut crystal in conjunction with a fractional-N DTCXO compensation loop. The compensation register is trimmed during factory calibration to suppress the parabolic frequency-temperature curve, leaving a residual error dominated by linear slope. This architecture delivers near-OCXO accuracy in a module that costs and consumes roughly the same as an uncompensated RTC. Typical applications include industrial IoT gateways and data loggers, metering and smart-grid endpoints, automotive infotainment and telematics requiring wide-temp accuracy, security/alarm panels with battery backup, and consumer electronics that must retain time during power loss. The wide -40 °C to +85 °C operating range makes it a strong fit for outdoor and automotive-grade designs. When designing with the RX8900CE, ensure the backup battery is sized so that the VDD-to-BAT switchover voltage (typical 2.2 V) is not crossed during a normal power cycle. Decoupling must include a 0.1 µF ceramic close to VDD; the integrated crystal removes the need for external load capacitors but the I2C bus still requires pull-ups. Allow the TCXO ~2 s after VDD restoration to deliver its full accuracy. This page synthesizes distributor pricing, drop-in alternatives within the same Epson RX-89xx family, and practical design notes that are not consolidated in the manufacturer datasheet.
SI52208-A01AGM - 8-Output PCIe Gen 1-6 Clock Generator | Skyworks
The Skyworks Solutions (formerly Silicon Labs) SI52208-A01AGM is an 8-output, low-power PCI Express clock generator IC delivering 100 MHz HCSL-compatible clocks with 0.085 ps RMS phase jitter for PCIe Gen 1/2/3/4/5/6 and SRIS applications, housed in a 48-pin QFN (6x6 mm) package with exposed thermal pad. The device operates from a 1.5 V to 1.8 V core supply and provides individually-controlled hardware enable pins plus I2C programmability for output enable, spread spectrum control, and frequency select. A PCIe clock generator is a specialized timing IC that produces the reference clocks required by PCI Express lanes on a motherboard or add-in card. Clock generators sit in the broader hierarchy of clock and timing ICs -> frequency synthesizers -> PLL-based timing -> semiconductor, and they are essential whenever multiple downstream devices (root complex, switch, retimer, endpoint) must be fed a low-jitter, spec-compliant reference. The Si522xx family (Si52212/08/04/02) is purpose-built for this role and integrates a fractional-N PLL, output dividers, and HCSL drivers on a single silicon die. Key features include 8 differential HCSL outputs, hardware Output Enable pins for each output pair, Spread Spectrum Enable for EMI reduction (down-spread of -0.25% / -0.5% typical), selectable 100 / 133 / 200 MHz output frequencies via FREQ_SEL pin, low-power standby mode, and I2C control of all major parameters. Typical jitter is 0.085 ps RMS (12 kHz - 20 MHz) which exceeds the PCIe Gen 6 specification with margin, and supply current is approximately 60-90 mA depending on output loading and enabled channel count. Architecturally, the Si52208-A01 uses a fractional-N PLL with an integrated reference, divider chain, and eight push-pull HCSL output buffers. The 48-QFN exposed pad provides a low thermal resistance path for the moderate power dissipation. The combination of individual OE pins, hardware SSEN, and I2C control makes the device suitable for both legacy strap-controlled designs and modern software-managed platforms. Typical applications include desktop and server PCIe root complexes, workstation motherboards, NVMe SSD controllers, PCIe retimer cards, network switches with PCIe fabric, and embedded compute platforms. The 100 MHz default and SRIS compliance support both common-clock and independent-refclk topologies required by modern server platforms. When designing with this part, observe the HCSL termination requirement: each differential pair needs a 100 ohm differential near-end termination to VTT, and the Si52208's integrated current-mode drivers source the necessary bias current. Decouple VDD with 0.1 uF and 1 uF ceramics placed within 2 mm of the supply pins, and stitch the exposed pad with at least nine thermal vias for heat spreading. This page synthesizes distributor pricing, same-family drop-in alternatives (Si52212, Si52204, Si52202), cross-brand equivalents (Renesas 9FGL08, IDT 9DBL08), and practical design notes not found in the manufacturer datasheet alone.