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Productos (160)
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.
PCF8563T/5 - I2C Real-Time Clock/Calendar IC | NXP | SOIC-8
The NXP PCF8563T/5 is a CMOS Real-Time Clock (RTC) and calendar optimized for low power consumption, supplied in an 8-pin SOIC (SOT96-1 / MO-012) surface-mount package. It is accessed through a two-line bidirectional I2C-bus at a maximum clock rate of 400 kbit/s, and features a programmable clock output, an interrupt output, and an integrated voltage-low detector for backup-battery switching. The device operates from a 1.8 V to 5.5 V supply and draws only a fraction of a microampere from the backup cell. What is a Real-Time Clock IC? An RTC is a dedicated timing integrated circuit that maintains accurate wall-clock time (seconds, minutes, hours, day, date, month, year) independent of the host system, typically backed by a small backup cell or supercapacitor. RTCs belong to the broader hierarchy of clock-and-timing ICs, which includes oscillators, PLL synthesizers and timers. Within the timekeeping sub-category, I2C RTCs such as the PCF8563 sit alongside SPI and parallel-interface RTCs, providing battery-backed timekeeping for embedded designs. Key features of the PCF8563T/5 include an integrated 32.768 kHz oscillator (0.0320 MHz reference) that requires only an external quartz crystal, a BCD-coded register map for sub-second resolution free software access, a selectable 32.768 kHz or programmable frequency clock output on CLKOUT, and a low-battery detection flag. The integrated voltage-low detector automatically switches between main supply and backup source without external MOSFETs, simplifying battery-backed designs. The PCF8563 uses a CMOS process with on-chip load capacitors matched to standard 32.768 kHz tuning-fork crystals, eliminating the need for external load caps in most applications. The address-and-data I2C protocol includes automatic register-increment for sequential reads (block read of all time/date registers in one transaction) and a slave address of 0x51 (write) / 0x53 (read) fixed by the part. Typical applications include battery-backed timekeeping in metering equipment, point-of-sale terminals, data loggers, white goods and consumer electronics, industrial controllers requiring timestamps, and any embedded system needing a low-power always-on calendar function. A wide 1.8 V to 5.5 V operating range lets the same part span single-cell Li-ion designs and 5 V industrial buses. When designing with this device, reserve the SDA and SCL pins with proper pull-ups to VCC (typically 4.7 kohm at 400 kHz), and place the 32.768 kHz crystal as close to OSCI/OSCO as possible to minimize stray capacitance. Backup-battery drain is dominated by the oscillator current; check the datasheet's Ibat figure to size your backup source. This page synthesizes distributor pricing, drop-in alternatives and practical design notes not found in the manufacturer datasheet alone.
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.
PI6C557-03LEX - 200MHz PCIe Clock Generator | Diodes
The Diodes Incorporated PI6C557-03LEX is a 200 MHz PCI Express and Ethernet clock generator with two differential HCSL outputs, supplied in a 16-TSSOP package. It accepts a 25 MHz crystal input and uses Pericom PLL techniques to generate selectable 25 MHz, 100 MHz, 125 MHz, and 200 MHz clock frequencies. The verified distributor data identifies a 3.3 V supply, a -40°C to +85°C operating range, and two clock outputs. Its clock-generation and spread-spectrum functions position it within the clock and timing IC category as a phase-locked-loop-based timing device for high-speed digital systems. A clock generator produces reference and data-rate clocks for digital circuits that require stable timing, phase control, and predictable edge placement. In a PCI Express system, a spread-spectrum clock can reduce electromagnetic-interference peaks by distributing clock energy over a frequency band. The PI6C557-03 family is designed for PCI Express and Ethernet clock requirements, making it suitable for computer, embedded, communications, and industrial equipment where a local reference clock is needed. The PI6C557-03LEX provides selectable frequency operation and two differential HCSL output pairs according to the manufacturer datasheet. Its HCSL outputs are intended for high-speed signaling, while configurable spread-spectrum operation helps control radiated and conducted EMI. The manufacturer states that the differential outputs use open-source drivers and require external series and shunt resistors; resistor values and placement should therefore follow the applicable PCI Express layout guidance. The device accepts a 25 MHz crystal input and generates two pairs of differential outputs at 25 MHz, 100 MHz, 125 MHz, or 200 MHz, depending on configuration. This frequency range supports both low-frequency clock distribution and higher-speed PCI Express clocking. The 3.3 V operating supply and 16-TSSOP surface-mount package support compact PCB designs where external clock conditioning and controlled spread-spectrum operation are required. Typical applications include PCI Express endpoint and motherboard clocking, embedded computer platforms, Ethernet interface equipment, communications infrastructure, and industrial control systems. The device is most appropriate when a system needs configurable clock selection, differential outputs, and spread-spectrum EMI reduction rather than a simple low-frequency oscillator or single-ended clock buffer. PCB implementation should preserve short, controlled-length clock traces, provide the required external termination network, and place crystal and decoupling components close to the device. Differential pair routing, return paths, resistor placement, and output configuration must be checked against the manufacturer datasheet and the target PCI Express or Ethernet design guidelines. This page combines verified manufacturer and distributor information with application guidance and replacement analysis.
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.
SI52112-B4-GT 100MHz PCIe Clock Generator | Skyworks
The Skyworks Solutions SI52112-B4-GT is a 100 MHz PCI Express clock-generator integrated circuit in an 8-pin TSSOP package. According to the supplied distributor data, it provides one 100 MHz output and is categorized as an oscillator or clock-timing IC for PCI Express systems. The verified Skyworks family documentation describes Si52112-B4 as a two-output PCIe clock generator capable of supporting PCIe Gen 1, Gen 2, and Gen 3 requirements, with configurable AC parameters for signal-integrity optimization. A PCI Express clock generator is a clock-and-timing semiconductor that creates or distributes the reference clocks required by PCIe serializers, deserializers, controllers, and other digital logic. It belongs to the broader clock-generation and clock-distribution hierarchy, where accurate edge timing and low phase jitter help maintain reliable data transfer across high-speed differential links. The verified device information identifies a 100 MHz operating or output-clock figure and an 8-TSSOP surface-mount package. Skyworks states that the Si52112-B4 family can source two PCIe clocks from a 25 MHz crystal or clock input, provides frequency flexibility, and uses configurable AC parameters for signal-integrity optimization. The supplied sources also state compliance with PCIe Gen 1, Gen 2, and Gen 3 phase-jitter requirements and availability in an industrial temperature range. Typical uses include PCIe endpoint and root-complex clock trees, industrial computer expansion cards, embedded servers, storage controllers, network adapters, and test equipment that require a deterministic reference clock. The TSSOP package makes the device suitable for conventional surface-mount PCB assembly, while exact pin functions, electrical limits, output configuration, and crystal requirements should be taken from the manufacturer datasheet. When laying out a PCIe clock circuit, keep the oscillator or crystal path and clock outputs short, use controlled impedance routing for downstream links, and account for clock jitter, return loss, and power-supply noise. Confirm the package variant, pinout, output enable behavior, supply requirements, and intended PCIe generation against the official Si52112-B3/B4 datasheet before releasing a production design.
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.
SI52208-A02AGMR - 8-Output PCIe Gen 1-4 Clock Generator | Skyworks
The Skyworks Solutions SI52208-A02AGMR is an 8-output PCI Express clock generator for 1.5 V to 1.8 V PCIe Gen 1/2/3/4 and SRIS applications, housed in a 48-pin QFN (6x6 mm) package. It delivers 100 MHz, 133 MHz, or 200 MHz differential HCSL outputs with hardware- and I2C-controlled frequency selection, individual output enable pins, and integrated 85 ohm internal termination. It supports spread-spectrum enable/disable for EMI reduction, in line with PCIe Gen 1 through Gen 4 jitter requirements, plus SRIS-compliant operation. The A02 order code targets Gen 1/2/3/4 with 25 MHz LVCMOS reference input. A PCI Express clock generator is a dedicated timing IC that synthesizes the low-jitter reference clocks required by PCIe root complexes, endpoints, switches, and retimers. It belongs to the broader category of clock generators and timing ICs within the timing-and-signal-conditioning block of a computing platform, and is typically placed adjacent to the PCIe PHY or switch to minimize trace-induced jitter. Key features include a 1.5 V to 1.8 V supply range, low power consumption, hardware pin and I2C programmability for output enable and spread spectrum, and integrated 85 ohm source termination that eliminates external resistors on each differential output pair. Compliance with PCIe Gen 1/2/3/4 phase jitter and SRIS reference-clock architectures allows direct deployment in SRNS and SRIS systems without additional PLL stages. Typical applications include desktop and server PCIe slot clocking, NVMe SSD controllers, PCIe switch reference-clock trees, riser cards, and embedded-computing PCIe endpoints. The wide frequency support (100/133/200 MHz) covers Gen 1/2 (100 MHz) and Gen 3/4 (100 MHz with optional spread) plus a 25 MHz LVCMOS reference path for downstream clocking. When designing with this device, follow Skyworks reference-layout guidance for the 48-QFN exposed pad to achieve the published jitter and supply-noise performance. Decouple VDD with 0.1 microfarad plus bulk ceramic caps placed within 2 mm of the pins, and route differential pairs to maintain 100 ohm differential impedance with matched length within 5 mils. This page synthesizes distributor stock, drop-in Skyworks and Silicon Labs family alternatives, and PCIe-specific design notes that complement the manufacturer datasheet.
SI53102-A3-GMR - 1:2 PCIe Gen4 Clock Buffer, 8-TDFN | Skyworks
The Skyworks Solutions SI53102-A3-GMR is a high-performance 1:2 PCI Express fan-out clock buffer that delivers two low-power, PCIe-compliant differential clock outputs from a single reference input. Housed in a compact 1.4 mm x 1.6 mm 8-pin TDFN-EP surface-mount package, the part operates at 100 MHz and is qualified to support PCIe Gen 1, Gen 2, Gen 3, and Gen 4 common-clock architectures as well as Serial-ATA (SATA) signalling. According to the Skyworks Si53102-A1/A2/A3 datasheet, the A3 silicon revision adds the Gen 4 compliance margin required by 16 GT/s PCIe links while remaining backward-compatible with Gen 1/2/3 endpoints. A 2.5 V or 3.3 V supply and integrated source-termination complete the feature set. A clock buffer is a timing-IC category that replicates a reference clock to multiple loads while preserving edge rate, phase noise, and additive jitter. Within the broader hierarchy, clock buffers sit under fan-out buffers, which fall under clock generators, which sit under clock and timing ICs. PCIe clock buffers in particular must meet the strict Refclk jitter budgets defined by the PCI-SIG CEM specification; the SI53102 family is engineered to add minimal jitter so the system-level budget is preserved even after fan-out to two downstream devices. Key features include PCIe Gen 1/2/3/4 compliance, two differential HCSL-compatible outputs, no requirement for external bias or termination resistors, integrated source-termination for 85-ohm differential traces, low additive Gen 4 jitter, and a spread-spectrum-tolerant input that allows pass-through of SSC-modulated reference clocks. The TDFN-8 EP package exposes a thermal pad that should be soldered to a continuous ground pour; this keeps junction temperature low across the industrial operating range and provides a low-inductance RF return path for the differential outputs. Architecture-wise, the SI53102 uses an internal PLL-less fan-out topology: the differential input is AC-coupled, internally biased, and re-driven through matched current-mode logic (CML) output stages. This avoids PLL lock time, SSC tracking concerns, and phase-transient glitches at the expense of bypassing any intentional frequency translation, meaning the outputs are always at the same frequency as the reference. The result is a deterministic, low-latency buffer suited to link-training and hot-plug events. Typical applications include PCIe riser cards, server backplanes, workstation motherboards, SATA storage controllers, and any embedded computing platform that needs to fan a 100 MHz HCSL reference clock to two downstream endpoints such as a root-complex PHY and an M.2 socket. When designing with this device, route the differential output pairs with 85-ohm differential impedance and provide a clean ground reference on the EP pad, because return-path discontinuities will convert into common-mode noise and degrade the PCIe Gen 4 eye margin. This page synthesizes distributor pricing, drop-in alternatives, and application guidance not aggregated on a single manufacturer or distributor page, making it easier to compare the SI53102-A3-GMR against its A1/A2 siblings and competing 1:2 PCIe buffers.
SI53112-A00AGM - 12-Output PCIe Gen 3 ZDB Buffer | Skyworks
The Skyworks Solutions (formerly Silicon Labs) SI53112-A00AGM is a 1:12 low-power, differential zero-delay buffer (ZDB) that meets the Intel DB1200ZL specification for distributing reference clocks. The device operates from a 100 MHz or 133.33 MHz differential input and provides twelve 100 MHz or 133.33 MHz differential output pairs (24 outputs total), making it optimized for Intel QuickPath Interconnect (QPI), PCIe Gen 1/2/3/4, SAS, SATA, and Intel Scalable Memory Interconnect (SMI) applications. It is packaged in a 64-pin QFN (9x9 mm) with an exposed pad. A zero-delay buffer (ZDB) is a clock-distribution IC whose internal PLL aligns the output edges to the reference input, achieving sub-100 ps input-to-output propagation delay. The ZDB category sits within the broader hierarchy of clock buffers -> clock timing ICs -> integrated circuits. ZDBs differ from conventional clock buffers in that they preserve phase coherence between input and output, which is mandatory for fan-out, synchronous, source-synchronous, and jitter-sensitive serial protocols where the reference clock must remain phase-locked to the system master. Key specifications include 12 differential output pairs (HCSL), a 25 MHz to 200 MHz output frequency range, < 0.5 ps RMS phase jitter (12 kHz-20 MHz) at 133.33 MHz, 50 ps input-to-output propagation delay, 3.3 V core supply, low additive jitter design, hardware frequency-select pin (100M_133M), and SMBus serial interface support for output enable and skew control. The silicon is built on a low-power CMOS process and integrates a wideband PLL with an internal VCO and on-chip termination. Typical applications include PCIe Gen 3/4 server backplanes, enterprise SSD storage arrays using SAS/SATA, Intel QPI reference-clock fan-out for multi-socket server platforms, and clock trees in workstation motherboards. The exposed thermal pad (EP) provides a low thermal-resistance path for the 64-QFN package, allowing reliable operation even when all 12 output pairs drive active lanes. A critical design consideration: HCSL outputs require an external series resistor (typically 33 ohms to 85 ohms) close to each output pin to set the HCSL swing and provide source termination; omitting this resistor violates PCIe electrical compliance. Decouple VDDA/VDD with 0.1 uF X7R ceramics adjacent to the device. This page synthesizes distributor pricing from Mouser/DigiKey/Octopart, parametric comparison with same-brand Skyworks PCIe ZDB variants, and practical design notes not consolidated on the manufacturer landing page.
SI5324C-C-GM - 945MHz Jitter Attenuator | Skyworks
The Skyworks SI5324C-C-GM is a precision clock multiplier and jitter attenuator that accepts two input clocks from 2 kHz to 710 MHz and generates two output clocks from 2 kHz to 945 MHz, with selected frequencies up to 1.4 GHz. It is packaged in a 36-QFN 6 x 6 mm package and is intended for timing applications requiring low phase noise and sub-1 ps jitter performance. The device supports programmable clock multiplication and frequency synthesis through I2C or SPI control, while its integrated loop filter provides selectable loop bandwidths from 4 Hz to 525 Hz. A clock multiplier, also called a frequency multiplier or PLL-based clock synthesizer, generates a stable output frequency from one or more reference clocks. A jitter attenuator adds phase-noise filtering and frequency-translation capabilities, making it part of the clock-and-timing IC hierarchy: clock multiplier -> jitter attenuator -> timing IC -> semiconductor. This is useful when a system must clean an existing clock, translate frequencies, or create multiple related outputs without relying on a simple fixed-ratio oscillator. Key verified features include two independent input-clock paths, two independently divided outputs from a common synthesis engine, programmable frequency translation, and ultra-low output jitter. Published output jitter can reach 290 fs rms from 12 kHz to 20 MHz and 320 fs rms from 50 kHz to 80 MHz. The low-loop-bandwidth architecture is suited to applications where accumulated upstream timing noise must be reduced before driving precision converters, communications equipment, or video circuitry. The SI5324 family uses DSPLL technology according to the manufacturer product description. Its external reference can also serve as a clock source for frequency synthesis. Configuration is software-controlled through I2C or SPI, allowing the device to be integrated into systems requiring programmable clocks, calibration, or multiple derived outputs. The exact input-output frequency combination and loop bandwidth depend on the programming configuration and must be validated against the manufacturer datasheet. Typical uses include Ethernet and WAN timing, SONET/SDH/STM systems, video clock generation, optical transport, test equipment, and high-speed communication links. The part is particularly suitable when a board receives a noisy reference but needs a low-jitter output with a different frequency. Compared with a basic buffer, it provides frequency synthesis and attenuation in one device; compared with a dedicated crystal oscillator, it supports programmable operating conditions. A key design consideration is clock-source quality and loop-bandwidth selection. The input clock, external reference, crystal or resonator network, output loads, and programming values must be designed together because incorrect loop settings can degrade jitter performance or prevent lock. Follow the manufacturer datasheet for the 36-QFN pin assignments, differential clock connections, exposed-pad treatment, decoupling, layout, and recommended external components. This page consolidates verified frequency-range, jitter, interface, package, and source information with application-oriented design guidance. It does not infer an unverified stock status, lifecycle statement, price, pinout, or drop-in replacement; those fields remain qualified where the supplied data does not establish them.
SI53306-B-GMR - 1:4 Universal Low-Jitter Clock Buffer | Skyworks
The Skyworks (formerly Silicon Labs) SI53306-B-GMR is a universal 1:4 low-jitter clock buffer and level translator housed in a 16-pin QFN with exposed pad, operating over an output frequency range of 1 MHz to 725 MHz. According to the manufacturer datasheet, the device delivers typical additive jitter of 50 fs RMS and supports pin-selectable output clock signal formats (LVPECL, LVDS, HCSL, LVCMOS) plus divider selection. It uses Skyworks' advanced CMOS technology with built-in LDOs for high PSRR, and provides a glitchless switching mux that makes it ideal for redundant clocking applications where two reference clocks must be switched without output disturbance. A clock buffer (also called a fanout buffer) is a timing IC that takes a single reference clock input and produces multiple phase-aligned copies to drive several downstream loads. Within the broader power/timing hierarchy, the Si53306 sits below clock generators (PLL/VCXO-based frequency synthesis) and below clock multipliers, but above simple gate-buffer fanout because it adds jitter-cleaning, level translation, and format conversion. By replicating a low-jitter reference across a backplane, a buffer minimizes skew between loads and prevents the reference from being loaded down by multiple receiver inputs. Key features of the SI53306-B-GMR include: 1:4 fanout from any single-ended or differential input, output frequency up to 725 MHz with 50 fs typical additive jitter, built-in LDOs providing high PSRR for noisy supply environments, pin-selectable output format on each bank (LVPECL, LVDS, HCSL, LVCMOS), an integrated glitchless 2:1 input mux for redundancy, and per-output divider options (1, 2, 4, 5, 8, 10, 20, 40, 80, 160). The wide supply range of 2.5 V or 3.3 V and 16-QFN exposed-pad package further simplify board layout by removing the need for an external LDO and improving thermal dissipation. Architecturally, the Si53306 is built on a low-noise CMOS process with on-die LDO regulators for each supply rail, an input-receiving stage that accepts differential or single-ended clocks, a glitchless 2:1 mux for redundant inputs, an output-format block per pair, and divider logic for clock-rate conversion. Additive jitter below 100 fs RMS (12 kHz–20 MHz) means the device does not appreciably degrade the reference phase noise budget, which is critical for 100G/400G Ethernet PHYs, FPGA SERDES, and ADC/DAC sample clocks. The exposed thermal pad lowers junction-to-PCB thermal resistance for continuous high-frequency operation. Typical applications for the SI53306-B-GMR include redundant clock distribution in telecom/networking line cards, FPGA and ASIC reference-clock fanout for data center switches, low-jitter ADC/DAC sampling-clock distribution in test and measurement instruments, OTN/optical-transport reference fanout, and broadcast video routing systems. The pin-selectable output formats allow the same BOM to serve boards that mix LVPECL transceivers, LVDS FPGAs, and LVCMOS ASICs. When designing with this device, place the device close to the receivers to minimize trace-induced skew, and use the exposed pad to provide a low-impedance ground return. The integrated LDOs tolerate noisy multi-rail supplies but still benefit from local 0.1 µF + 10 µF decoupling on each supply pin. This page synthesizes distributor pricing, drop-in Skyworks/TI/Renesas equivalents, and practical design notes not found in the manufacturer datasheet.