Diodes Incorporated PI49FCT20802QEX

Overview

PI49FCT20802QEX from Pericom Semiconductor is a 2.5V, non-inverting 1:5 clock buffer optimized for high-frequency, low-skew clock distribution in networking systems. It delivers five synchronized LVCMOS outputs from a single input, with output-to-output skew ≤150ps, propagation delay ≤2.7ns at 150MHz, and operates across –40°C to +85°C. It supports 3V-tolerant inputs and features multiple VDD/GND pins for noise suppression in synchronous Ethernet switch timing paths.

For engineers reviewing the PI49FCT20802QEX datasheet, PI49FCT20802QEX pinout, PI49FCT20802QEX application, or PI49FCT20802QEX equivalent, key selection criteria include output count (5), skew budget (<150ps), supply voltage (2.5V ±0.2V), industrial temperature range, and QSOP-16 packaging compatibility with legacy FCT logic footprints.

Technical Context

The PI49FCT20802QEX implements a high-speed, low-noise buffered fanout architecture with dedicated power/ground pin pairs per output group to minimize simultaneous switching noise. Its internal design enforces matched trace lengths and balanced drive strength across all five CLKx outputs, enabling deterministic skew control under 150MHz operation with 12pF–22pF capacitive loads.

It uses TTL-compatible input thresholds (VIH ≥1.7V, VIL ≤0.7V) with 3V tolerance, allowing direct interfacing to 3.3V clock sources without level shifters. The device draws ≤136mA dynamic current at 150MHz with 15pF/33Ω load, and quiescent current remains below 20μA - critical for power-constrained telecom line cards.

Key Specifications

Pinout & Package

PI49FCT20802QEX is packaged in a Pb-free, RoHS-compliant 16-pin QSOP (Package Code Q), 150-mil wide, with 0.635mm lead pitch. Pin layout follows JEDEC MO-137B/AB standard and is pin-compatible with industry-standard 16-pin QSOP clock buffers.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar clock buffer applications.

Compared with IDT 5PB1102PGI and ON Semi NB3N511MNR2G, PI49FCT20802QEX offers optimal balance of 5-output fanout, 3V-tolerant input flexibility, and ultra-low skew in a cost-effective QSOP package - making it preferred for space-constrained, single-ended clock distribution in telecom edge devices.

Availability

PI49FCT20802QEX is available at Aetrix Electronics and suitable for Ethernet switch timing, optical transport line cards, baseband unit backplanes, and industrial PLC controllers requiring stable component supply and long-term lifecycle support.

Supply support for PI49FCT20802QEX includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Pericom Semiconductor (acquired by Diodes Incorporated in 2016) specialized in high-performance timing, interface, and signal-integrity solutions for communications and computing infrastructure.

The PI49FCT20802 belongs to Pericom's FCT-series clock buffer family, engineered specifically for low-skew, low-jitter clock distribution in carrier-grade networking and telecom equipment operating at 100MHz–150MHz.

FAQ

Is PI49FCT20802QEX pin-compatible with PI49FCT20802LE?

Yes - both share identical 16-pin QSOP (Q) and TSSOP (L) footprints and pin functions. The 'Q' and 'L' suffixes denote package type only; electrical behavior, timing specs, and pin mapping are fully identical across both variants.

What is the maximum capacitive load supported per output?

The device is characterized for 12pF–22pF loads per output. At 150MHz with 12pF load, tPD is 2.4–2.7ns and tSK(o) is ≤150ps. Loads exceeding 25pF may increase skew and degrade rise/fall times beyond spec limits.

Does PI49FCT20802QEX require external bypass capacitors?

Yes - Pericom recommends 0.1μF ceramic capacitors placed as close as possible to each VDD pin (pins 1, 7, 13, 16), with additional bulk capacitance (e.g., 4.7μF) near the device. This is mandatory to maintain <150ps skew and suppress supply-induced jitter.

Can PI49FCT20802QEX drive unterminated transmission lines?

No - its outputs are designed for controlled-impedance, properly terminated lines (e.g., 33Ω series or 50Ω parallel). Driving unterminated lines causes reflections that increase jitter, skew, and duty cycle distortion beyond guaranteed limits.