Diodes Incorporated PI74ALVCH16501A

Overview

PI74ALVCH16501A from Pericom Semiconductor is an 18-bit universal bus transceiver with 3-state outputs, designed for bidirectional data flow between A- and B-buses in low-voltage systems. It operates from 2.3V to 3.6V V_CC, supports transparent/latched modes via LEAB/LEBA and CLKAB/CLKBA, and features active bus-hold on all I/Os. Used in industrial backplane interfaces requiring voltage-level flexible, noise-immune data bridging.

For engineers reviewing the PI74ALVCH16501A datasheet, PI74ALVCH16501A pinout, PI74ALVCH16501A application, or PI74ALVCH16501A equivalent, key selection criteria include dual-direction latch control timing, bus-hold retention without external resistors, 3.3V-compatible 18-bit I/O drive, and TSSOP-48 packaging for high-density PCB layouts.

Technical Context

This device implements two independent 18-bit transceiver paths (A↔B) with separate control logic per direction: OEAB/LEAB/CLKAB govern A-to-B flow, while OEBA/LEBA/CLKBA manage B-to-A flow. The Output Enables are complementary-OEAB is active-HIGH, OEBA is active-LOW-requiring pull-down on OEAB and pull-up on OEBA for safe power-up high-impedance state.

Each I/O incorporates hysteresis and bus-hold circuitry, eliminating need for external termination. Latching occurs on CLKAB's low-to-high transition when LEAB is LOW; transparent mode activates when LEAB is HIGH. Timing parameters are specified at V_CC = 3.3V ±10%, CL = 50pF, RL = 500Ω.

Key Specifications

Pinout & Package

PI74ALVCH16501A is packaged in a 48-pin plastic TSSOP (240 mil width), pin-compatible with industry-standard 48-TSSOP footprints. Thermal pad is not present; standard reflow profiles apply.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar universal bus transceiver applications.

Compared with SN74ALVTH16501 and 74LVC16501, PI74ALVCH16501A delivers superior noise immunity via hysteresis, eliminates 36 external resistors via bus-hold, and achieves 30% faster typical propagation-critical for deterministic timing in industrial control loops.

Availability

PI74ALVCH16501A is available at Aetrix Electronics and suitable for industrial backplane interfaces, FPGA-to-ASIC bridging, and modular instrumentation chassis requiring stable component supply, long-lifecycle support, and guaranteed RoHS-compliant manufacturing.

Supply support for PI74ALVCH16501A 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 was a fabless provider of high-performance interface and timing solutions, acquired by Diodes Incorporated in 2016; legacy Pericom logic remains widely deployed in industrial and telecom infrastructure.

The PI74ALVCH series targets low-voltage, high-speed digital interfacing in space-constrained industrial systems-emphasizing noise resilience, power-up safety, and minimal external component count.

FAQ

What is the recommended power-up sequence for PI74ALVCH16501A?

OEAB must be held LOW (via pulldown to GND) and OEBA held HIGH (via pullup to V_CC) during power ramp to ensure all outputs remain in high-impedance state until firmware initializes control signals. This prevents bus contention on powered-down systems. Minimum resistor values are determined by driver sink/source capability-typically 10kΩ suffices.

Does PI74ALVCH16501A support hot-swap operation?

Yes-bus-hold circuitry actively retains the last valid logic state on all A1–A18 and B1–B18 pins during insertion/removal, preventing floating inputs from causing undefined system behavior. However, V_CC sequencing must still follow manufacturer-recommended ramp rates (≤10V/ms) to avoid latch-up.

Can PI74ALVCH16501A operate at 2.5V V_CC with full timing guarantees?

Yes-data sheet specifies full AC/DC performance across 2.3V–3.6V, including propagation delay, setup/hold times, and drive strength. At 2.5V, t_PD increases to typ. 6.2ns (A→B), remaining within 100MHz timing budgets when loaded with ≤50pF.

How does the bus-hold feature interact with external pull-up/down resistors?

Bus-hold overrides external resistors weaker than ±54µA-so 10kΩ pull-ups at 3.3V (330µA) will dominate and disable bus-hold. To retain bus-hold functionality, omit external terminations entirely or use ≥100kΩ resistors. Internal hysteresis remains active regardless.