Diodes Incorporated PI74LVC3245ALE

Overview

PI74LVC3245ALE from Pericom Semiconductor is an 8-bit non-inverting bidirectional bus transceiver with dual-supply operation (VCCA = 2.7–3.6 V, VCCB = 4.5–5.5 V), enabling level translation between 3.3 V and 5 V buses. It features independent 3-state control via OE (active-low) and direction control via DIR, supporting asynchronous two-way data flow in mixed-voltage systems such as industrial I/O expansion and legacy peripheral interfacing.

For engineers reviewing the PI74LVC3245ALE datasheet, PI74LVC3245ALE pinout, PI74LVC3245ALE application, or PI74LVC3245ALE equivalent, key selection criteria include dual-rail voltage tolerance, propagation delay ≤6.3 ns (A→B), 3-state leakage ≤±5 µA, and industrial temperature support (–40°C to +85°C).

Technical Context

This transceiver implements a CMOS-based dual-supply architecture where A-port I/Os are referenced to VCCA (3.3 V domain) and B-port I/Os to VCCB (5 V domain), with internal level-shifting circuitry ensuring TTL-compatible inputs on both sides. Control logic (DIR, OE) is referenced to VCCA, enabling robust interface coordination when VCCA powers the system controller.

Propagation delays are asymmetrically optimized: tPHL/tPLH from A→B range 1.0–6.3 ns, while B→A delays are slightly faster (1.0–5.7 ns). Output enable timing (tPZL/tPLZ ≤7.8 ns) ensures rapid bus isolation during state transitions, critical for hot-swap-capable backplane designs.

Key Specifications

Pinout & Package

PI74LVC3245ALE is packaged in a Pb-free, green 24-pin TSSOP (173-mil wide, package code L), with 0.65 mm lead pitch and JEDEC MO-153F/AD compliance. The body dimensions are 7.7 mm × 4.3 mm × 1.2 mm (L × W × H), optimized for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC8T245RHLR and TXB0108PWR, PI74LVC3245ALE provides explicit DIR/OE control, true dual-rail independence, and lower 3-state leakage - making it the only choice for industrial backplane designs requiring guaranteed bus isolation and mixed-voltage protocol compliance.

Availability

PI74LVC3245ALE is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, embedded system peripheral bridging, and automotive body control module designs requiring stable component supply and long-term lifecycle support.

Supply support for PI74LVC3245ALE 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 interface, timing, and signal-integrity solutions for industrial, communications, and computing markets.

The PI74LVC3245A belongs to Pericom's LVC-series bidirectional transceivers, designed specifically for robust voltage-level translation in mixed-signal industrial control systems with stringent ESD and latch-up immunity requirements.

FAQ

Can PI74LVC3245ALE operate with VCCA = 3.3 V and VCCB = 5.0 V simultaneously?

Yes. The device is explicitly characterized for VCCA = 3.3 V (typical) and VCCB = 5.0 V (typical), with full DC and AC specifications guaranteed across the overlapping operating ranges: VCCA = 2.7–3.6 V and VCCB = 4.5–5.5 V. This dual-rail configuration enables seamless 3.3 V ↔ 5 V translation without external components.

What happens if OE is held HIGH while DIR is toggled?

When OE is HIGH, both A and B ports are forced into high-impedance (3-state) regardless of DIR state. Data flow is completely disabled - no signal passes in either direction. DIR transitions have no effect until OE is pulled LOW to re-enable the transceiver.

Is the NC pin (Pin 21) required to be grounded?

No. Pin 21 is internally unconnected and must remain floating or optionally tied to GND for mechanical stability. Pericom's packaging documentation confirms no internal bond wire or die connection exists; grounding it introduces no functional benefit but may aid solder paste retention during reflow.

Does PI74LVC3245ALE support hot-swap insertion into a live 5 V bus?

It supports controlled hot-swap operation when powered sequencing guidelines are followed: GND connected first, VCCA ramped before VCCB, and OE ramped with or ahead of VCCA. The absolute maximum rating of –0.5 V to +7 V on VCCB and I/O clamp current of –50 mA provide margin against transient overvoltage during insertion.