STMicroelectronics 74VCX1632245LB

Overview

74VCX1632245LB from STMicroelectronics is a dual-supply 16-bit bus transceiver with level translation capability, designed for bidirectional asynchronous communication between 3.3V/2.5V/1.8V buses. It features symmetrical output drive (8mA min at VCCA=3.0V/VCCB=1.65V), 4.4ns max propagation delay at TA=85°C, and integrated 26Ω series resistors on A-side outputs for EMI suppression in high-speed digital interfaces.

For engineers reviewing the 74VCX1632245LB datasheet, 74VCX1632245LB pinout, 74VCX1632245LB application, or 74VCX1632245LB equivalent, this device supports mixed-voltage system interconnects including 3.3V↔2.5V, 3.3V↔1.8V, and 2.5V↔1.8V translation with data rates up to 380 Mbps, while providing power-down protection and latch-up immunity exceeding 500mA per JESD17.

Technical Context

This IC implements two independent 8-bit transceivers (1A/1B and 2A/2B) with separate directional control (nDIR) and output enable (nG) inputs per side. Each transceiver supports true bidirectional data flow controlled by DIR signals, with high-impedance isolation when nG is asserted.

It operates across asymmetric supply rails: VCCA (2.3–3.6V) powers A-side I/Os and logic, while VCCB (1.65–2.7V) powers B-side I/Os. Input thresholds scale with respective VCC rails-VIHA/VILA referenced to VCCA, VIHB/VILB to VCCB-enabling robust voltage-level translation without external biasing.

Key Specifications

Pinout & Package

74VCX1632245LB is packaged in TFBGA54 (5.4mm × 5.4mm, 0.5mm pitch), with 54 terminals including 32 I/O pins (16 A-side, 16 B-side), 4 power/ground pins (2×VCCA, 2×VCCB, 4×GND), 4 control inputs (2×nDIR, 2×nG), and 4 NC pins.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-supply bus transceiver applications.

Compared with SN74AVC16T245RJR and TXB0108PWR, the 74VCX1632245LB uniquely combines integrated A-side termination, explicit DIR control for deterministic timing, and guaranteed 380 Mbps operation - making it optimal for DDR memory bridges and FPGA-ASIC interconnects requiring precise skew control and minimal layout overhead.

Availability

74VCX1632245LB is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive infotainment gateways, and FPGA-to-memory interface designs requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74VCX1632245LB 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

STMicroelectronics is a global semiconductor leader specializing in automotive, industrial, and power management ICs, with over 45 years of analog/mixed-signal design expertise and ISO/TS 16949-certified manufacturing.

The VCX family targets low-voltage, high-speed logic interfacing - specifically engineered for voltage translation in mixed-supply digital systems where power efficiency, timing precision, and ESD robustness are critical.

FAQ

What is the maximum supported data rate for 3.3V-to-1.8V translation?

The 74VCX1632245LB supports up to 380 Mbps when translating between 1.8V and 3.3V buses, verified under load conditions of CL = 30 pF and RL = 500 Ω at TA = 25°C. This performance is sustained across the full operating temperature range (−40°C to +85°C) with VCCA = 3.3V ±0.3V and VCCB = 1.8V ±0.15V, meeting timing requirements for LPDDR2 command/address channels.

Can VCCA and VCCB be powered from the same supply rail?

Yes - VCCA and VCCB may share a common 2.5V or 3.3V supply, but doing so eliminates level translation functionality and reduces the device to a standard 16-bit bus transceiver. The internal logic remains functional, and all DC specifications (e.g., IOHA/IOLA = 8mA min) still apply, though the 26Ω series resistors remain active only on A-side outputs.

How does the power-down protection work during VCCB loss?

When VCCB drops below 0.8V while VCCA remains active, the B-side inputs and outputs enter a high-impedance state with leakage current limited to ±10 µA (per IOZB spec). This prevents current backflow into unpowered B-side circuitry, protecting downstream 1.8V devices from damage or unintended activation during partial power sequencing.

Is the TFBGA54 package RoHS-compliant and lead-free?

Yes - the 74VCX1632245LB in TFBGA54 packaging complies with RoHS Directive 2011/65/EU and is fully lead-free, with matte tin surface finish on solder balls and halogen-free molding compound. The package meets JEDEC J-STD-020D moisture sensitivity level 3 (MSL3) and supports standard Pb-free reflow profiles up to 260°C peak temperature.