STMicroelectronics 74VCXH16245TTR

Overview

74VCXH16245TTR from STMicroelectronics is a low-voltage CMOS 16-bit bus transceiver (3-state) with bidirectional data flow controlled by DIR inputs, 3.6V-tolerant I/O, 2.5 ns max propagation delay at 3.0–3.6 V, ±24 mA output drive, and bus-hold on all data terminals - used in voltage-translating memory/data bus interfaces between 2.3V and 3.6V domains.

For engineers reviewing the 74VCXH16245TTR datasheet, 74VCXH16245TTR pinout, 74VCXH16245TTR application, or 74VCXH16245TTR equivalent, key selection criteria include 3.6V I/O tolerance, dual enable (nG) isolation control, symmetrical drive strength, bus-hold elimination of external biasing, and TSSOP-48 thermal and routing constraints.

Technical Context

This transceiver implements two independent 8-bit bidirectional data paths (A↔B), each with dedicated directional control (DIR) and output-enable (nG) inputs. Data direction is asynchronous and determined solely by DIR logic level, while nG asserts high-impedance state on both sides simultaneously.

It features bus-hold circuitry on all A- and B-side data pins to maintain last-valid logic state during high-Z, eliminating need for external pull resistors. Input/output protection includes 2 kV HBM ESD rating and latch-up immunity exceeding 300 mA per JESD17.

Key Specifications

Pinout & Package

TSSOP-48 package (4.4 mm × 12.5 mm body, 0.5 mm pitch), thermally enhanced for high-density PCB layouts; JEDEC MO-153 compliant with exposed pad not present.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC16245ADGGR and 74ALVC16245PW, the 74VCXH16245TTR uniquely combines 3.6 V I/O tolerance, integrated bus-hold, and power-down protection - making it optimal for mixed-voltage industrial and automotive subsystems requiring robustness and component count reduction.

Availability

74VCXH16245TTR is available at Aetrix Electronics and suitable for memory subsystem interfaces, FPGA-to-ASIC bridges, and industrial PLC backplanes requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for 74VCXH16245TTR 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 headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power management solutions with broad analog, digital, and mixed-signal portfolios.

The VCXH series targets low-voltage, high-speed logic applications requiring voltage translation, bus isolation, and robust I/O protection - designed specifically for next-generation portable, industrial, and automotive electronics.

FAQ

Can 74VCXH16245TTR operate with VCC = 1.8 V while interfacing to 3.6 V signals?

Yes. The device guarantees 3.6 V tolerance on all inputs and outputs across its full 1.8 V to 3.6 V VCC range. At 1.8 V supply, inputs recognize VIH ≥ 1.2 V and VIL ≤ 0.6 V, and outputs drive to VOH ≥ 1.6 V and VOL ≤ 0.45 V under 12 mA load - sufficient for reliable interfacing with 3.6 V CMOS logic.

What happens to bus-hold behavior when VCC = 0 V?

Bus-hold remains active only when VCC ≥ 0.8 V. Below that threshold, hold current drops below specification and external biasing is required. The device includes power-down protection: inputs and outputs enter high-impedance with <10 µA leakage (Ioff), preventing back-powering of the supply rail.

Is the 74VCXH16245TTR pin-compatible with standard 74HCT16245?

No. While functionally similar, the 74VCXH16245TTR uses a 48-pin TSSOP package with different pin mapping - e.g., DIR and nG signals are assigned to pins 1/24/25/48, whereas 74HCT16245 uses 48-pin SSOP with distinct layout. Direct replacement requires PCB redesign and signal routing verification.

How does output skew impact 16-bit parallel bus timing?

Maximum output-to-output skew is 0.5 ns across all 16 bits at VCC = 3.0–3.6 V. This ensures data valid window remains ≥ 95% of clock period for 200 MHz bus clocks, preventing setup/hold violations in synchronous interfaces like memory controllers or video data lanes.