Texas Instruments 74AVCH1T45DCKRE4

Overview

74AVCH1T45DCKRE4 from Texas Instruments is a single-bit, dual-supply noninverting bus transceiver with configurable level-shifting between 1.2V–3.6V rails on both A and B ports, 3-state outputs, bus-hold circuitry, and I_off support for partial-power-down operation. It enables bidirectional voltage translation in low-pin-count interfaces such as I²C pull-up domain bridging or FPGA-to-ASIC I/O interfacing.

For engineers reviewing the 74AVCH1T45DCKRE4 datasheet, 74AVCH1T45DCKRE4 pinout, 74AVCH1T45DCKRE4 application, or 74AVCH1T45DCKRE4 equivalent, key selection criteria include VCCA/VCCB supply independence, DIR-referenced-to-VCCA control logic, 4.6V I/O tolerance, bus-hold elimination of external resistors, and verified 500Mbps data rate at 1.8V→3.3V translation.

Technical Context

The device implements a fully configurable dual-rail architecture where A-port signals (including DIR) are referenced to VCCA (1.2V–3.6V), and B-port signals are referenced to VCCB (1.2V–3.6V). This allows asynchronous bidirectional translation across any combination of 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V domains without direction-control voltage translation.

Its bus-hold circuitry actively sustains undriven inputs at valid logic states-IBHL ≥25μA at VCCA=1.2V, IBHH ≥100μA at VCCA=3.3V-eliminating need for external biasing. VCC isolation forces outputs into high-impedance if either VCCA or VCCB = GND, while I_off limits leakage to ±5μA when either supply is powered down.

Key Specifications

Pinout & Package

74AVCH1T45DCKRE4 is packaged in the SC70-6 (DCK) package, measuring 2.00mm × 1.25mm, with 0.65mm pitch and bottom-side thermal pad. The NanoStar™ footprint supports ultra-dense PCB layouts in space-constrained portable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1T45DBVR and TXS0101DCKR, the 74AVCH1T45DCKRE4 uniquely delivers true dual-supply independence, bus-hold integration, and 500Mbps performance - making it optimal for high-density, multi-rail embedded designs requiring minimal external components and strict timing control.

Availability

74AVCH1T45DCKRE4 is available at Aetrix Electronics and suitable for mobile sensor hubs, FPGA-to-MCU bridges, and low-power IoT node designs requiring stable component supply, long-term lifecycle support, and consistent SC70-6 packaging.

Supply support for 74AVCH1T45DCKRE4 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies, with decades of innovation in logic, interface, and power management ICs.

The SN74AVCH1T45 belongs to TI's AVC logic family, designed specifically for ultra-low-voltage, high-speed bidirectional level translation in space- and power-constrained portable and industrial electronics.

FAQ

What voltage ranges does the 74AVCH1T45DCKRE4 support on its VCCA and VCCB supplies?

The 74AVCH1T45DCKRE4 supports independent supply voltages from 1.2V to 3.6V on both VCCA and VCCB pins. This allows translation between any pair of standard low-voltage domains-including 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V-without external components. The DIR input is referenced solely to VCCA, eliminating need for direction-control level shifting.

Does the 74AVCH1T45DCKRE4 require external pullup or pulldown resistors on its A or B ports?

No. The 74AVCH1T45DCKRE4 integrates active bus-hold circuitry on both A and B ports, which sustains undriven inputs at valid logic states. At VCCA = 3.3V, bus-hold provides ±100μA sustaining current-sufficient to maintain stable logic levels without external resistors, reducing BOM count and PCB area.

How does the 74AVCH1T45DCKRE4 behave when one supply rail is powered down?

When either VCCA or VCCB is at GND, the 74AVCH1T45DCKRE4 activates VCC isolation: all outputs enter high-impedance state. Simultaneously, I_off circuitry limits leakage current to ±5μA maximum, preventing damaging backflow. Bus-hold remains active on the powered-up side, preserving signal integrity during asymmetric power sequencing.

What is the maximum data rate supported by the 74AVCH1T45DCKRE4, and under what conditions?

The 74AVCH1T45DCKRE4 achieves up to 500Mbps when translating from 1.8V to 3.3V. Other validated rates include 320Mbps (<1.8V→3.3V), 280Mbps (→1.5V), and 240Mbps (→1.2V). These values are measured under specified load and transition conditions per TI's characterization methodology and reflect real-world timing margins for short-trace PCB interconnects.

Is the 74AVCH1T45DCKRE4 compatible with 5V-tolerant systems?

Yes. All I/O pins (A, B, and DIR) are rated for 4.6V absolute maximum input voltage, enabling safe interfacing with 5V peripherals without external clamping diodes or series resistors. This tolerance applies regardless of VCCA or VCCB supply level-making the 74AVCH1T45DCKRE4 suitable for mixed-voltage systems with legacy 5V components.