Texas Instruments SN74AVC1T45DCKRG4

Overview

SN74AVC1T45 from Texas Instruments is a single-bit dual-supply bus transceiver enabling bidirectional voltage-level translation between 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V domains with configurable VCCA/VCCB rails (1.2V–3.6V), ±12mA drive at 3.3V, 4.6V I/O tolerance, and 3-state outputs - deployed in low-voltage interconnects between SoCs and peripherals.

For engineers reviewing the SN74AVC1T45 datasheet, SN74AVC1T45 pinout, SN74AVC1T45 application, or SN74AVC1T45 equivalent, key selection criteria include dual-rail supply flexibility, VCC isolation behavior, Ioff partial-power-down support, high-speed translation capability up to 500Mbps, and NanoFree™ SOT-SC70 (DCK) package compatibility with space-constrained PCB layouts.

Technical Context

The SN74AVC1T45 implements a noninverting, direction-controlled bidirectional translation architecture where DIR input (referenced to VCCA) selects data flow: high enables A→B transmission, low enables B→A. Both A and B ports feature active input circuitry referenced to their respective supplies, requiring defined logic levels to avoid excess ICC/ICCZ.

VCC isolation ensures both ports enter high-impedance state if either VCCA or VCCB is at GND; Ioff functionality disables outputs during partial power-down to prevent backflow current. The device supports asynchronous communication across mixed-voltage buses without external biasing or level-shifting components.

Key Specifications

Pinout & Package

SN74AVC1T45 is packaged in the Texas Instruments NanoFree™ DCK (SOT-SC70, 6-pin) package measuring 2.0mm × 2.1mm - die-as-package construction minimizes parasitic inductance and footprint while supporting fine-pitch automated assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage translation applications.

Compared with TXB0101DGSR and SN74LVC1T45DBVR, SN74AVC1T45 uniquely delivers programmable bidirectional control, 500Mbps performance, and true dual-rail independence - making it the only option for high-speed, mixed-voltage, direction-gated applications requiring guaranteed timing and isolation.

Availability

SN74AVC1T45 is available at Aetrix Electronics and suitable for mobile processor interfacing, industrial sensor hubs, automotive infotainment displays, and enterprise SSD controller interfaces requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SN74AVC1T45 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 company designing analog ICs, embedded processors, and connectivity solutions for industrial, automotive, and consumer markets.

SN74AVC1T45 belongs to TI's AVC (Advanced Very-low-voltage CMOS) logic family, engineered specifically for ultra-low-voltage bidirectional level translation in space- and power-constrained portable and embedded systems.

FAQ

What is the function of the DIR pin on the SN74AVC1T45?

The DIR (direction) pin on the SN74AVC1T45 controls data flow direction and is referenced to VCCA. When DIR is high, data passes from the A port to the B port; when DIR is low, data flows from B to A. It has no internal pullup or pulldown, so an external bias is required to ensure a defined logic state during power-up or idle periods. This explicit control eliminates bus contention risks inherent in auto-sensing translators.

Can SN74AVC1T45 operate with VCCA = 1.2V and VCCB = 3.3V?

Yes, SN74AVC1T45 is fully specified for simultaneous operation with VCCA = 1.2V and VCCB = 3.3V. In this configuration, it achieves up to 320Mbps translation speed with typical propagation delay of 3.4ns (A→B) and maintains 4.6V I/O tolerance on the B port. The device's dual-rail architecture guarantees correct VIH/VIL thresholds and output drive strength across this voltage combination without external components.

Does SN74AVC1T45 support partial power-down mode?

Yes, SN74AVC1T45 supports partial power-down via its Ioff feature. When either VCCA or VCCB is at 0V, the corresponding I/O port is disabled, preventing current backflow into the powered-down supply domain. This behavior is characterized across –40°C to +85°C and ensures system-level safety during staggered power sequencing - a critical requirement in battery-powered and hot-plug applications.

What package type does SN74AVC1T45DCKRG4 use?

SN74AVC1T45DCKRG4 uses the DCK package - a 6-pin SOT-SC70 variant measuring 2.0mm × 2.1mm - part of Texas Instruments' NanoFree™ technology where the silicon die serves as the package. This eliminates bond wires and mold compound, reducing parasitic inductance and thermal resistance (RθJA = 211.4°C/W), and enables finer pitch assembly than standard SOT-23.

How does VCC isolation work on SN74AVC1T45?

VCC isolation on SN74AVC1T45 ensures that if either VCCA or VCCB is driven to GND (e.g., during power-down or fault), both A and B ports automatically enter a high-impedance state. This prevents unintended current paths, avoids bus contention, and protects downstream devices. The feature is intrinsic to the silicon design and requires no external circuitry - verified per JESD78 Class II latch-up testing (>100mA).