Texas Instruments SN74AVC20T245ZQLR

Overview

SN74AVC20T245ZQLR from Texas Instruments is a 20-bit dual-rail noninverting bus transceiver enabling bidirectional voltage-level translation between 1.2-V to 3.6-V domains. It features independent VCCA and VCCB rails, I_off partial-power-down support, VCC isolation, and 4.6-V tolerant I/Os. Used in mixed-voltage SoC interconnects, FPGA-to-ASIC data buses, and low-power portable memory interfaces.

For engineers reviewing the SN74AVC20T245ZQLR datasheet, SN74AVC20T245ZQLR pinout, SN74AVC20T245ZQLR application, or SN74AVC20T245ZQLR equivalent, key selection criteria include dual-supply rail flexibility, 380 Mbps max data rate (1.8-V ↔ 3.3-V), ±50 mA output drive, latch-up immunity (>100 mA), and Pb-free VFBGA-56 (ZQL) packaging for high-density PCB layouts.

Technical Context

This device implements two independent 10-bit transceiver sections (1A↔1B and 2A↔2B), each with dedicated DIR and OE controls referenced to VCCA. Directional data flow is determined by logic level on DIR inputs, while OE enables/disables outputs into high-impedance state. The VCC isolation feature forces both ports into Hi-Z if either VCCA or VCCB is at GND.

I_off protection disables outputs during power-down to prevent backflow current, and overvoltage-tolerant I/Os allow safe operation when interfacing with higher-voltage systems. Control inputs (DIR, OE) are referenced to VCCA, ensuring consistent switching thresholds across supply combinations.

Key Specifications

Pinout & Package

VFBGA-56 package (ZQL), 5.5 mm × 3.5 mm, 0.5-mm pitch, bottom-side ball array, Pb-free finish, MSL Level 3 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74AVC20T245ZQLR, SN74AVCH16T245DGGR offers identical dual-rail behavior in smaller footprint but halves channel count and removes VFBGA packaging; TXB0108PWR simplifies direction control but sacrifices deterministic bidirectional timing, isolation, and scalability needed for 20-bit parallel interfaces.

Availability

SN74AVC20T245ZQLR is available at Aetrix Electronics and suitable for mobile processor interconnects, FPGA-to-ASIC bridges, industrial PLC backplanes, and automotive infotainment SoC expansions requiring stable component supply, long-term lifecycle assurance, and Pb-free compliance.

Supply support for SN74AVC20T245ZQLR 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 solutions with over 90 years of innovation in high-reliability electronics.

The SN74AVC20T245ZQLR belongs to TI's AVC (Advanced Very-low-voltage CMOS) logic family, designed specifically for ultra-low-voltage, high-speed bidirectional translation in battery-powered and thermally constrained systems.

FAQ

What is the minimum operating voltage for SN74AVC20T245ZQLR?

The SN74AVC20T245ZQLR operates with VCCA and VCCB independently down to 1.2 V. Its guaranteed functionality starts at 1.2 V per rail, and it remains fully specified across the full 1.2-V to 3.6-V range - making it ideal for modern low-power SoCs and energy-harvesting systems where supply headroom is limited.

Does SN74AVC20T245ZQLR support hot-swap or partial-power-down operation?

Yes, SN74AVC20T245ZQLR supports partial-power-down via its I_off circuitry: when either VCCA or VCCB is at 0 V, outputs are disabled with leakage current limited to ±1 µA, preventing damaging backflow. This enables safe hot-plug operation in modular systems like PLC backplanes and server mezzanine cards.

Can SN74AVC20T245ZQLR translate between 1.2 V and 3.3 V simultaneously?

Yes, SN74AVC20T245ZQLR is explicitly designed for this use case: set VCCA = 1.2 V and VCCB = 3.3 V to translate data from a 1.2-V processor core to a 3.3-V peripheral. The device achieves up to 100 Mbps in this configuration, with all I/Os remaining 4.6-V tolerant to handle overshoot and noise margins safely.

What is the thermal performance of the ZQL package in SN74AVC20T245ZQLR?

The SN74AVC20T245ZQLR in VFBGA-56 (ZQL) package has a thermal impedance θ_JA of 42°C/W under standard JEDEC conditions. This enables reliable operation at full speed in compact, sealed enclosures - such as automotive head units or handheld medical devices - without requiring forced airflow or heatsinks.

How does the VCC isolation feature work in SN74AVC20T245ZQLR?

In SN74AVC20T245ZQLR, the VCC isolation feature ensures that if either VCCA or VCCB drops to GND, both A and B ports automatically enter high-impedance state - regardless of DIR or OE states. This prevents bus contention during asymmetric power sequencing, a critical safeguard in multi-rail systems like industrial controllers and battery-backed memory modules.