Texas Instruments SN74LVCH16T245DL

Overview

SN74LVCH16T245 from Texas Instruments is a 16-bit dual-supply noninverting bus transceiver enabling bidirectional voltage-level translation between 1.65 V–5.5 V domains. It features two independent supply rails (VCCA and VCCB), configurable direction control (1DIR/2DIR), tri-state output enable (1OE/2OE), and bus-hold on all data I/Os. It is used in mixed-voltage system interconnects such as 1.8-V microcontrollers interfacing 3.3-V peripherals.

For engineers reviewing the SN74LVCH16T245 datasheet, SN74LVCH16T245 pinout, SN74LVCH16T245 application, or SN74LVCH16T245 equivalent, key selection criteria include dual-rail voltage flexibility, Ioff partial-power-down support, VCC isolation behavior, bus-hold elimination of external resistors, and guaranteed 16-bit channel synchronization under asymmetric supply conditions.

Technical Context

The SN74LVCH16T245 implements a fully independent dual-rail architecture: A-port I/Os and control inputs (1DIR, 2DIR, 1OE, 2OE) are referenced to VCCA (1.65–5.5 V), while B-port I/Os are referenced to VCCB (1.65–5.5 V). Direction and output-enable logic operate exclusively on VCCA, ensuring deterministic control even during VCCB power sequencing.

Each of its two 8-bit transceiver sections operates autonomously: DIR determines data flow direction (A→B or B→A), OE places both ports into high-impedance state, and bus-hold circuitry actively maintains valid logic levels on undriven A/B inputs without external components. The VCC isolation feature forces all outputs into high-Z if either VCCA or VCCB is at GND.

Key Specifications

Pinout & Package

SN74LVCH16T245 is available in SSOP-48 (DL package), with body size 15.88 mm × 7.49 mm. Pinout follows standard TSSOP/SSOP numbering (1–48), with dual 8-bit I/O groups, dedicated DIR/OE controls per section, and separate VCCA/VCCB/GND terminals.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TXB0108PWR and SN74AVCH16T245DGGR, the SN74LVCH16T245 provides deterministic manual direction control, higher output drive (±32 mA), and broader voltage compatibility (1.65–5.5 V on both rails), making it optimal for industrial parallel bus translation where timing predictability and robustness outweigh ultra-low power or auto-sensing needs.

Availability

SN74LVCH16T245 is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive ADAS sensor hubs, enterprise SSD controllers, and medical imaging data acquisition systems requiring stable component supply, long-term lifecycle support, and guaranteed dual-rail interoperability.

Supply support for SN74LVCH16T245 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 delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and personal electronics markets.

The SN74LVCH16T245 belongs to TI's LVCMOS family of level translators, engineered specifically for robust, high-fidelity voltage-domain bridging in mixed-supply systems where power sequencing, bus stability, and ESD resilience are critical.

FAQ

What voltage ranges does the SN74LVCH16T245 support on its A and B ports?

The SN74LVCH16T245 supports 1.65 V to 5.5 V on both VCCA (A port and control inputs) and VCCB (B port). This allows translation between any combination of 1.8-V, 2.5-V, 3.3-V, and 5-V logic domains. The control inputs (1DIR, 2DIR, 1OE, 2OE) are always referenced to VCCA, so their VIH/VIL thresholds scale with VCCA - not VCCB.

How does the VCC isolation feature work in the SN74LVCH16T245?

The VCC isolation feature in the SN74LVCH16T245 ensures that if either VCCA or VCCB is driven to GND (0 V), all outputs on both A and B ports enter a high-impedance state. This prevents false logic signals from propagating across the bus during power-up, power-down, or fault conditions. It is implemented at the silicon level and requires no external circuitry - a key safety mechanism for hot-pluggable systems.

Can the SN74LVCH16T245 operate with VCCA = 3.3 V and VCCB = 1.8 V simultaneously?

Yes, the SN74LVCH16T245 is explicitly designed for asymmetric dual-rail operation. With VCCA = 3.3 V and VCCB = 1.8 V, the A-port I/Os and control inputs operate at 3.3 V logic levels, while the B-port I/Os translate to and from 1.8 V. Propagation delay remains within specification (e.g., tPLH ≤ 6.2 ns A→B), and bus-hold functionality remains active on both sides.

Does the SN74LVCH16T245 require external pullup or pulldown resistors on its data lines?

No. The SN74LVCH16T245 integrates active bus-hold circuitry on all 16 data I/Os (1A1–1A8, 1B1–1B8, 2A1–2A8, 2B1–2B8), which maintains undriven inputs at valid logic HIGH or LOW states. TI explicitly advises against using external pull resistors with bus-hold enabled, as they may interfere with the internal sustaining current (IBHL/IBHH) and increase power consumption.

What is the maximum data rate supported by the SN74LVCH16T245?

The SN74LVCH16T245 supports data rates up to approximately 200 MHz under typical conditions (e.g., VCCA = 3.3 V, VCCB = 5 V, CL = 15 pF), derived from its worst-case propagation delay of 6.0 ns (tPHL B→A). Actual achievable rate depends on load capacitance, supply voltages, and PCB layout; for 1.8-V ↔ 3.3-V translation, maximum frequency is ~150 MHz based on tPLH ≤ 6.2 ns.