Texas Instruments SN74ALVCH16646DGGR

Overview

SN74ALVCH16646 from Texas Instruments is a 16-bit bus transceiver and register with 3-state outputs, designed for bidirectional data flow control between two 8-bit buses (A and B) in low-voltage systems. It operates from 1.65 V to 3.6 V, supports clocked register storage on both buses, and features bus-hold circuitry eliminating external pullup/pulldown resistors - used in memory interface buffering and FPGA-to-ASIC interconnect applications.

For engineers reviewing the SN74ALVCH16646 datasheet, SN74ALVCH16646 pinout, SN74ALVCH16646 application, or SN74ALVCH16646 equivalent, key selection criteria include dual-clock edge-triggered register capability, independent DIR/OE/SAB/SBA control logic, 3.6-V absolute maximum rating, -40°C to 85°C industrial temperature range, and TSSOP-56 package compatibility with high-density PCB layouts.

Technical Context

The SN74ALVCH16646 implements two independent 8-bit transceiver/register blocks, each with separate CLKAB/CLKBA, DIR, OE, SAB/SBA controls. Data latching occurs on low-to-high clock transitions, enabling synchronous capture of A→B or B→A bus data into internal registers before output enable.

Its EPIC™ submicron CMOS process delivers rail-to-rail input thresholds (VIH/VIL scaling with VCC), 150-MHz max clock frequency, and active bus-hold on all A/B I/O pins - ensuring stable logic levels during floating-bus conditions without external components.

Key Specifications

Pinout & Package

TSSOP-56 (DGG) package: 12.5 mm × 6.1 mm footprint, 0.5-mm lead pitch, 1.2-mm max height, JEDEC MO-153 compliant, RoHS-compliant NiPdAu lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ALVCH16646, SN74ALVCH162245DGGR omits register and select-control logic - simplifying design at the cost of synchronous data staging - while SN74LVC16646DGGR trades bus-hold for higher drive strength, demanding external termination for floating inputs.

Availability

SN74ALVCH16646 is available at Aetrix Electronics and suitable for memory interface buffering, FPGA-to-ASIC interconnect, and industrial backplane interface applications requiring stable component supply across extended production lifecycles.

Supply support for SN74ALVCH16646 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 experience in high-reliability logic and interface solutions.

The SN74ALVCH16646 belongs to TI's Widebus™ family of advanced bus-interface ICs, engineered specifically for high-speed, low-voltage bidirectional data transfer in industrial, computing, and communications infrastructure.

FAQ

What is the primary function of the SN74ALVCH16646?

The SN74ALVCH16646 is a 16-bit bus transceiver and register with 3-state outputs. It enables bidirectional data transfer between two 8-bit buses (A and B), supports synchronous data capture via clocked registers, and provides selectable real-time or stored data output using SAB/SBA controls - all within a single 1.65-V to 3.6-V supply domain.

Does the SN74ALVCH16646 require external pullup resistors on its I/O pins?

No. The SN74ALVCH16646 integrates active bus-hold circuitry on all A and B port inputs, maintaining valid logic levels on floating or unused pins without external pullup or pulldown resistors - reducing BOM count and improving noise immunity in industrial environments.

What package type is used for the SN74ALVCH16646DGGR variant?

The SN74ALVCH16646DGGR uses a 56-pin Thin Shrink Small-Outline Package (TSSOP-DGG), measuring 12.5 mm × 6.1 mm with 0.5-mm lead pitch and 1.2-mm maximum height. It complies with JEDEC MO-153 and carries RoHS-compliant NiPdAu plating with MSL Level-1 rating.

Can the SN74ALVCH16646 operate at 1.8 V and still meet timing specifications?

Yes. The SN74ALVCH16646 is fully characterized from 1.65 V to 3.6 V. At 1.8 V, it supports a minimum clock pulse width of 3.3 ns and propagation delay of ≤5.6 ns, enabling reliable operation in low-power 1.8-V systems such as portable instrumentation and battery-powered controllers.

How does the SN74ALVCH16646 handle power-up and power-down sequencing?

To ensure high-impedance outputs during power-up/down, OE should be tied to VCC through a pullup resistor. The SN74ALVCH16646's internal circuitry guarantees that outputs remain in 3-state until VCC stabilizes, preventing bus contention - a critical feature for hot-plug and fail-safe system architectures.