Texas Instruments SN74ALVCH16245DGGR

Overview

SN74ALVCH16245 from Texas Instruments is a 16-bit dual-octal noninverting bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between two 16-bit buses operating at 1.65 V to 3.6 V. It features ±24-mA output drive at 3.3 V, 3 ns max propagation delay, bus-hold on all data inputs, and 5.5-V tolerant inputs for down-translation (e.g., 5 V → 3.3 V). It is used in server backplanes and telecom infrastructure where level-shifting and high-drive bus isolation are required.

For engineers reviewing the SN74ALVCH16245 datasheet, SN74ALVCH16245 pinout, SN74ALVCH16245 application, or SN74ALVCH16245 equivalent, key selection criteria include direction-control logic behavior, 3-state enable timing (ten/tdis), bus-hold current specs, thermal resistance (RθJA = 63°C/W for TSSOP), and compatibility with mixed-voltage I/O domains.

Technical Context

The SN74ALVCH16245 implements dual independent 8-bit transceivers, each controlled by dedicated DIR and OE inputs. Direction is determined by DIR logic level (high = A→B, low = B→A), while OE enables/disables outputs into high-impedance state - both controls operate asynchronously with no internal clocking.

Its CMOS design includes active bus-hold circuitry on all 32 I/O pins (16 A + 16 B), eliminating external pull resistors, and supports overvoltage-tolerant inputs up to 5.5 V regardless of VCC (1.65–3.6 V), enabling robust level translation without additional interface logic.

Key Specifications

Pinout & Package

TSSOP-48 package (DGG), 6.10 mm × 12.50 mm body size, 0.5-mm pitch, lead-free NiPdAu finish, moisture sensitivity level 1 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC16245ADGGR and SN74AVC16245DGGR, the SN74ALVCH16245 provides unique integration of bus-hold, 5.5-V tolerance across full VCC range, and consistent ±24-mA drive - making it optimal for industrial backplanes and telecom line cards where reliability under undriven conditions and mixed-voltage interoperability are mandatory.

Availability

SN74ALVCH16245DGGR is available at Aetrix Electronics and suitable for cable modem termination systems, industrial server backplanes, and telecom line card interfaces requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for SN74ALVCH16245DGGR 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 specializing in analog, embedded processing, and logic solutions, with leadership in industrial, automotive, and communications markets.

The SN74ALVCH16245 belongs to TI's Widebus™ family of high-performance bus interface devices, engineered for robust bidirectional data transfer in mixed-voltage, high-noise industrial and telecom environments.

FAQ

What is the maximum input voltage the SN74ALVCH16245 can tolerate regardless of VCC?

The SN74ALVCH16245 supports 5.5-V tolerant inputs across its entire 1.65-V to 3.6-V VCC operating range. This means inputs can safely accept up to 5.5 V even when VCC is as low as 1.65 V - a key enabler for down-translation applications such as interfacing 5-V legacy peripherals to modern low-voltage processors. This specification is verified per Absolute Maximum Ratings and confirmed in the Feature Description section of the datasheet.

How does the bus-hold feature on the SN74ALVCH16245 eliminate external resistors?

The SN74ALVCH16245 integrates active bus-hold circuitry on all 32 A- and B-side I/O pins, providing ±75 µA holding current at 3 V to maintain valid logic states on undriven or floating inputs. Because this internal circuitry actively sustains logic levels, external pullup or pulldown resistors become redundant - reducing BOM cost, PCB real estate, and potential signal integrity issues caused by resistor parasitics. The datasheet explicitly states that using external resistors with bus-hold is not recommended.

What are the functional differences between 1DIR/2DIR and 1OE/2OE on the SN74ALVCH16245?

On the SN74ALVCH16245, 1DIR and 2DIR independently control data direction for the first and second octet (1A↔1B and 2A↔2B), while 1OE and 2OE independently enable or disable the corresponding 8-bit output ports. This allows asymmetric operation - for example, 1OE = L and 2OE = H lets the first octet pass data bidirectionally while the second octet remains isolated. This granularity supports complex bus arbitration schemes in multi-processor or hot-swap systems without requiring additional logic.

Can the SN74ALVCH16245 operate reliably at 1.65 V VCC with full output drive capability?

Yes - the SN74ALVCH16245 is fully specified down to 1.65 V VCC, including output drive (±4 mA at 1.65 V), propagation delay (max 3.7 ns), and input thresholds (VIH = 0.65×VCC, VIL = 0.35×VCC). Its design ensures stable 3-state operation, bus-hold functionality, and ESD robustness (2000-V HBM) across the entire 1.65–3.6-V range, making it suitable for battery-powered or ultra-low-power industrial controllers where supply headroom is constrained.

Why does the SN74ALVCH16245 have eight GND pins and four VCC pins in its TSSOP-48 package?

The SN74ALVCH16245 allocates eight GND and four VCC pins in its TSSOP-48 package to minimize ground bounce and supply noise during high-speed, high-current switching. With ±24-mA drive capability and 32 actively switching I/Os, distributed power/ground connections reduce loop inductance, suppress simultaneous switching noise (SSN), and maintain signal integrity - especially critical in dense backplane or high-density server applications. Thermal data confirms RθJA = 63°C/W reflects this optimized pinout for thermal dissipation.