Texas Instruments SN74ABT853PWG4

Overview

SN74ABT853PWG4 from Texas Instruments is an 8-bit to 9-bit parity bus transceiver with integrated parity generator/checker, ERR flag latch, and high-drive outputs (−32 mA IOH, 64 mA IOL). It operates from 4.5 V to 5.5 V over −40°C to 85°C and supports bidirectional data transfer between A and B buses with real-time odd-parity generation and error detection in industrial backplane and memory subsystem applications.

For engineers reviewing the SN74ABT853PWG4 datasheet, SN74ABT853PWG4 pinout, SN74ABT853PWG4 application, or SN74ABT853PWG4 equivalent, this device delivers deterministic parity-error flag assertion, latchable/clearable ERR output, high-impedance isolation during power sequencing, and EPIC-II™ BiCMOS logic for low ground bounce (<1 V VOLP) and ESD robustness (>2 kV HBM).

Technical Context

The SN74ABT853PWG4 implements a dual-bus transceiver architecture with dedicated parity logic: an 8-bit A bus and 8-bit B bus interface plus PARITY and ERR open-collector outputs. Its control inputs-OEA, OEB, LE, and CLR-orchestrate direction, enable, error sampling, and flag reset without external timing components.

It features true data propagation (non-inverting), inverted-parity mode for diagnostic forcing, and power-up/down high-impedance behavior below 2.1 V VCC. The ERR output reflects parity mismatch status at point P in the internal logic, and its state can be latched, cleared, or passed transparently based on LE/CLR timing per the error-flag function table.

Key Specifications

Pinout & Package

TSSOP-24 (PW) package: 7.8 mm × 4.4 mm body, 0.65 mm pitch, surface-mount, RoHS-compliant lead finish (NiPdAu), moisture sensitivity level 1 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit parity transceiver applications.

Compared with SN74ABT823DW and SN74LVC8T245PW, the SN74ABT853PWG4 uniquely integrates parity generation, checking, and latched error reporting in a single TSSOP-24 package - eliminating four to six discrete ICs and associated timing constraints in legacy 5-V bus architectures.

Availability

SN74ABT853PWG4 is available at Aetrix Electronics and suitable for industrial backplane interconnect, memory subsystem parity handling, test equipment data integrity verification, and legacy system bus expansion requiring stable component supply and long-term lifecycle support.

Supply support for SN74ABT853PWG4 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 logic solutions with emphasis on reliability, performance, and broad application coverage.

The SN74ABT853PWG4 belongs to TI's ABT logic family - designed specifically for high-speed, low-noise 5-V bus transceivers with integrated parity and diagnostic features for industrial and computing infrastructure.

FAQ

What is the function of the LE and CLR pins on the SN74ABT853PWG4?

The LE (Latch Enable) pin captures the current state of the ERR output into an internal register on its active edge, holding the error flag even after the parity mismatch clears. The CLR (Clear) pin is an asynchronous active-low input that forces the ERR latch to reset and drives ERR high regardless of ongoing parity status. Both functions are essential for reliable fault logging in systems without continuous ERR monitoring - ensuring SN74ABT853PWG4 maintains diagnostic visibility across software polling intervals.

Does the SN74ABT853PWG4 support hot-swap or live-insertion scenarios?

Yes - the SN74ABT853PWG4 enters a guaranteed high-impedance state when VCC is below 2.1 V, preventing bus contention during partial power-up or insertion. Combined with its >2000 V HBM ESD rating and bus-isolation capability (via OEA/OEB high), it meets key requirements for controlled hot-swap in modular backplanes. However, external current-limiting and sequencing must still manage inrush; SN74ABT853PWG4 alone does not provide full hot-swap power management.

Can the SN74ABT853PWG4 generate even parity instead of odd parity?

No - the SN74ABT853PWG4 is hardwired for odd-parity generation and checking. However, its inverted-parity mode (activated when both OEA and OEB are low) forces an even-parity result on the PARITY output, creating a deliberate mismatch during B→A transfer. This is not configurable even-parity operation but a diagnostic feature to verify ERR assertion and latch behavior - the core parity logic remains odd-only per datasheet specification for SN74ABT853PWG4.

What is the maximum capacitive load the SN74ABT853PWG4 can drive on the B bus?

The SN74ABT853PWG4 is characterized to drive up to 64 mA low-level output current (IOL) and −32 mA high-level (IOH), supporting typical bus loads of ≤50 pF per node as verified in switching characteristics testing. With CL = 50 pF, propagation delays remain within 1.2–6.4 ns. For heavier loads (>70 pF), rise/fall times degrade and VOLP increases - design validation with actual trace capacitance is recommended. SN74ABT853PWG4 does not specify a maximum absolute capacitance limit, only parametric performance at 50 pF.

Is the ERR output of the SN74ABT853PWG4 compatible with 3.3-V logic inputs?

Yes - the ERR output is open-collector and requires an external pull-up resistor. When pulled to 3.3 V, its low-state voltage (VOL) is ≤0.55 V at 64 mA sink, well within 3.3-V logic low threshold (≤0.8 V). Its high-state is defined by the pull-up voltage, making SN74ABT853PWG4 directly interoperable with 3.3-V controllers without level-shifting, provided the pull-up resistor value limits current to within ERR's 50 μA leakage spec when high and supports required rise time.