Texas Instruments CAHCT244QDWRG4Q1

Overview

CAHCT244QDWRG4Q1 from Texas Instruments is an automotive-qualified octal 3-state buffer/driver with dual independent output-enable controls, TTL-compatible inputs, ±8 mA drive strength at 5 V, and operation over −40°C to +125°C. It functions as a bidirectional bus interface or signal gating device in engine control units, ADAS domain controllers, and body electronics modules.

For engineers reviewing the CAHCT244QDWRG4Q1 datasheet, CAHCT244QDWRG4Q1 pinout, CAHCT244QDWRG4Q1 application, or CAHCT244QDWRG4Q1 equivalent, key selection criteria include its AEC-Q100 Grade 1 qualification, SOIC-20 package thermal performance (R_θJA = 58°C/W), 3-state timing (t_PZH/t_PHZ ≤ 12 ns @ 15 pF), and compatibility with 5-V logic systems requiring noise-immune signal routing.

Technical Context

The CAHCT244QDWRG4Q1 implements two independent 4-bit non-inverting buffers, each with dedicated output-enable (OE) inputs-1OE controls Y1–Y4, 2OE controls Y5–Y8. Its EPIC™ CMOS process ensures TTL-level input thresholds (V_IL = 0.8 V, V_VIH = 2.0 V) while maintaining CMOS power efficiency (I_CC ≤ 40 μA).

Functional mode is strictly defined: when OE is low, A→Y pass-through occurs with t_PLH/t_PHL = 5.4–8.5 ns (CL = 15 pF); when OE is high, outputs enter high-impedance state with leakage ≤ ±0.25 μA. No internal pull-ups or level-shifting circuitry is present-external biasing is required for power-up safety.

Key Specifications

Pinout & Package

CAHCT244QDWRG4Q1 uses a 20-pin SOIC (DW) package with 12.8 mm × 10.3 mm footprint and 2.65 mm max height. Pin 1 index area is marked by a beveled corner; leads are gull-wing with 1.27 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal buffer applications.

Compared with SN74AHCT244QPWRG4Q1 and SN74LVC244AQPWRQ1, CAHCT244QDWRG4Q1 uniquely combines 5-V TTL compatibility, SOIC thermal performance, and AEC-Q100 Grade 1 qualification-making it the sole option for legacy 5-V automotive bus interfaces requiring industrial-grade reliability.

Availability

CAHCT244QDWRG4Q1 is available at Aetrix Electronics and suitable for engine control units, ADAS camera interfaces, and body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CAHCT244QDWRG4Q1 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 automotive ICs, with decades of experience in AEC-Q100-qualified logic solutions.

The SN74AHCT244-Q1 product line delivers automotive-grade octal buffers optimized for noise-immune signal routing in powertrain, chassis, and infotainment systems-designed specifically to replace legacy 74-series logic in harsh-temperature environments.

FAQ

What is the maximum operating temperature for CAHCT244QDWRG4Q1?

The CAHCT244QDWRG4Q1 is rated for operation from −40°C to +125°C ambient, meeting AEC-Q100 Grade 1 requirements. This specification is validated across all electrical parameters in the datasheet-including propagation delay, drive strength, and leakage-under full temperature range testing, not just thermal limits. The CAHCT244QDWRG4Q1 maintains guaranteed timing and logic behavior throughout this range without derating.

Does CAHCT244QDWRG4Q1 support 3.3-V input logic levels?

No, CAHCT244QDWRG4Q1 does not reliably accept 3.3-V inputs as valid logic-high signals. Its V_IH threshold is fixed at 2.0 V minimum (per 5.3 Recommended Operating Conditions), but the device is designed for 5-V supply and TTL-compatible sources. Applying 3.3-V signals risks marginal switching and increased noise susceptibility; use SN74LVC244AQPWRQ1 instead for native 3.3-V systems. The CAHCT244QDWRG4Q1 requires true 5-V input sources.

How should unused inputs be handled on CAHCT244QDWRG4Q1?

All unused inputs on CAHCT244QDWRG4Q1 must be tied to either V_CC or GND-floating inputs cause undefined output states and increased ICC. TI's SCBA004 application report specifies that unconnected inputs may draw excessive current or oscillate due to internal capacitance. For CAHCT244QDWRG4Q1, tie unused A-inputs directly to V_CC (for logic-high default) or GND (for logic-low), using short traces and avoiding resistive pulls unless noise immunity is critical.

Is CAHCT244QDWRG4Q1 pin-compatible with standard SN74AHCT244 devices?

Yes, CAHCT244QDWRG4Q1 shares identical pinout, function mapping, and electrical behavior with non-automotive SN74AHCT244 variants in the same SOIC-20 (DW) package-including SN74AHCT244N and SN74AHCT244D. However, CAHCT244QDWRG4Q1 adds AEC-Q100 qualification, enhanced ESD protection (±1000 V HBM), and extended temperature screening. No PCB changes are needed when upgrading from catalog versions to CAHCT244QDWRG4Q1.

What is the recommended bypass capacitor for CAHCT244QDWRG4Q1?

Texas Instruments recommends a 0.1-μF ceramic capacitor placed within 3 mm of the V_CC pin (Pin 20) for CAHCT244QDWRG4Q1. This value targets high-frequency noise suppression (10–100 MHz). For systems with multiple CAHCT244QDWRG4Q1 devices or high di/dt loads, add a bulk 1-μF tantalum or aluminum electrolytic capacitor near the power entry point. The CAHCT244QDWRG4Q1 datasheet explicitly states that improper bypassing causes timing violations and output instability.