Texas Instruments CD74HCT574QM96Q1

Overview

CD74HCT574QM96Q1 from Texas Instruments is an automotive-qualified octal D-type flip-flop with 3-state outputs, operating at 4.5–5.5 V, delivering 15 ns typical propagation delay (VCC = 5 V, CL = 15 pF), 30 MHz max clock frequency, and bus-line driving capability for 15 LSTTL loads. It serves as a data latch and bus interface in engine control units, ADAS sensor interfaces, and automotive infotainment backplanes.

For engineers reviewing the CD74HCT574QM96Q1 datasheet, CD74HCT574QM96Q1 pinout, CD74HCT574QM96Q1 application, or CD74HCT574QM96Q1 equivalent, key selection criteria include its −40°C to 125°C automotive temperature range, common 3-state output-enable control, buffered inputs, LSTTL/CMOS input compatibility, and SOIC-20 package with verified pin mapping.

Technical Context

This device implements eight edge-triggered D-type flip-flops synchronized on the low-to-high clock transition, with independent 3-state output enable (OE) that places all Q outputs in high-impedance state regardless of register state. Its logic diagram confirms non-inverting outputs and separate OE control path decoupled from clock and data paths.

It features balanced propagation delay and transition times, direct LSTTL-compatible input thresholds (VIL ≤ 0.8 V, VIH ≥ 2 V), and CMOS-level input leakage (< ±1 µA). The design supports stable bus sharing via tri-state control and meets AEC-Q100 stress test requirements for automotive use.

Key Specifications

Pinout & Package

CD74HCT574QM96Q1 is housed in a 20-pin SOIC (DW) package, 7.5 mm × 12.8 mm body size, 2.65 mm max height, with 1.27 mm lead pitch and RoHS-compliant NiPdAu finish. Moisture sensitivity level is Level-1 (unlimited reflow).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal D-type latch applications.

Compared with CD74HCT574QM96Q1, SN74HCT574QPWRQ1 offers identical functionality in a smaller footprint but with reduced thermal performance, while CD74ACT574M96E trades automotive qualification for higher speed and 3.3 V tolerance-neither is a drop-in replacement without layout or qualification review.

Availability

CD74HCT574QM96Q1 is available at Aetrix Electronics and suitable for engine control units, ADAS sensor interfaces, and automotive infotainment systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74HCT574QM96Q1 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-grade logic solutions, with decades of automotive qualification expertise and manufacturing scale.

The CD74HCT574-Q1 product line delivers radiation-hardened, temperature-robust logic building blocks specifically engineered for automotive powertrain, chassis, and ADAS subsystems demanding AEC-Q100 compliance.

FAQ

What is the maximum clock frequency supported by CD74HCT574QM96Q1 across its full temperature range?

The CD74HCT574QM96Q1 supports up to 30 MHz at TA = 25°C, derating to 20 MHz over the full −40°C to +125°C operating range per TI's SCLS570A datasheet. This specification reflects guaranteed timing margins under worst-case voltage (4.5 V) and capacitive loading (CL = 15 pF), ensuring reliable operation in engine bay environments where thermal and supply variation occur.

Does CD74HCT574QM96Q1 require external pull-up or pull-down resistors on unused inputs?

Yes, CD74HCT574QM96Q1 requires all unused inputs-including D0–D7, CP, and OE-to be tied to either VCC or GND. Floating inputs can cause increased ICC, erratic output behavior, or latch-up due to CMOS input structure; TI's SCBA004 application report explicitly mandates this for proper device operation and reliability in automotive applications.

Can CD74HCT574QM96Q1 drive standard 5 V TTL loads directly without level-shifting circuitry?

Yes, CD74HCT574QM96Q1 provides direct LSTTL input compatibility (VIL ≤ 0.8 V, VIH ≥ 2 V) and outputs VOH ≥ 3.98 V / VOL ≤ 0.26 V at 6 mA load, meeting TTL voltage thresholds. Its 15 LSTTL load drive capability means it can interface natively with legacy 74LS-series logic without translators or buffers in automotive control modules.

What is the meaning of the "Q1" suffix in CD74HCT574QM96Q1?

The "Q1" suffix in CD74HCT574QM96Q1 denotes Texas Instruments' automotive-grade qualification per AEC-Q100 standards, including enhanced testing for temperature cycling, humidity bias, and ESD robustness. It also indicates extended temperature range (−40°C to +125°C), controlled manufacturing flow, and traceable lot documentation required for Tier 1 automotive supply chains.

How does the 3-state output enable (OE) function interact with the internal register state of CD74HCT574QM96Q1?

The OE pin on CD74HCT574QM96Q1 operates independently of the internal flip-flop registers: when OE is high, all Q0–Q7 outputs go high-impedance regardless of stored data or clock activity; the register contents remain intact and unaffected. This allows safe bus sharing and dynamic output arbitration without disrupting ongoing data capture operations in systems like multi-sensor fusion controllers.