Texas Instruments SN74AHC574PW

Overview

SN74AHC574PW from Texas Instruments is an octal edge-triggered D-type flip-flop with 3-state outputs, designed for bus interface applications requiring high capacitive load drive and voltage translation (5.5 V-tolerant inputs). It operates from 2 V to 5.5 V, features 20-pin TSSOP packaging, supports 110 MHz max frequency at 5 V, and delivers ±8 mA output drive per channel.

For engineers reviewing the SN74AHC574PW datasheet, SN74AHC574PW pinout, SN74AHC574PW application, or SN74AHC574PW equivalent, key selection considerations include its 3-state bus-driving capability, latch-up immunity (>250 mA), ESD robustness (2000 V HBM), and compatibility with mixed-voltage systems (e.g., 5 V → 3.3 V level translation).

Technical Context

The SN74AHC574PW implements eight independent D-type latches synchronized to the rising edge of CLK, with a shared output-enable (OE) control that places all Q outputs in high-impedance state when asserted low. Its CMOS AHC logic family ensures balanced rise/fall times and low dynamic power consumption.

It supports dual-supply interface scenarios via 5.5 V-tolerant inputs while operating at VCC = 2–5.5 V, and incorporates slow-edge design to suppress output ringing on lightly loaded or long-trace buses - critical for stable operation in TV, set-top box, and network switch backplanes.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.50 mm × 6.40 mm body size, 0.65 mm lead pitch, surface-mount, RoHS-compliant, moisture sensitivity level (MSL) 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV574APW and 74AHC574PW, the SN74AHC574PW offers the lowest quiescent current (4 µA) and widest usable VCC range starting at 2 V, making it optimal for battery-sensitive or mixed-voltage industrial control applications.

Availability

SN74AHC574PW is available at Aetrix Electronics and suitable for TV backplanes, network switch data paths, and surveillance camera sensor interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74AHC574PW 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 logic solutions, with decades of heritage in high-reliability logic families.

The SN74AHC574PW belongs to TI's advanced high-speed CMOS (AHC) logic portfolio, engineered for robust bus interface, voltage translation, and noise-immune data latching in industrial, broadcast, and networking equipment.

FAQ

What is the maximum clock frequency supported by the SN74AHC574PW at 3.3 V operation?

The SN74AHC574PW supports a maximum clock frequency of 65 MHz when operated at VCC = 3.3 V ± 0.3 V with CL = 50 pF load, as specified in Section 5.8 of the official datasheet. This value reflects guaranteed timing performance across the full industrial temperature range (–40 °C to +125 °C), and the SN74AHC574PW maintains consistent setup/hold timing margins even under worst-case voltage and temperature conditions.

Does the SN74AHC574PW require external pull-up resistors on its 3-state outputs?

No, the SN74AHC574PW does not require external pull-up resistors on its 3-state outputs. Its 3-state outputs are designed to drive bus lines directly, and the high-impedance state presents negligible leakage (±2.5 µA max IOZ). Pull-ups are only needed if the downstream bus requires a defined logic level during high-Z periods - a system-level decision unrelated to SN74AHC574PW functionality.

Can the SN74AHC574PW safely interface a 5 V microcontroller with a 3.3 V FPGA?

Yes, the SN74AHC574PW can safely interface a 5 V microcontroller with a 3.3 V FPGA. Its inputs are 5.5 V tolerant regardless of VCC setting, allowing direct connection of 5 V logic signals to D and OE pins while VCC = 3.3 V. The SN74AHC574PW outputs swing rail-to-rail (0 V to 3.3 V), matching FPGA input thresholds without level-shifting components.

What is the recommended bypass capacitor for the VCC pin of the SN74AHC574PW?

Texas Instruments recommends a 0.1 µF ceramic bypass capacitor placed as close as possible to the VCC pin (Pin 20) of the SN74AHC574PW. This minimizes high-frequency supply noise and stabilizes switching transients. For systems with multiple SN74AHC574PW devices or high-speed clocking, paralleling a 1 µF tantalum or ceramic capacitor nearby further improves low-frequency decoupling - a practice confirmed in Section 8.3 of the SN74AHC574PW datasheet.

Is the SN74AHC574PW pin-compatible with other 20-pin TSSOP octal flip-flops like the 74AC574?

Yes, the SN74AHC574PW is pin-compatible with industry-standard 20-pin TSSOP octal D-type flip-flops including the 74AC574 and 74LV574A, sharing identical pin functions (OE, CLK, D1–D8, Q1–Q8, GND, VCC) and mechanical footprint. However, electrical differences exist - notably AHC's lower power and wider VCC range versus AC's higher speed but narrower voltage window - so direct substitution requires validation of timing and drive requirements in the target SN74AHC574PW application.