74HC574 Octal D Flip-Flop IC – 8-Bit Positive-Edge Triggered with 3-State Outputs

Overview

The 74HC574 Octal D Flip-Flop is a high-speed, 8-bit storage register. Unlike a latch (which stays “open” while the enable pin is high), the 574 is edge-triggered. It captures the data on all 8 input pins at the exact moment the clock (CP) transitions from Low to High. This makes it incredibly stable for high-speed digital systems where you need to sync data perfectly with a system clock. Its 3-state outputs allow it to sit directly on a microprocessor bus without causing data collisions.

Key Features

• Flow-Through Architecture: Inputs (D0-D7) are on pins 2–9, and outputs (Q0-Q7) are on pins 19–12. This makes breadboarding a breeze and PCB traces much shorter.

• Edge-Triggered Storage: Data is “clocked in” on the rising edge, ensuring no accidental data leaks during level changes.

• 3-State Logic: The Output Enable (\overline{OE}) pin can disconnect the IC from the bus, allowing multiple devices to share the same lines.

• High-Speed Performance: Designed with silicon-gate CMOS technology, achieving speeds comparable to LS-TTL but with drastically lower power consumption.

• Robust Compatibility: Works across a 2V to 6V range, making it ideal for both classic Arduino and modern 3.3V ARM/ESP32 projects.

Technical Specifications