IC 74574 – Octal D-Type Flip-Flop with 3-State Outputs

IC 74574 – Octal D-Type Flip-Flop with 3-State Outputs

Overview

The IC 74574 is an octal D-type flip-flop integrated circuit that provides eight independent D-type flip-flops in a single package. Each flip-flop features a data input, a clock input, and asynchronous set and reset inputs. This IC is commonly used for data storage, buffering, and timing applications in digital circuits.

Features

• Octal Flip-Flops: Contains eight independent D-type flip-flops.
• 3-State Outputs: Each output can be in one of three states: high, low, or high-impedance (tri-state).
• Asynchronous Set and Reset: Each flip-flop has asynchronous set (PRE) and reset (CLR) inputs for immediate control of the flip-flop state.
• Clocked Operation: Data is captured on the rising or falling edge of the clock signal.
• Buffered Outputs: Outputs are buffered to drive larger loads.

Pin Configuration

The IC 74574 is typically available in a 20-pin Dual In-line Package (DIP) format. The pinout is as follows:

• Pins 1-8: Q0 to Q7 (Parallel Outputs of Flip-Flops 0 to 7)
• Pins 9-10: GND (Ground)
• Pin 11: Vcc (Positive Supply Voltage)
• Pins 12-19: D0 to D7 (Data Inputs for Flip-Flops 0 to 7)
• Pin 20: CLK (Clock Input for all Flip-Flops)
• Pin 21: CLR (Asynchronous Reset Input for all Flip-Flops)
• Pin 22: PRE (Asynchronous Set Input for all Flip-Flops)
• Pin 23: OE (Output Enable for all Flip-Flops)

Working Principle

The IC 74574 operates as follows:

1. Data Storage: Data is loaded into each flip-flop from the D (data) input on the clock edge, and the stored data is output through the Q pin.
2. Clock Signal: The CLK (clock) input controls when data is captured into the flip-flops. The flip-flops are edge-triggered, capturing data on the rising or falling edge of the clock signal.
3. Asynchronous Control: The CLR (reset) and PRE (set) inputs can immediately clear or set the state of the flip-flops regardless of the clock signal.
4. 3-State Outputs: The outputs can be set to high, low, or high-impedance state based on the OE (output enable) input.

Applications

• Data Storage: Provides temporary storage of data in digital systems.
• Buffers: Acts as a buffer to drive high-current loads or to isolate different parts of a circuit.
• Registers: Used in registers for storing and transferring data in digital systems.
• Data Handling: Useful in systems requiring parallel data transfer and manipulation.

Example Circuit

• Data Register: Configure the IC to store data from a microcontroller or other digital device, and output the data in parallel.
• Buffering: Use the IC to buffer signals between different parts of a circuit, ensuring signal integrity and driving capability.

Advantages

• Octal Configuration: Provides eight flip-flops in a single package, saving space and simplifying circuit design.
• 3-State Outputs: Allows for flexible interfacing with other digital components and bus systems.
• Asynchronous Control: Includes asynchronous set and reset inputs for immediate control of flip-flop states.
• Buffered Outputs: Capable of driving larger loads compared to unbuffered flip-flops.

Conclusion

The IC 74574 is a versatile and efficient octal D-type flip-flop IC that is well-suited for data storage, buffering, and parallel data handling applications. Its features, including 3-state outputs and asynchronous control inputs, make it a valuable component in digital circuits requiring reliable data management and flexible interfacing. With its eight flip-flops and robust design, the IC 74574 provides an effective solution for a wide range of digital logic needs.

IC 4013 – Dual D-Type Flip-Flop