SN7476 Dual JK Flip-Flop IC with Preset & Clear – DIP-16

The SN7476 is a digital logic integrated circuit containing two independent JK flip-flops with asynchronous preset and clear inputs. Part of the 7400-series TTL logic family, it is designed for binary counters, data storage, frequency division, and sequential logic applications.

Each flip-flop stores one bit of binary information and provides complementary Q and Q̅ outputs. The J and K inputs determine the next output state, while the preset and clear inputs allow the output to be set or reset independently of the clock.

The SN7476 is suitable for digital electronics experiments, educational projects, and circuit prototyping.

Key Features

• Dual JK Flip-Flops: Two independent flip-flops in a single IC.
• Negative-Edge Triggered: Output changes on the falling edge of the clock.
• Asynchronous Preset and Clear: Active-LOW inputs for setting and resetting each flip-flop.
• Complementary Outputs: Provides Q and Q̅ outputs.
• TTL Logic: Designed for standard 5V digital logic systems.
• Binary Storage: Stores one bit of information per flip-flop.
• Toggle Operation: Supports frequency division and binary counting.
• DIP-16 Package: Suitable for breadboards and through-hole PCB assembly.

Technical Specifications

Pin Configuration

JK Flip-Flop Truth Table

Notes:

• X = Don't Care.
• The last four rows apply during a valid clock cycle.
• Preset and clear operate independently of the clock.
• Simultaneously activating preset and clear should be avoided.

Connection Example

To operate the first JK flip-flop:

1. Connect Pin 5 (VCC) to +5V DC.
2. Connect Pin 13 (GND) to ground.
3. Connect Pin 2 (PRE) and Pin 3 (CLR) to logic HIGH.
4. Connect input J to Pin 4.
5. Connect input K to Pin 16.
6. Apply the clock signal to Pin 1.
7. Read the output from Pin 15 (Q).
8. Use Pin 14 (Q̅) for the inverted output.

Frequency Divider Connection

To configure the first flip-flop as a divide-by-two circuit:

• Connect J (Pin 4) and K (Pin 16) to logic HIGH.
• Keep PRE and CLR HIGH.
• Apply a suitable clock signal to Pin 1.
• Read the divided-frequency output from Pin 15.

The flip-flop toggles once per valid clock cycle, producing an output frequency equal to half the input clock frequency.

Applications

• Binary Counters
• Frequency Divider Circuits
• Digital Data Storage
• Sequential Logic Systems
• Clock Signal Division
• Digital Control Circuits
• Educational Electronics Projects
• Breadboard and PCB Prototyping

Important Notes

• Power Supply: Use a regulated 5V DC supply.
• Clock Operation: The standard SN7476 uses a master-slave configuration. J and K inputs must satisfy the manufacturer's clock timing requirements.
• Preset and Clear: Both asynchronous inputs are active LOW.
• Unused Inputs: Connect unused logic inputs to defined logic levels.
• Decoupling: Use a 100nF capacitor between VCC and GND near the IC.
• Microcontroller Compatibility: Verify voltage compatibility before connecting to ESP32, Raspberry Pi, or other 3.3V devices.
• Variant Differences: SN7476 and SN74LS76 may have different electrical characteristics. Refer to the exact manufacturer's datasheet.

Package Includes

• 1 × SN7476 Dual JK Flip-Flop IC (DIP-16)