7403 Quad 2-Input NAND Gate with Open-Collector Outputs

Overview

The 7403 is a quad 2-input NAND gate integrated circuit belonging to the 7400 series of TTL (Transistor-Transistor Logic) devices. It features open-collector outputs, which allow for wired-AND connections and flexible output configurations. This component is widely used in digital logic design, providing reliable NAND gate functionality in a compact 14-pin DIP (Dual In-line Package) format.

Each of the four independent NAND gates performs the Boolean function Y = A•B or Y = (A AND B)' in positive logic. The open-drain outputs require external pull-up resistors for proper operation when driving high logic levels.

Features

• Quad 2-input NAND gates in single package
• Open-collector outputs for wired-AND applications
• Standard TTL switching voltages
• Wide operating voltage range: 4.75V to 5.25V
• 14-pin DIP package for easy prototyping and production
• Compatible with most TTL and 5V CMOS systems
• Typical propagation delay of 22ns
• Operating temperature range: 0°C to +70°C

Applications

The 7403 finds use in numerous digital logic applications including:

• General purpose logic circuits
• Wired-AND logic implementations
• Bus driver applications
• Interface logic between different voltage systems
• Industrial control systems
• Automotive electronics
• Consumer electronics
• Test and measurement equipment
• Digital signal processing systems

Electrical Characteristics

Absolute Maximum Ratings

• Supply Voltage (VCC): -0.5V to +7V
• DC Input Voltage (VI): -0.5V to VCC + 0.5V
• DC Output Voltage (VO): -0.5V to VCC + 0.5V
• DC Input Diode Current (IIK): ±20mA
• DC Output Current (IO): ±25mA
• Storage Temperature Range: -65°C to +150°C

Recommended Operating Conditions

• Supply Voltage (VCC): 4.75V to 5.25V
• High Level Input Voltage (VIH): 2V min
• Low Level Input Voltage (VIL): 0.8V max
• Operating Temperature Range: 0°C to +70°C

DC Characteristics (VCC = 5V, TA = 25°C)

• High Level Output Current (IOH): -100μA (with external pull-up)
• Low Level Output Current (IOL): 8mA
• High Level Input Current (IIH): 40μA max
• Low Level Input Current (IIL): -1.6mA max
• Supply Current (ICC): 8mA typical, 16mA max

AC Characteristics (VCC = 5V, TA = 25°C)

• Propagation Delay (tPLH): 22ns typical, 30ns max
• Propagation Delay (tPHL): 15ns typical, 22ns max
• Output Transition Time (tTLH): 15ns typical, 22ns max
• Output Transition Time (tTHL): 10ns typical, 15ns max

Package Information

14-Pin DIP Package Details

• Package Type: PDIP-14 (Plastic Dual In-line Package)
• Dimensions: 19.3mm x 6.35mm x 4.57mm (L x W x H)
• Pin Spacing: 2.54mm (0.1") between pins
• Row Spacing: 7.62mm (0.3") between rows
• Lead Material: Copper alloy
• Finish: Matte tin plating
• Weight: Approximately 1.2 grams

Pin Configuration

• Pin 1: 1A (Gate 1 Input A)
• Pin 2: 1B (Gate 1 Input B)
• Pin 3: 1Y (Gate 1 Output)
• Pin 4: 2A (Gate 2 Input A)
• Pin 5: 2B (Gate 2 Input B)
• Pin 6: 2Y (Gate 2 Output)
• Pin 7: GND (Ground)
• Pin 8: 3Y (Gate 3 Output)
• Pin 9: 3A (Gate 3 Input A)
• Pin 10: 3B (Gate 3 Input B)
• Pin 11: 4Y (Gate 4 Output)
• Pin 12: 4A (Gate 4 Input A)
• Pin 13: 4B (Gate 4 Input B)
• Pin 14: VCC (Positive Supply Voltage)

Functional Description

The 7403 contains four independent 2-input NAND gates with open-collector outputs. Each gate implements the logical NAND function where the output is low only when all inputs are high. The truth table for each gate is as follows:

Note: The output requires an external pull-up resistor to provide a high logic level. When the output transistor is off (high impedance state), the pull-up resistor brings the output high. When the output transistor is on, it pulls the output low.

Design Considerations

When using the 7403 in circuit designs, several important factors should be considered:

Power Supply Decoupling

A 0.1μF ceramic capacitor should be placed as close as possible between VCC (pin 14) and