7486 Quad 2-Input XOR Gate Technical Summary

Overview

The 7486 is a quad 2-input exclusive OR (XOR) gate integrated circuit belonging to the 7400 series of TTL logic devices. This component contains four independent XOR gates, each performing the logical XOR function. The XOR operation outputs a HIGH (1) when the inputs are different and a LOW (0) when they are identical. The 7486 is widely used in digital systems for arithmetic operations, error detection, and data comparison applications.

Built using transistor-transistor logic (TTL) technology, the 7486 offers reliable performance with standard power supply requirements. The device is characterized for operation from 0°C to 70°C, making it suitable for commercial applications.

Features

• Quad 2-input XOR gates in single package
• Standard TTL switching voltages
• Fully compatible with most TTL and DTL logic families
• Typical propagation delay of 22ns
• Low power consumption: 10mW typical per gate
• Wide operating voltage range: 4.75V to 5.25V
• Fan-out of 10 TTL loads
• Available in PDIP, SOIC, and other package options

Applications

The 7486 finds use in numerous digital applications including:

• Binary addition circuits (half-adders and full-adders)
• Parity generators and checkers
• Data comparison circuits
• Error detection systems
• Controlled inversion circuits
• Digital encryption systems
• Pseudo-random number generators
• Phase comparators

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 Diode Current (IOK): ±20mA
• DC Output Current (IO): ±25mA
• DC Supply Current per Output (ICC): ±50mA
• Storage Temperature Range (TSTG): -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 (TA): 0°C to 70°C

DC Characteristics

• High-Level Output Voltage (VOH): 2.7V min (VCC = min, IOH = -400μA)
• Low-Level Output Voltage (VOL): 0.4V max (VCC = min, IOL = 16mA)
• Input Clamp Voltage (VIK): -1.5V max (VCC = min, II = -18mA)
• High-Level Input Current (IIH): 40μA max (VCC = max, VI = 2.7V)
• Low-Level Input Current (IIL): -1.6mA max (VCC = max, VI = 0.4V)
• Short-Circuit Output Current (IOS): -20mA to -100mA (VCC = max)
• Supply Current (ICC): 8mA max (VCC = max, all gates switching)

AC Characteristics

• Propagation Delay Time (tPLH, tPHL): 22ns max (CL = 15pF, RL = 400Ω)
• Output Transition Time (tTLH, tTHL): 15ns max (CL = 15pF, RL = 400Ω)

Pin Configuration and Truth Table

Pin Description

• Pin 1, 4, 9, 12: 1A to 4A (Data Inputs for gates 1 through 4)
• Pin 2, 5, 10, 13: 1B to 4B (Data Inputs for gates 1 through 4)
• Pin 3, 6, 8, 11: 1Y to 4Y (Data Outputs for gates 1 through 4)
• Pin 7: GND (Ground, 0V reference)
• Pin 14: VCC (Positive supply voltage, +5V nominal)

Truth Table (Per Gate)

Package Information

The 7486 is available in several package options:

14-Pin Plastic Dual In-Line Package (PDIP)

• JEDEC MS-001 standard
• Body width: 300 mil
• Lead pitch: 100 mil
• Package dimensions: 19.3mm x 6.35mm x 4.57mm

14-Pin Small Outline Integrated Circuit (SOIC)

• JEDEC MS-012 standard
• Body width: 3.9mm
• Lead pitch: 1.27mm
• Package dimensions: 8.65mm x 3.9mm x 1.75mm

14-Pin Thin Shrink Small Outline Package (TSSOP)

• Body width: 4.4mm
• Lead pitch: 0.65mm
• Package dimensions: 5mm x 4.4mm x 1mm

Functional Description

Each of the four XOR gates in the 7486 implements the Boolean function Y = A⊕B = (A•B') + (A'•B). The gates operate independently and can be used in parallel for multiple XOR operations. The device features standard TTL input buffering with input clamp diodes for protection against voltage transients.

The output stage uses a totem-pole configuration providing both active pull-up and pull-down, enabling fast switching speeds and good noise immunity. When driving capacitive loads, a small series resistor (typically 100-200Ω) is recommended to limit output current