The 74LS series of integrated circuits (ICs) was one of the most popular logic families of transistor-transistor logic (TTL) logic chips. 74LS series is a bipolar, low-power Schottky IC. The 74LS682 is an 8-bit magnitude comparator. 74LS682 device is designed to perform comparisons between two eight-bit binary or BCD words. All device types provide P = Q outputs and the LS682 and LS684 have P>Q outputs also.

74LS682 Features
- Designed to Perform Comparisons Between Two 8-bit Binary or BCD Words
- Includes Pull-Up Resistor on the Input
- Provides Greater Than or Equal Comparison Result
- Operating Temperature up to 70°C
- Standard TTL Switching Voltages
74LS682 Specifications
Supply Voltage | 4.75 – 5.25Vdc |
Maximum Clock Frequency | 40Mhz |
Power Dissipation | 2mW/gate @100kHz |
Minimum Output Current | 8mA |
Propagation Delay | 10nS |
Fan Out (TTL Loads) | 20 |
74LS682 Pinout Diagram

74LS682 Pin Description
Pin No | Pin Name | Description |
1 | P>Q | Output Pin When P is greater than Q |
2 | P0 | Bit 0 of Comparator 1 |
3 | Q0 | Bit 0 of Comparator 2 |
4 | P1 | Bit 1 of Comparator 1 |
5 | Q1 | Bit 1 of Comparator 2 |
6 | P2 | Bit 2 of Comparator 1 |
7 | Q2 | Bit 2 of Comparator 2 |
8 | P3 | Bit 3 of Comparator 1 |
9 | Q3 | Bit 3 of Comparator 2 |
10 | GND | Ground |
11 | P4 | Bit 4 of Comparator 1 |
12 | Q4 | Bit 4 of Comparator 2 |
13 | P5 | Bit 5 of Comparator 1 |
14 | Q5 | Bit 5 of Comparator 2 |
15 | P6 | Bit 6 of Comparator 1 |
16 | Q6 | Bit 6 of Comparator 2 |
17 | P7 | Bit 7 of Comparator 1 |
18 | Q7 | Bit 7 of Comparator 2 |
19 | P’=Q’ | Comparator Equal Output Pin |
20 | VCC | Positive Supply |
74LS682 Circuit
Here is a simple circuit of a 1-bit comparator using logic gates.

Applications
- Null detectors
- Zero-crossing detectors
- Relaxation oscillator
- Level shifter
- Analog-to-digital converters
74LS682 Alternative Equivalent
74LS688
Download 74LS682 8-bit Magnitude Comparator Datasheet from the link given below.