74HC688D,652

Product Overview

Category: Integrated Circuit (IC)

Use: The 74HC688D,652 is a high-speed CMOS 8-bit magnitude comparator that performs comparison of two 8-bit binary or BCD numbers. It is commonly used in digital systems for various applications such as arithmetic operations, data processing, and control circuits.

Characteristics: - High-speed operation - Low power consumption - Wide operating voltage range - Compatibility with TTL levels - Schmitt-trigger action on all inputs - ESD protection on all inputs and outputs

Package: The 74HC688D,652 is available in a small outline package (SO) with 20 pins. This package provides easy integration into circuit boards and ensures efficient heat dissipation.

Essence: The essence of the 74HC688D,652 lies in its ability to compare two 8-bit binary or BCD numbers and provide output signals indicating their relative magnitudes.

Packaging/Quantity: The 74HC688D,652 is typically sold in reels or tubes containing multiple units. The exact quantity may vary depending on the supplier.

Specifications

• Supply Voltage Range: 2V to 6V
• Input Voltage Range: 0V to VCC
• Operating Temperature Range: -40°C to +125°C
• Propagation Delay: 12 ns (typical)
• Output Current: ±25 mA

Pin Configuration

The 74HC688D,652 has a total of 20 pins arranged as follows:

+---+--+---+ A1 -|1 +--+ 20|- VCC A2 -|2 |- B1 A3 -|3 |- B2 A4 -|4 |- B3 A5 -|5 |- B4 A6 -|6 |- B5 A7 -|7 |- B6 A8 -|8 |- B7 GND -|9 |- B8 O1A -|10 |- O2A O1B -|11 |- O2B O1C -|12 |- O2C O1D -|13 |- O2D O1E -|14 |- O2E O1F -|15 |- O2F O1G -|16 |- O2G O1H -|17 |- O2H GND -|18 |- GND +----------+

Functional Features

The 74HC688D,652 offers the following functional features:

• 8-bit magnitude comparison: It can compare two 8-bit binary or BCD numbers and determine their relative magnitudes.
• Output signals: The comparator provides eight output signals (O1A to O1H) indicating the result of the comparison.
• Enable input: The device has an active-low enable input (G) that allows or inhibits the comparison operation.

Advantages and Disadvantages

Advantages: - High-speed operation enables efficient processing of data. - Low power consumption helps in reducing overall system energy requirements. - Wide operating voltage range allows compatibility with various power supply configurations. - Schmitt-trigger action on inputs ensures noise immunity and reliable operation. - ESD protection on inputs and outputs enhances device durability.

Disadvantages: - Limited to 8-bit magnitude comparison, may not be suitable for applications requiring larger bit widths. - Requires external circuitry for handling carry/borrow operations in multi-bit comparisons.

Working Principles

The 74HC688D,652 performs magnitude comparison by internally subtracting the two input numbers and analyzing the resulting carry/borrow signals. It utilizes CMOS technology to achieve high-speed operation and low power consumption.

When the enable input (G) is active (low), the comparator compares the two 8-bit numbers applied to inputs A1-A8 and B1-B8. The output pins (O1A-O1H) indicate the relative magnitudes of the numbers based on the subtraction result.

Detailed Application Field Plans

The 74HC688D,652 finds applications in various fields where binary or BCD number comparison is required. Some specific application areas include:

1. Arithmetic circuits: Used in digital calculators, counters, and other arithmetic units.
2. Data processing systems: Employed for data sorting, searching, and ranking operations.
3. Control circuits: Utilized in control units for decision-making based on numerical comparisons.
4. Communication systems: Integrated into protocols that involve magnitude-based comparisons.

Detailed and Complete Alternative Models

There are several alternative models available in the market that offer similar functionality to the