SN74ALS520DWR

Overview

The SN74ALS520DWR is an 8-bit, field-programmable, comparator device integrated with two high-speed drivers and two D-type flip-flops. The 8-bit register provides cascade capability to expand the number of bits in a register from 8 to 16. It also allows for simultaneous read and write operations. The device also incorporates a strobe input (STRB) to latch the 8-bit data from the comparator port.

The device has a single 5V-powered supply and low-power Schottky TTL compatible inputs with 5µA static current. The device consumes 17µA static current and has a small 3V-5V input power range, which makes it suitable for battery-powered applications. The SN74ALS520DWR is available in space-saving 20- and 24-pin, hermetic, surface-mount packages.

Applications:

The SN74ALS520DWR is primarily used in logic and signal buffering applications, where a reliable comparison between two logic values is required. Examples include signal conditioning and timing circuits, such as those used in interfacing computers and microprocessors.

This device is also commonly used in 8-bit digital-to-analog converters, 8-bit analog-to-digital converters, clock and data synchronization logic, and data bus systems. Additionally, it is useful as an address Decoder, instruction Decoder, and shift Register in various embedded controller applications.

Working Principle

The SN74ALS520DWR operates by comparing the voltage on two input pins (A and B) and driving their respective outputs logic H (\'1\') or logic L (\'0\'). The output will be logic HIGH if A is higher than B and logic LOW if A is lower than B. The voltage thresholds of the comparator can be adjusted by varying the supply voltage or by adding external resistors.

The SN74ALS520DWR includes two 8-bit registers. The data input is compared against the data stored in the register. If a comparator detects the difference between the data in the register and the data input, the output of the comparator is latched into the register. The stored data is then available through the 8-bit parallel data output.

In addition, the SN74ALS520DWR also integrates two high-speed drivers, allowing for a fast response to input logic transitions. The loaded output can drive circuits with higher voltage requirements. The device also includes a strobe pin, making it possible for the device to be triggered with a single external signal.

Conclusion

The SN74ALS520DWR is a high-speed, low-power Schottky chip commonly used in a variety of logic and signal buffering applications, such as address Decoders, instruction Decoders, clock and data synchronization circuits, shift Registers, and various embedded-controller applications. The device is designed with two 8-bit registers that compare input data with data stored in the register to detect changes, two high-speed drivers for fast response, and a strobe pin for external triggering.