The 74ACT520 SJX is an advanced octal comparator, typically used in digital systems. It is a high speed, low power quad dual-in-line package comprising eight comparators.

Application Field:

The 74ACT520 SJX is ideal for digital systems requiring reference and compare functions. The comparators with Schmitt trigger inputs and low active-output levels permit direct interfacing to TTL, as well as other logic circuitry. Applications include A/D converters, digital thermometers, and chipsets with parallel digital interface data buses, such as SDRAM, SRAM and DRAM.

Working Principle:

The 74ACT520SJX has four identical comparators with dual-in-line packages. The differential inputs of the comparator can accept signals with voltages anywhere from 0 to 5V. When two signals are given to the differential inputs, the comparator compares the two signals and gives the output according to the comparison. If the two input signals are same, the output is low, and if the two signals are different, the output is high.

The output of the comparator is subjected to a de-bouncing circuitry which removes any transient noise in the output and gives a steady level output. The comparator also has additional features such as Hysteresis (Schmitt Trigger) which allows the comparator to give an output depending on the hysteresis level. Thus if the input level crosses the hysteric level, the output will change its state.

The Supply Voltage VCC required to drive these comparators varies from 3V to 5.5V, and the Operating temperature varies from -55°C to +125°C. The Frequency Response of the comparator is also very high up to 50 MHz. The propagation delay time of the comparator is less than 10ns, which makes it ideal for faster changing logic systems.

The 74ACT520SJX is available in QSOP, DIP and SOJD packaging depending on the requirement. These packages are suitable for surface mount, through-hole, as well as plastic encapsulated technology. Depending on the need, the packages with different pin counts can also be provided.

Conclusion

The 74ACT520SJX is an advanced octal comparator that is ideal for digital system designs requiring Fast Comparative switching inputs. The wide operating voltage range and small package size are suitable for environments where space and power are an issue. The high frequency response and low propagation delay time ensure performance in high speed digital systems.