74HC21 Dual 4-input AND Gate IC (7421 IC) DIP-14 Package

74HC21 is Quad 4-Input AND circuit manufactured in 14 Pin IC package. The 74HC21 provides 4 independent 2-input AND gates with standard push-pull outputs. The 74HC21 designed as an advanced high speed CMOS 2 Input AND circuit fabricated with silicon gate CMOS technology. It achieves a high−speed operation similar to equivalent Bipolar Schottky TTL while maintaining the CMOS low power dissipation. The interior circuit composed of 4 stages including buffer output, provides high noise immunity and stable output. An input protection circuit ensures that 0 V to 7 V are often applied to the input pins without reference to the supply voltage. This device often accustomed to interface 5 V to 3 V systems and two supply systems like battery backup. This circuit prevents device destruction thanks to mismatched supply and input voltages.

The 74HC21 logic family is functionally also as pin-out compatible with the quality 74LS logic family. It has an operating voltage range from 2V to 6V and consumes only 20uA of current. 74HC21 inverter IC utilizes advanced silicon-gate CMOS technology to realize operating speeds almost like LS-TTL gates with the low power consumption of ordinary CMOS integrated circuits. The 74HC21 has buffered outputs, providing high noise immunity and therefore the ability to drive 10 LS-TTL loads.  All inputs shielded from damage due to static discharge by internal diode clamps to VCC and ground. They are specified in compliance with JEDEC standard no. 7A.