The 74HC273D is identical in pinout to the LS/ALS273. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALSTTL outputs.
The 74HC373D is a high-speed Si-gate CMOS device and is pin compatible with Low-power Schottky TTL. It is specified in compliance with JEDEC standard no. 7A
The 74HC541D 3-STATE buffers uti-lize advanced silicon-gate CMOS technology. They pos-sess high drive current outputs which enable high speed operation even when driving large bus capacitances.
74HC/HCT573 是一个带三态输出的8位D型锁存器。该器件具有锁存使能(LE)和输出使能(OE)。当 LE为高电平时，输入端的数据进入锁存器中。在这种情况下，锁存器是透明的，每次其相应的D输入更改时，锁存器输出都会更改。当LE为低电平时，锁存器存储LE 下降沿前一个建立时间的输入端信息。0E上的高电平使输出呈现高阻态。0E输入的运行不会影响锁存器的状态。输入内置钳位二极管。这样就可以使用限流电阻将输入接口连接到超过VCC的电压。
