The TTL family uses the NAND gate, the ECL family uses the NOR gate and the CMOS family uses the inverter.

• 晶体管一晶体管逻辑电路元件应用nand栅门，发射极耦合逻辑电路元件应用nor栅门，补充金属氧化物半导体元件使用变极器。