The 74LS12 Triple 3-Input Positive NAND Gates With Collector Outputs contains three 3 input independent gates each of which performs the positive logic NAND function. 74LS12 IC can be soldered directly to the circuit board or can be mounted on a 14 pin IC base. 74LS12 Triple 3-Input Positive NAND Gates With Collector Outputs circuit is designed such that the operation produced on the inputs of pin are (1&2&3&4 NAND 10&11&12&13) is produced on the pin 8 . Operating supply voltages to the IC can vary between 4.5V to 5V and to a maximum of 5.5V and the input logic levels to the device in ‘0’ (LOW) state is max. 0.7V and for ‘1’ (HIGH) state is min 2V.