74LS21 DUAL 4-INPUT AND GATE in Pakistan

This circuit is a synchronous up/down 4-bit binary counter. Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs change together when so instructed by the steering logic. This mode of operation eliminates the output counting spikes normally associated with asynchronous (ripple clock) counters. The outputs of the four master-slave flip-flops are triggered by a low-to-high level transition of either count (clock) input. The direction of counting is determined by which count input is pulsed while the other count input is held high. The counter is fully programmable; that is, each output may be preset to either level by entering the desired data at the inputs while the load input is low. The output will change independently of the count pulses.

SN74LS86N 74HS86 SN74LS 7486N 7486 Quad Exclusive-OR Gate in Pakistan

The NAND GATES IC 74HC00 Nand IC 7400 74LS00 provides four independent 2-input NAND gates with standard push-pull outputs. The device is designed for operation with a power supply range of 2.0V to 6.0V.