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MC74HC393
Dual 4−Stage Binary Ripple Counter
High−Performance Silicon−Gate CMOS
The MC54/74HC393 is identical in pinout to the LS393. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LSTTL outputs.
This device consists of two independent 4−bit binary ripple counters with parallel outputs from each counter stage. A ÷ 256 counter can be obtained by cascading the two binary counters.
Internal flip−flops are triggered by high−to−low transitions of the clock input. Reset for the counters is asynchronous and active−high. State changes of the Q outputs do not occur simultaneously because of internal ripple delays.