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                       74LS161              4-BIT SYNCHRONOUS COUNTER                                  



74LS161 Circuit Diagram and Pinouts

with Asynchronous Clear mode

The 74161 IC package contains a single 4 bit synchronous counter circuit with a user controllable CLR function (pin 1). Unlike the 74163, the clear is asynchronous, or in other words, it takes place immediately, regardless of the status of the clock input. Multiple units can be cascaded to form larger registering synchronous counters.

This counter IC can be preloaded to start at any value (decimal 0-15, binary 0000-1111). Once load sequence is complete, clock impulses received on the CLK pin will perform a counting operation and will be represented on QA, QB, QC, and QD.

Applications include, digital counters, frequency counters, digital clocks, program counters, memory addressors, and others where high performance, glitch-free, counting is required.

This part is readily available from many electronics suppliers in various packages and pinouts. Check with exact datasheet to ensure correct wiring, the information provided is for explanatory uses only.

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