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DM74LS90 Decade and Binary Counters
August 1986 Revised March 2000
DM74LS90 Decade and Binary Counters
General Description
Each of these monolithic counters contains four masterslave flip-flops and additional gating to provide a divide-bytwo counter and a three-stage binary counter for which the count cycle length is divide-by-five for the DM74LS90. All of these counters have a gated zero reset and the DM74LS90 also has gated set-to-nine inputs for use in BCD nine’s complement applications. To use their maximum count length (decade or four bit binary), the B input is connected to the QA output. The input count pulses are applied to input A and the outputs are as described in the appropriate truth table.
DM74LS90 Datasheet
