UT54ACS191E Datasheet | Aeroflex Circuit Technology

FEATURES - Single down/up count control line - Look-ahead circuitry enhances speed of cascaded counters - Fully synchronous in count modes - Asynchronously pre-settable with load control - 0.6μm CRH CMOS process - Latchup immune - High speed - Low power consumption - Wide power supply operating range of 3.0V to 5.5V - Available QML Q or V processes - 16-lead flatpack - UT54ACS191E - SMD 5962-96564 DESCRIPTION The UT54ACS191E is a performance and voltage enhanced version of the UT54ACS191 synchronous 4-bit, reversible updown binary counter. Synchronous counting operation is provided by having all flip-flops clocked simultaneously so that the outputs change coincident with each other when so instructed. Synchronous operation eliminates the output counting spikes associated with asynchronous counters. The outputs of the four flip-flops are triggered on a low-to-highlevel transition of the clock input if the enable input (CTEN) is low. A logic one applied to CTEN inhibits counting. The direction of the count is determined by the level of the down/up (D/ U) input. When D/U is low, the counter counts up and when D/ U is high, it counts down. The counter features a fully independant clock circuit. Changes at control inputs (CTEN and D/U) that will modify the operating mode have no effect on the contents of the counter until clocking occcurs. The counter is fully programmable. The outputs may be preset to either logic level by placing a low on the load input and entering the desired data at the data inputs. The output will change to agree with the data inputs independently of the level of the clock input. The asynchronous load allows counters to be used as modulo-N dividers by simply modifying the count length with the preset inputs. Two outputs have been made available to perform the cascading function: ripple clock and maximum/minimum (MAX/MIN) count. The MAX/MIN output produces a high-level output pulse with a duration approximately equal to one plete cycle of the...