74LS190

PRESETTABLE BCD/DECADE UP/DOWN COUNTERS PRESETTABLE 4-BIT BINARY UP/DOWN COUNTERS The SN54 / 74LS190 is a synchronous UP/ DOWN BCD Decade (8421) Counter and the SN54/ 74LS191 is a synchronous UP / DOWN Modulo-16 Binary Counter. State changes of the counters are synchronous with the LOW-to-HIGH transition of the Clock Pulse input. An asynchronous Parallel Load (PL) input overrides counting and loads the data present on the Pn inputs into the flip-flops, which makes it possible to use the circuits as programmable counters. A Count Enable (CE) input serves as the carry / borrow input in multi-stage counters. An Up / Down Count Control (U/D) input determines whether a circuit counts up or down. A Terminal Count (TC) output and a Ripple Clock (RC) output provide overflow/underflow indication and make possible a variety of methods for generating carry / borrow signals in multistage counter applications. SN54/74LS190 SN54/74LS191 PRESETTABLE BCD/ DECADE UP/ DOWN COUNTERS PRESETTABLE 4-BIT BINARY UP/ DOWN COUNTERS LOW POWER SCHOTTKY J SUFFIX CERAMIC CASE 620-09 16 1 Low Power . . . 90 mW Typical Dissipation High Speed . . . 25 MHz Typical Count Frequency Synchronous Counting Asynchronous Parallel Load Individual Preset Inputs Count Enable and Up/ Down Control Inputs Cascadable Input Clamp Diodes Limit High Speed Termination Effects CONNECTION DIAGRAM DIP (TOP VIEW) V CC 16 P 0 15 CP 14 RC 13 TC 12 PL 11 P 2 10 P 3 9 16 1 N SUFFIX PLASTIC CASE 648-08 16 1 D SU...