Texas Instruments 54HC191
The ’HC191 devices are 4-bit synchronous, reversible, up/down binary counters. This mode of operation eliminates the output counting spikes normally associated with asynchronous (ripple-clock) counters.| Part No. | 54HC191 |
|---|---|
| Datasheet | 54HC191 Download |
| Manufacturer |  Texas Instruments |
| Description | 4-BIT SYNCHRONOUS UP/DOWN BINARY COUNTERS |
| Buy | Stock & Price |
SN54HC191, SN74HC191 4ĆBIT SYNCHRONOUS UP/DOWN BINARY COUNTERS D Wide Operating Voltage Range of 2 V to 6 V D Outputs Can Drive Up To 10 LSTTL Loads D Low Power Consumption, 80-µA Max ICC D Typical tpd = 13 ns D ±4-mA Output Drive at 5 V D Low Input Current of 1 µA Max D Single Down/Up Count-Control Line D Look-Ahead Circuitry Enhances Speed of Cascaded Counters D Fully Synchronous in Count Modes D Asynchronously Presettable With Load Control description/ordering information Synchronous counting operation is provided by having all flip-flops clocked simultaneously so that the outputs change coincident with each other when instructed by the steering logic. The outputs of the four flip-flops are triggered on a low- to high-level transition of the clock (CLK) input if the count-enable (CTEN) input is low. A high at 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.
