NXP Semiconductors 74F169
The 74F169 is a 4-bit synchronous, presettable Modulo 16 up/down counter featuring an internal carry look-ahead for applications in high-speed counting designs. This mode of operation eliminates the output spikes which are normally associated with asynchronous (ripple clock) counters. The counter is fully programmable; that is, the outputs may be preset to either level.| Part No. | 74F169 |
|---|---|
| Datasheet | 74F169 Download |
| Manufacturer |  NXP Semiconductors |
| Description | 4-bit up/down binary synchronous counter |
| Buy | Stock & Price |
FEATURES
● Synchronous counting and loading● Up/Down counting
● Modulo 16 binary counter
● Two Count Enable inputs for n-bit cascading
● Positive edge-triggered clock
● Built-in carry look-ahead capability
● Presettable for programmable operation
DESCRIPTION
Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs change coincident with each other when instructed by the Count Enable inputs and internal gating. A buffered clock input triggers the flip-flops on the Low-to-High transition of the clock. Presetting is synchronous with the clock and takes place regardless of the levels of the Count Enable inputs. A Low level on the Parallel Enable (PE) input disables the counter and causes the data at the Dn input to be loaded into the counter on the next Low-to-High transition of the clock. The direction of counting is controlled by the Up/Down (U/D) input; a High will cause the count to increase, a Low will cause the count to decrease. The carry look-ahead circuitry provides for n-bit synchronous applications without additional gating.
