74F169

INTEGRATED CIRCUITS 74F168*, 74F169 4-bit up/down binary synchronous counter * Discontinued part. Please see the Discontinued Product List in Section 1, page 21. Product specification IC15 Data Handbook 1996 Jan 05 Philips Semiconductors Philips Semiconductors Product specification 4-bit up/down binary synchronous counter 74F169 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 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. 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. This mode of operation eliminates the output spikes which are normally associated with asynchronous (ripple clock) counters. A buffered clock input triggers the flip-flops on the Low-to-High transition of the clock. The counter is fully programmable; that is, the outputs may be preset to either level. 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 ...