Part Number : DM74LS191N
Function : Synchronous 4-Bit Binary Counter
Package : DIP 16 Pin Type
Maker : Fairchild Semiconductor
Pinouts : 
Description :
The DM74LS191N, DM74LS191 circuit is a synchronous, reversible, up/down counter. Synchronous operation is provided by having all flip-flops clocked simultaneously, so that the outputs change simultaneously when so instructed by the steering logic. This mode of operation eliminates the output count ing spikes normally associated with asynchronous (ripple clock) counters.
Block Diagram
Features
1. Counts 8-4-2-1 BCD or binary
2. Single down/up count control line
3. Count enable control input
4. Ripple clock output for cascading
5. Asynchronously presettable with load control
Datasheet PDF Download : 
Others datasheet of same file :
74LS191, 74LS191M, 74191N, DM74LS191, DM74LS191M
