SN54/74LS is an UP/DOWN MODULO Binary Counter. Separate. Count Up and Count Down Clocks are used and in either counting mode the. 74LS datasheet, 74LS pdf, 74LS data sheet, datasheet, data sheet, pdf, Fairchild Semiconductor, Synchronous 4-Bit Binary Counter with Dual Clock. This circuit is a synchronous up down 4-bit binary counter. Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs.
The counters can then be easily cascaded by feeding the. This feature allows the counters to be used as modulo-N dividers by simply modi- fying the count length with the preset inputs. This mode of operation eliminates the output counting. The direction of counting is determined by which. The borrow output produces a pulse equal in.
The clear, count, and load inputs are buffered to lower the drive requirements of clock drivers, etc. The counter is fully programmable; that is, each output may.
Similarly, the carry output produces a pulse equal in datawheet to the count down input when an overflow condition exists. These counters were designed to be cascaded without the.
The output will change independently of the count pulses. Fairchild Semiconductor Electronic Components Datasheet.
The direction of counting is determined by which count input is pulsed while the other count input is held HIGH. Both borrow and carry outputs are available to cascade both the up and down counting functions. The counters can then be easily cascaded by feeding the borrow and carry outputs to the count down and count up inputs respectively of the succeeding counter. Synchronous operation is provided by hav. The outputs of the four master-slave flip-flops are triggered.
A clear input has been provided which, when taken to a high level, forces all outputs to the low level; independent of the count and load inputs. The counter is fully programmable; that is, each output may be preset to either level by entering the desired data at datashest inputs while the load input is LOW. These counters were designed to be cascaded without the need for external circuitry. This mode of operation eliminates the output counting spikes normally associated with asynchronous ripple- clock counters.
Synchronous operation is provided by hav- ing all flip-flops clocked simultaneously, so that the outputs change together when so instructed by the steering logic.