SYNCHRONOUS 4-BIT DECADE AND BINARY COUNTERS

These synchronous, presettable Counters feature an internal carry look-ahead for application in high-speed counting designs. The ALS160B, ALS162B, AS160, and AS162 are decade Counters and the ALS161B, ALS163B, AS161 and AS163 are 4-bit binary Counters Synchro- nous operation is provided by having all Flip-Flops clocked simultaneously so that the outputs change coincident with each other when so instructed by the count-enable inputs and internal gating. This mode of operation eliminates the output counting spikes that are normally asso- ciated with asynchronous (ripple clock) Counters A buffered Clock input triggers the four Flip-Flops on the rising (positive-going) edge of the Clock input waveform. These Counters are fully programmable; that is, they may be preset to any number between 0 and 9, or 15. As presetting is synchronous, setting up a low level at the load input disables the Counter and causes the outputs to agree with the setup data after the next Clock pulse regardless of the levels of the enable inputs. The clear function for the ALS160B, ALS161B, AS160, and AS161 is asynchronous and a low level at the clear input sets all four of the Flip-Flop outputs low regardless of the levels of the Clock load, or enable inputs. This synchronous clear allows the count length to be modified easily by decoding the Q outputs for the maximum count desired. The active-low output of the Gate used for decoding is connected to the clear input to synchronously clear the Counter to 0000 (LLLL). The carry look-ahead circuitry provides for cascading Counters for n-bit synchronous applications without additional gating. Instrumental in accomplishing this function are two count-enable inputs and a ripple carry output. Both count-enable inputs (ENP and ENT) must be high to count, and ENT is fed forward to enable the ripple carry output. The ripple carry output (RCO) thus enabled will produce a high-level pulse while the count is maximum (9 or 15 with QA high). This high-level overflow ripple carry pulse CAN be used to enable successive cascaded stages. Transitions at the ENP or ENT are allowed regardless of the level of the Clock input. These Counters feature a fully independent Clock circuit. Changes at control inputs (ENP, ENT, or LOAD) that will modify the operating mode have no effect on the contents of the Counter until clocking occurs. The function of the Counter (whether enabled, disabled, loading, or counting) will be dictated solely by the conditions meeting the stable setup and hold times. The SN54ALS160B through SN54ALS163B and SN54AS160 through SN54AS163 are characterized for operation over the full military temperature range of 55C to 125C. The SN74ALS160B through SN74ALS163B and SN74AS160 through SN74AS163 are characterized for operation from 0C to 70C By Texas Instruments
SN74ALS160B 's PackagesSN74ALS160B 's pdf datasheet
SN54ALS160B
SN54ALS163B
SN54AS160
SN74AS160
SN54AS163




SN74ALS160B Pinout, Pinouts
SN74ALS160B pinout,Pin out
This is one package pinout of SN74ALS160B,If you need more pinouts please download SN74ALS160B's pdf datasheet.

SN74ALS160B Application circuits
SN74ALS160B circuits
This is one application circuit of SN74ALS160B,If you need more circuits,please download SN74ALS160B's pdf datasheet.


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