These synchronous presettable counters feature an inter- nal carry look-ahead for application in high-speed counting designs The LSA and LSA are. SN74LSADR. SOIC. D. Q1. SN74LSANSR. SO. NS. Q1. Texas Instruments 74LS Counter ICs are available at Mouser Electronics. Mouser offers inventory, pricing, & datasheets for Texas Instruments 74LS
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As presetting is synchronous. The clear function for the DM74LSA is synchronous; and a low level at the clear inputs sets all four of the flip-flop outputs LOW after the next clock pulse, regardless of the levels of the enable inputs.
These synchronous, datadheet counters feature an inter. DM74LSA is synchronous; and a low level at the clear.
National Semiconductor – datasheet pdf
The carry output is decoded by 74ls16 of a NOR gate, thus preventing spikes during the normal counting mode of operation.
The clear function for the. These counters are fully programmable; that is, the outputs may be vatasheet to either level. Fairchild Semiconductor Electronic Components Datasheet. The ripple carry output thus enabled will produce a high. This synchronous clear allows the count length to be modified easily, as decoding the maximum count desired can be accomplished with one external NAND gate.
The gate output is connected to the clear input to synchronously clear the counter to all low outputs. A buffered clock input triggers the. View PDF for Mobile. This mode of operation eliminates the output counting.
Instrumental in accomplishing this function are two count-enable inputs and a ripple carry output. This synchronous clear allows the count length to. Order Number Package Number.
The ripple carry output thus enabled will produce a high- level output pulse with a duration approximately equal to the high-level portion of the Q A output. Instrumental in accomplishing this function. This high-level over- flow ripple carry pulse can be used to enable successive cascaded stages.
These counters feature a fully independent clock circuit. Devices also available in Tape and Reel.
74LS Datasheet(PDF) – TI store
A buffered clock input triggers the four flip-flops on the rising positive-going edge of the clock input waveform.
Features s Synchronously programmable s Internal look-ahead for fast counting s Carry output for n-bit cascading s Synchronous counting s Load control line s Diode-clamped inputs s Typical propagation time, clock to Q datasyeet 14 ns s Typical clock frequency 32 MHz s Typical power dissipation 93 mW Ordering Code: The carry look-ahead circuitry provides for cascading.
The carry look-ahead circuitry provides for cascading counters for n-bit synchronous applications without addi- tional gating. The function of the counter whether enabled, dis. The function of the counter whether enabled, dis- abled, loading, or counting will be dictated solely by the conditions meeting the stable set-up and hold times. The clear function for the DM74LSA is asynchro- nous; and a low level at the clear input sets all four of the flip-flop outputs LOW, regardless of the levels of clock, load, or enable inputs.
These counters are fully programmable; that is, the outputs. Synchronous operation is pro. Changes made to control inputs enable P or T or load that. Synchronous operation is pro- vided 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.
Changes made to control inputs enable P or T or load that will modify the operating mode have no effect until clocking occurs. Synchronous 4-Bit Binary Counters. 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 input.
The 74l1s63 output is decoded by means of. The gate output is connected to the clear catasheet to. This mode of operation eliminates the output counting spikes which are normally associated with asynchronous ripple clock counters.