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. Devices also available in Tape and Reel.
74LS Datasheet pdf – Synchronous 4-Bit Binary Counters – Fairchild Semiconductor
The carry look-ahead circuitry provides for cascading. The function of the counter whether enabled, dis. These counters are fully programmable; that is, the outputs. These counters are fully programmable; that is, the outputs may be preset to either level. Synchronous 4-Bit Binary Counters.
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. Fairchild Semiconductor Electronic Components Datasheet. Order Number Package Number. These counters feature a fully independent clock circuit.
View Datasheet for Mobile. Synchronous operation is pro.
The clear function for the. 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 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.
Changes made to control inputs enable P or T or load that will modify the operating mode have no effect until clocking occurs.
74LS Datasheet PDF –
The carry output is decoded by means of. 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.
The gate output is connected to the clear input to synchronously clear the counter to all low outputs. The carry output is decoded by means of a NOR gate, thus preventing spikes during the normal counting mode of operation. A buffered clock input triggers the four flip-flops on the rising positive-going edge of the clock input waveform.
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 are two count-enable inputs and a ripple carry output. 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.
The carry look-ahead circuitry provides for cascading counters for n-bit synchronous applications without addi- tional gating.
Changes made to control inputs enable P or T or load that. The ripple carry output thus enabled will produce a high. Instrumental in accomplishing this function. This high-level over- flow ripple carry pulse can be used to enable successive dtaasheet stages.
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 output 14 ns s Typical clock frequency 32 MHz s Typical power dissipation 93 mW Ordering Code: This mode of operation eliminates the output counting spikes which are normally associated with asynchronous ripple clock counters.
A buffered clock input triggers the. 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.
DM74LSA is synchronous; and a low level at the clear. This synchronous clear allows the count length to. This mode of operation eliminates the output counting. These synchronous, presettable counters feature an inter. The gate output is connected to the clear input to.