标签: 74ls168

74LS168.pdf54LS168SynchronousBi-DirectionalBCDDecadeCounterJune198954LS168SynchronousBi-DirectionalBCDDecadeCounterGeneralDescriptionThe54LS168isafullysynchronous4-stateupdowncoun-terfeaturingapresetcapabilityforprogrammableoperationcarrylookaheadforeasycascadingandaUDinputtocon-trolthedirectionofcountingItcountsintheBCD(8421)sequenceandallstatechangeswhetherincountingorpar-allelloadingareinitiatedbytheLOW-to-HIGHtransitionoftheclock……