74ACT646 ,Octal Bus Transceiver and Register with TRI-STATE Outputs54AC/74AC646 74ACT646#OctalTransceiver/RegisterwithTRI-STATEOutputsMarch199354AC/74AC646 74ACT646#O ..
74ACT646SPC , Octal Bus Transceiver/Register with 3-STATE Outputs74AC646 • 74ACT646 Octal Transceiver/Register with 3-STATE OutputsNovember 1988Revised December 199 ..
74ACT652 ,Transceiver/RegisterFeaturesThe ACT652 consists of bus transceiver circuits with D-
74AC646-74ACT646
Octal Bus Transceiver and Register with TRI-STATE Outputs
TL/F/10132
54AC/74AC646
74ACT646
Octal
Transceiver/Register
with
TRI-STATE
Outputs
March 1993
54AC/74AC646# 74ACT646
Octal Transceiver/Register with TRI-STATEÉ Outputs
General Description
The ’AC/’ACT646 consistof registeredbus transceivercir-
cuits, with outputs, D-type flip-flopsand control circuitrypro-
viding multiplexed transmissionof data directly fromthein-
putbusor fromthe internal storage registers. DataontheABbuswillbe loadedintothe respective registersonthe
LOW-to-HIGH transitionofthe appropriate clockpin (CPAB CPBA). The four fundamental data handling functions
availableare illustratedin Figures 1-4.
Features Independent registersforAandB buses Multiplexed real-time and stored data transfers TRI-STATE outputs 300mil slim dual-in-line package Outputs source/sink24mA ’ACT646has TTL compatible inputs Standard Military Drawing (SMD) ’AC646: 5962-89682
Logic Symbols
TL/F/10132–1
IEEE/IEC
TL/F/10132–2
Connection Diagrams
Pin Assignment
forDIP, Flatpakand SOIC
TL/F/10132–3
Pin Assignment
forLCCand PCC
TL/F/10132–4
PinNames Description
A0–A7 Data Register AInputs
Data Register AOutputs
B0–B7 Data Register BInputs
Data Register BOutputs
CPAB, CPBA Clock Pulse Inputs
SAB, SBA Transmit/ReceiveInputs OutputEnable Input
DIR Direction ControlInput
TRI-STATEÉ isaregistered trademarkof National SemiconductorCorporation.
FACTTMisa trademarkof NationalSemiconductor Corporation.
C1995National SemiconductorCorporation RRD-B30M75/PrintedinU.S.A.
