MM74HC243N ,Inverting Quad TRI-STATE TransceiverMM54HC242/MM74HC242InvertingQuadTRI-STATETransceiverMM54HC243/MM74HC243QuadTRI-STATETransceiverJanu ..
MM74HC244 ,Octal TRI-STATE(RM) BufferMM54HC244/MM74HC244OctalTRI-STATEBufferJanuary1988MM54HC244/MM74HC244OctalTRI-STATEÉBufferGeneralDe ..
MM74HC244MTC ,Octal 3-STATE BufferFeaturesThe MM74HC244 is a non-inverting buffer and has two
MM74HC243N
Inverting Quad TRI-STATE Transceiver
TL/L/5019
MM54HC242/MM74HC242
Inverting
Quad
TRI-STATE
Transceiver
MM54HC243/MM74HC243
Quad
TRI-STATE
Transceiver
January 1988
MM54HC242/MM74HC242
Inverting Quad TRI-STATEÉ Transceiver
MM54HC243/MM74HC243 Quad TRI-STATE Transceiver
General Description
These TRI-STATE bidirectional invertingand non-inverting
buffers utilize advanced silicon-gate CMOS technologyand
are intendedfor two-way asynchronous communicationbe-
tween data buses. They have high drive current outputs
which enable high speed operation when driving largebus
capacitances. These circuits possessthelow power dissi-
pation and high noise immunity associated with CMOScir-
cuits,but speeds comparabletolow power Schottky TTL
circuits. Theycan also drive15 LS-TTL loads.
The MM54HC243/MM74HC243isa non-inverting buffer
andthe MM54HC242/MM74HC242isan inverting buffer.
Each devicehas one active high enable (GBA),and one
activelow enable (GAB). GBA enablestheA outputsand
GAB enablestheB outputs. This device doesnot have
Schmitt trigger inputs.
All inputsare protected from damage dueto static dis-
chargeby diodesto VCCand ground.
Features Typical propagation delay:12ns TRI-STATE outputs Twoway asynchronous communication High output current:6mA (74HC) Wide power supply range: 2–6V Low quiescent supply current:80mA (74HC)
Connection Diagrams
Dual-In-Line Package
TL/L/5019–1
Top View
Order Number MM54HC242or MM74HC242
Dual-In-Line Package
TL/L/5019–2
TopView
Order Number MM54HC243or MM74HC243
Truth Tables
’HC242
Control Inputs Data Port Status
GAB GBA A B H OUTPUT Input H Isolated Isolated L Isolated Isolated L Input OUTPUT
’HC243
Control Inputs Data Port Status
GAB GBA A B H OUTPUT Input H Isolated Isolated L Isolated Isolated L Input OUTPUT
TRI-STATEÉ isaregistered trademarkof National SemiconductorCorp.
C1995National SemiconductorCorporation RRD-B30M115/PrintedinU.S.A.
