1 Features
• Typical propagation delay (A to B, B to A) of 7ns at
VCC = 5 V, CL = 15pF, TA = 25oC
• Three-state outputs
• Buffered inputs
• Fanout (over temperature range)
– Standard outputs : 10 LSTTL loads
– Bus driver outputs : 15 LSTTL loads
• Wide operating temperature range : -55oC to
125oC
• Balanced propagation delay and transition times
• Significant power reduction compared to LSTTL
logic ICs
• HC types
– 2 V to 6 V Operation
– High noise immunity: NIL = 30%, NIH = 30% of
VCC at VCC = 5V
• HCT types
– 4.5 V to 5.5 V operation
– Direct LSTTL input logic compatibility, VIL= 0.8
V (Max), VIH = 2 V (Min)
– CMOS input compatibility, Il ≤ 1μA at VOL, VOH

2 Description
The CDx4HC243 and CDx4HCT243 are quad bus
transceivers with 3-state outputs. The OEA and OEB
inputs control both the high-impedance state as well
as the direction of communication through the device.