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HD74HCT449
Quad. Bus Transceivers with Individual Direction Controls
Description
The HD74HCT449 has 4 bus transceivers. The device has direction control inputs with individual. And this control inputs select data transmissible direction. When GBA is high, A outputs are disable, and when GAB is high, B outputs are disable.
Features
• • • • • • LSTTL Output Logic Level Compatibility as well as CMOS Output Compatibility High Speed Operation: tpd (A to B) = 12.5 ns typ (CL = 50 pF) High Output Current: Fanout of 15 LSTTL Loads Wide Operating Voltage: VCC = 4.5 to 5.5 V Low Input Current: 1 µA max Low Quiescent Supply Current: ICC (static) = 4 µA max (Ta = 25°C)
Function Table
Enable GBA H X L X H H : L : X : High Level Low Level Irrelevant.