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HD74BC620A Datasheet, PDF (1/9 Pages) Hitachi Semiconductor – Octal Bus Transceivers With 3 State Outputs
HD74BC620A
Octal Bus Transceivers With 3 State Outputs
ADE-205-024 (Z)
Rev. 0
June 1993
Description
The HD74BC620A provides high drivability and operation equal to or better than high speed bipolar
standard logic IC by using Bi-CMOS process. The device features low power dissipation that is about 1/5
of high speed bipolar logic IC. When the frequency is 10 MHz. The device has eight bus transceivers with
three state outputs in a 20 pin package. This device allows data transmission from the A bus to the B bus or
from the B bus to the A bus depending upon the logic levels at the enable inputs (GBA and GAB). The
enable inputs can be used to disable the device so that the buses are effectively isolated.
Features
• Input/Output are at high impedance state when power supply is off.
• Input pins can be open, when not used, owing to built in input pull up circuit.
• Input is TTL level.
• Wide operating temperature range
Ta = –40 to +85°C.
Function Table
Enable Inputs
GBA
L
H
H
L
H : High level
L : Low level
GAB
L
H
L
H
Operation
B data to A bus
A data to B bus
Isolation
B data to A bus
A data to B bus