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HD74BC620A Datasheet, PDF (6/9 Pages) Hitachi Semiconductor – Octal Bus Transceivers With 3 State Outputs
HD74BC620A
Test Circuit
VCC
Input
Pulse
Generator
Zout = 50 Ω
VCC
GBA
GAB
A1 S1
B1
Output
CL =
50 pF
500 Ω
450 Ω
50 Ω
Scope
OPEN *4
7V
Notes:
1. CL includes probe and jig capacitance.
2. A2-B2 to A8-B8 are identical to above load circuit.
3. S1: Input-Output change switch.
4. Open: tPLH, tPHL, tZH tHZ
7 V: tZL, tLZ
Waveforms-1
tf
tr
Input
90 %
1.5 V
10 %
tPLH
90 %
3V
1.5 V
10 %
0V
tPHL
Output
VOH
1.5 V
1.5 V
VOL
6