HD74BC645A Datasheet, PDF (6/9 Pages) Hitachi Semiconductor – Octal Bus Transceivers With 3 State Outputs

HD74BC645A
Test Circuit
V_CC
Input
Pulse
Generator
Zout = 50 Ω
V_CC
G
A1 ^S1
B1
Output
C_L =
50 pF
500 Ω
450 Ω
50 Ω
Scope
DIR
OPEN ^*4
7V
Notes:
1. C_L 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: t_PLH, t_PHL, t_ZH t_HZ
7 V: t_ZL, t_LZ
Waveforms-1
Input
Output
10 %
t_r
90 %
1.5 V
t_PLH
1.5 V
t_f
90 %
1.5 V
10 %
t_PHL
1.5 V
3V
0V
V_OH
V_OL
6