ZiLOG Z80 Handbook page 268

CAPACITANCE
TA = 25°C, f = 1 MHz
Symbol
Parameter
Typ.
Max . Unit
Test Conditions
C.a
Clock Capacitance
20 pF
d Pins
U
C
IN
Input Capacitance
5
PF
nmeasure
Returned to Ground
LOUT
Output Capacitance 10 pF
VCC
Fig. A-1 . Clock driver.
I' TTL
An external clock pull-up resistor of (33012) will meet both ac and dc clock requirements.
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