Datasheet

74HC21_5 © NXP B.V. 2009. All rights reserved.
Product data sheet Rev. 05 — 7 May 2009 7 of 14
NXP Semiconductors
74HC21
Dual 4-input AND gate
Test data is given in Table 9.
Definitions test circuit:
R
T
= termination resistance should be equal to output impedance Z
o
of the pulse generator.
C
L
= load capacitance including jig and probe capacitance.
Fig 8. Test circuit for measuring switching times
001aah768
t
W
t
W
t
r
t
r
t
f
V
M
V
I
negative
pulse
GND
V
I
positive
pulse
GND
10 %
90 %
90 %
10 %
V
M
V
M
V
M
t
f
V
CC
DUT
R
T
V
I
V
O
C
L
G
Table 9. Test data
Type Input Load Test
V
I
t
r
, t
f
C
L
74HC21 V
CC
6.0 ns 15 pF, 50 pF t
PLH
, t
PHL