NXP Semiconductors
74LVC244A; 74LVCH244A
Octal buffer/line driver; 3-state
V
I
negative
pulse
0V
t
W
90 %
V
M
10 %
t
f
t
r
t
r
t
f
90 %
V
M
10 %
t
W
V
EXT
V
CC
V
I
V
O
RL
V
M
V
I
positive
pulse
0V
V
M
G
RT
DUT
CL
RL
001aae331
Test data is given in
Definitions for test circuit:
R
L
= Load resistance.
C
L
= Load capacitance including jig and probe capacitance.
R
T
= Termination resistance should be equal to output impedance Z
o
of the pulse generator.
V
EXT
= External voltage for measuring switching times.
Fig 8.
Table 9.
Test circuit for measuring switching times
Test data
Input
V
I
t
r
, t
f
≤
2.5 ns
≤
2.5 ns
≤
2.5 ns
V
CC
2.7 V
2.7 V
Load
C
L
50 pF
50 pF
50 pF
R
L
500
Ω
500
Ω
500
Ω
V
EXT
t
PLH
, t
PHL
open
open
open
t
PLZ
, t
PZL
2
×
V
CC
2
×
V
CC
2
×
V
CC
t
PHZ
, t
PZH
GND
GND
GND
Supply voltage
1.2 V
2.7 V
3.0 V to 3.6 V
[1]
The circuit performs better when R
L
= 1 kΩ.
74LVC_LVCH244A_6
© NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 06 — 13 August 2009
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