74ABT657_3 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2010. All rights reserved.
Product data sheet Rev. 03 — 15 March 2010 10 of 17
NXP Semiconductors
74ABT657
Octal transceiver with parity generator/checker; 3-state
V
M
= 1.5 V
Fig 8. 3-state output enable time to LOW-level and output disable time from LOW-level
001aae832
V
M
V
M
V
OL
+ 0.3 V
V
M
V
I
GND
t
PLZ
t
PZL
OE
An, Bn,
PARITY,
ERROR
V
OL
3.5 V
a. Input pulse definition b. Test circuit
Test data and V
EXT
levels are given in Table 8.
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
= Test voltage for switching times.
Fig 9. Test circuit for measuring switching times
001aai298
V
M
V
M
t
W
t
W
10 %
90 % 90 %
0 V
V
I
V
I
negative
pulse
positive
pulse
0 V
V
M
V
M
90 %
10 %
90 %
10 % 10 %
t
f
t
r
t
r
t
f
V
EXT
V
CC
V
I
V
O
mna616
DUT
C
L
R
T
R
L
R
L
G
Table 8. Test data
Input Load V
EXT
V
I
f
I
t
W
t
r
, t
f
C
L
R
L
t
PHL
, t
PLH
t
PZH
, t
PHZ
t
PZL
, t
PLZ
3.0 V 1 MHz 500 ns ≤ 2.5 ns 50 pF 500 Ω open open 7.0 V
