Datasheet

t
PHZ
t
PLZ
t
PZL
t
PZH
3 V
0 V
Output
Control
(low-level
enabling)
Waveform 1
(see Notes C
and D)
Waveform 2
(see Notes C
and D)
≈1.5 V
V
OH
− 0.5 V
V
OL
+ 0.5 V
≈1.5 V
1.5 V 1.5 V
1.5 V
1.5 V
V
OH
V
OL
10
SN54LS240 , SN54LS241 , SN54LS244 , SN54S240 , SN54S241 , SN54S244
SN74LS240 , SN74LS241 , SN74LS244 , SN74S240 , SN74S241 , SN74S244
SDLS144D –APRIL 1985–REVISED OCTOBER 2016 www.ti.com
Product Folder Links: SN54LS240 SN54LS241 SN54LS244 SN54S240 SN54S241 SN54S244 SN74LS240
SN74LS241 SN74LS244 SN74S240 SN74S241 SN74S244
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A. C
L
includes probe and jig capacitance.
B. All diodes are 1N3064 or equivalent.
C. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output
control. Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the
output control.
D. S1 and S2 are closed for t
PLH
, t
PHL
, t
PHZ
, and t
PLZ
; S1 is open and S2 is closed for t
PZH
; S1 is closed and S2 is open
for t
PZL
.
E. All input pulses are supplied by generators having the following characteristics: PRR ≤ 1 MHz, Z
O
is approximately
50 Ω; t
r
and t
f
≤ 7 ns for SN54LS24x and SN74LS24x devices, and t
r
and t
f
≤ 2.5 ns for SN54S24x and SN74S24x
devices.
F. The outputs are measured one at a time with one input transition per measurement.
Figure 15. Voltage Waveforms,
Enable and Disable Times, 3-State Outputs