Datasheet

SN54ACT244, SN74ACT244
OCTAL BUFFERS/DRIVERS
WITH 3-STATE OUTPUTS
SCAS517C − JUNE 1995 − REVISED OCTOBER 2002
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
switching characteristics over recommended operating free-air temperature range,
V
CC
= 5 V ± 0.5 V (unless otherwise noted) (see Figure 1)
PARAMETER
FROM TO
T
A
= 25°C SN54ACT244 SN74ACT244
UNIT
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
MIN TYP MAX MIN MAX MIN MAX
UNIT
t
PLH
A
Y
2 6.5 9 1 10 1.5 10
ns
t
PHL
A Y
2 7 9 1 10 1.5 10
ns
t
PZH
OE
Y
1.5 7 8.5 1 9.5 1 9.5
ns
t
PZL
OE
Y
2 7 9.5 1 11 1.5 10.5
ns
t
PHZ
OE
Y
2 8 9.5 1 11 1.5 10.5
ns
t
PLZ
OE
Y
2.5 7.5 10 1 11.5 2 10.5
ns
operating characteristics, V
CC
= 5 V, T
A
= 25°C
PARAMETER TEST CONDITIONS TYP UNIT
C
pd
Power dissipation capacitance per buffer/driver C
L
= 50 pF, f = 1 MHz 45 pF
PARAMETER MEASUREMENT INFORMATION
From Output
Under Test
C
L
= 50 pF
(see Note A)
LOAD CIRCUIT
S1
2 × V
CC
500 Ω
500 Ω
t
PLH
t
PHL
Output
Control
(low-level
enabling)
Output
Waveform 1
S1 at 2 × V
CC
(see Note B)
Output
Waveform 2
S1 at Open
(see Note B)
V
OL
V
OH
t
PZL
t
PZH
t
PLZ
t
PHZ
1.5 V1.5 V
1.5 V 1.5 V
≈V
CC
3 V
0 V
50% V
CC
50% V
CC
V
OH
V
OL
0 V
50% V
CC
V
OL
+ 0.3 V
50% V
CC
≈0 V
3 V
Open
Input
Output
VOLTAGE WAVEFORMS VOLTAGE WAVEFORMS
t
PLH
/t
PHL
t
PLZ
/t
PZL
t
PHZ
/t
PZH
Open
2 × V
CC
Open
TEST S1
V
OH
− 0.3 V
NOTES: A. C
L
includes probe and jig capacitance.
B. 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.
C. All input pulses are supplied by generators having the following characteristics: PRR ≤ 1 MHz, Z
O
= 50 Ω, t
r
≤ 2.5 ns, t
f
≤ 2.5 ns.
D. The outputs are measured one at a time with one input transition per measurement.
Figure 1. Load Circuit and Voltage Waveforms