Datasheet
SN54AHCT123A, SN74AHCT123A
DUAL RETRIGGERABLE MONOSTABLE MULTIVIBRATORS
SCLS420G – JUNE 1998 – REVISED APRIL 2003
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
recommended operating conditions (see Note 4)
SN54AHCT123A SN74AHCT123A
UNIT
MIN MAX MIN MAX
UNIT
V
CC
Supply voltage 4.5 5.5 4.5 5.5 V
V
IH
High-level input voltage 2 2 V
V
IL
Low-level input voltage 0.8 0.8 V
V
I
Input voltage 0 5.5 0 5.5 V
V
O
Output voltage 0 V
CC
0 V
CC
V
I
OH
High-level output current –8 –8 mA
I
OL
Low-level output current 8 8 mA
R
ext
External timing resistance 1k 1k Ω
∆t/∆V
CC
Power-up ramp rate 1 1 ms/V
T
A
Operating free-air temperature –55 125 –40 85 °C
NOTE 4: Unused R
ext
/C
ext
terminals should be left unconnected. All remaining unused inputs of the device must be held at V
CC
or GND to ensure
proper device operation. Refer to the TI application report, Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
V
CC
T
A
= 25°C SN54AHCT123A SN74AHCT123A
UNIT
PARAMETER
TEST
CONDITIONS
V
CC
MIN TYP MAX MIN MAX MIN MAX
UNIT
V
OH
I
OH
= –50 A
45V
4.4 4.5 4.4 4.4
V
V
OH
I
OH
= –8 mA
4
.
5
V
3.94 3.8 3.8
V
V
OL
I
OL
= 50 A
45V
0.1 0.1 0.1
V
V
OL
I
OL
= 8 mA
4
.
5
V
0.36 0.5 0.44
V
R
ext
/C
ext
†
V
I
= V
CC
or GND 5.5 V ±0.25 ±2.5 ±2.5
I
I
A, B,
and CLR
V
I
= V
CC
or GND 0 V to 5.5 V ±0.1 ±1* ±1
A
I
CC
Quiescent V
I
= V
CC
or GND, I
O
= 0 5.5 V 4 40 40 A
I
CC
Active state
(per circuit)
V
I
= V
CC
or GND,
R
ext
/C
ext
= 0.5 V
CC
5.5 V 560 750 975 975 A
∆I
CC
‡
One input at 3.4 V, Other
inputs at V
CC
or GND
5.5 V 1.35 1.5 1.5 mA
C
i
V
I
= V
CC
or GND 5 V 1.9 10 10 pF
* On products compliant to MIL-PRF-38535, this parameter is not production tested at V
CC
= 0 V.
†
This test is performed with the terminal in the off-state condition.
‡
This is the increase in supply current for each input at one of the specified TTL voltage levels rather than 0 V or V
CC
.
timing requirements over recommended operating free-air temperature range, V
CC
= 5 V ± 0.5 V
(unless otherwise noted) (see Figure 1)
TEST CONDITIONS
T
A
= 25°C SN54AHCT123A SN74AHCT123A
UNIT
TEST
CONDITIONS
MIN TYP MAX MIN MAX MIN MAX
UNIT
t
Pulse
CLR 5 5 5
ns
t
w
duration
A
or B trigger 5 5 5
ns
t
Pulse retrigger time
R
ext
= 1 kΩ, C
ext
= 100 pF
§
60
§ §
ns
t
rr
P
u
l
se re
t
r
i
gger
ti
me
R
ext
= 1 kΩ, C
ext
= 0.01 F
§
1.5
§ §
s
§
See retriggering data in the application information section.