SN54AHCT123A Datasheet, PDF (1/21 Pages) Texas Instruments – DUAL RETRIGGERABLE MONOSTABLE MULTIVIBRATORS

SN54AHCT123A, SN74AHCT123A
DUAL RETRIGGERABLE MONOSTABLE MULTIVIBRATORS
D Inputs Are TTL-Voltage Compatible
D Schmitt-Trigger Circuitry On A, B, and CLR
Inputs for Slow Input Transition Rates
D Edge Triggered From Active-High or
Active-Low Gated Logic Inputs
D Retriggerable for Very Long Output Pulses
D Overriding Clear Terminates Output Pulse
D Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
D ESD Protection Exceeds JESD 22
– 2000-V Human-Body Model (A114-A)
– 200-V Machine Model (A115-A)
– 1000-V Charged-Device Model (C101)
description/ordering information
These edge-triggered multivibrators feature
output pulse-duration control by three methods. In
the first method, the A input is low, and the B input
goes high. In the second method, the B input is
high, and the A input goes low. In the third method,
the A input is low, the B input is high, and the clear
(CLR) input goes high.
The output pulse duration is programmed by
selecting external resistance and capacitance
values. The external timing capacitor must be
connected between C_ext and R_ext/C_ext (positive)
and an external resistor connected between
R_ext/C_ext and V_CC. To obtain variable pulse
durations, connect an external variable resistance
between R_ext/C_ext and V_CC. The output pulse
duration also can be reduced by taking CLR low.
SCLS420G – JUNE 1998 – REVISED APRIL 2003
SN54AHCT123A . . . J OR W PACKAGE
SN74AHCT123A . . . D, DB, DGV, N, OR PW PACKAGE
(TOP VIEW)
1A ₁
1B 2
1CLR 3
1Q 4
2Q 5
2C_ext 6
2R_ext/C_ext 7
GND 8
16 ^V_CC
15 1R_ext/C_ext
14 1C_ext
13 1Q
12 2Q
11 2CLR
10 2B
9 2A
SN54AHCT123A . . . FK PACKAGE
(TOP VIEW)
1CLR
1Q
NC
2Q
2C_ext
3 2 1 20 19
4
18
5
17
6
16
7
15
8
14
9 10 11 12 13
1C_ext
1Q
NC
2Q
2CLR
NC – No internal connection
ORDERING INFORMATION
TA
PACKAGE†
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
PDIP – N
Tube
SN74AHCT123AN
SN74AHCT123AN
–40°C to 85°C
SOIC – D
SSOP – DB
Tube
Tape and reel
Tape and reel
SN74AHCT123AD
SN74AHCT123ADR
SN74AHCT123ADBR
AHCT123A
HB123A
TSSOP – PW Tape and reel SN74AHCT123APWR HB123A
TVSOP – DGV Tape and reel SN74AHCT123ADGVR HB123A
CDIP – J
Tube
SNJ54AHCT123AJ
SNJ54AHCT123AJ
–55°C to 125°C CFP – W
Tube
SNJ54AHCT123AW
SNJ54AHCT123AW
LCCC – FK
Tube
SNJ54AHCT123AFK
SNJ54AHCT123AFK
† _{Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are}
available at www.ti.com/sc/package.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
Copyright  2003, Texas Instruments Incorporated
On products compliant to MIL-PRF-38535, all parameters are tested
unless otherwise noted. On all other products, production
processing does not necessarily include testing of all parameters.
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