SN54AHCT123A, SN74AHCT123A
DUAL RETRIGGERABLE MONOSTABLE MULTIVIBRATORS
SCLS420G – JUNE 1998 – REVISED APRIL 2003
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
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 Cext and Rext/Cext (positive)
and an external resistor connected between
Rext/Cext and VCC. To obtain variable pulse
durations, connect an external variable resistance
between Rext/Cext and VCC. The output pulse
duration also can be reduced by taking CLR low.
ORDERING INFORMATION
TAPACKAGE†ORDERABLE
PART NUMBER TOP-SIDE
MARKING
PDIP – N Tube SN74AHCT123AN SN74AHCT123AN
Tube SN74AHCT123AD
–
Tape and reel SN74AHCT123ADR
–
SSOP – DB Tape and reel SN74AHCT123ADBR HB123A
TSSOP – PW Tape and reel SN74AHCT123APWR HB123A
TVSOP – DGV Tape and reel SN74AHCT123ADGVR HB123A
CDIP – J Tube SNJ54AHCT123AJ SNJ54AHCT123AJ
–55°C to 125°CCFP – 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.
Copyright 2003, Texas Instruments Incorporated
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.
SN54AHCT123A ...J OR W PACKAGE
SN74AHCT123A . . . D, DB, DGV, N, OR PW PACKAGE
(TOP VIEW)
SN54AHCT123A . . . FK PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
1A
1B
1CLR
1Q
2Q
2Cext
2Rext/Cext
GND
VCC
1Rext/Cext
1Cext
1Q
2Q
2CLR
2B
2A
3212019
910111213
4
5
6
7
8
18
17
16
15
14
1Cext
1Q
NC
2Q
2CLR
1CLR
1Q
NC
2Q
2Cext
1B
1A
NC
2A
2B V
1R
2R GND
NC CC
NC – No internal connection
ext/Cext
ext/Cext
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.
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.