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Details, datasheet, quote on part number:SN54AHCT123A
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Datasheet text preview:
SN54AHCT123A, SN74AHCT123A DUAL RETRIGGERABLE MONOSTABLE MULTIVIBRATORS
SCLS420G JUNE 1998 REVISED APRIL 2003
D D D D D D D
Inputs Are TTL-Voltage Compatible Schmitt-Trigger Circuitry On A, B, and CLR Inputs for Slow Input Transition Rates Edge Triggered From Active-High or Active-Low Gated Logic Inputs Retriggerable for Very Long Output Pulses Overriding Clear Terminates Output Pulse Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II ESD Protection Exceeds JESD 22 2000-V Human-Body Model (A114-A) 200-V Machine Model (A115-A) 1000-V Charged-Device Model (C101)
SN54AHCT123A . . . J OR W PACKAGE SN74AHCT123A . . . D, DB, DGV, N, OR PW PACKAGE (TOP VIEW)
1A 1B 1CLR 1Q 2Q 2Cext 2Rext/Cext GND
1 2 3 4 5 6 7 8
16 15 14 13 12 11 10 9
VCC 1Rext/Cext 1Cext 1Q 2Q 2CLR 2B 2A
SN54AHCT123A . . . FK PACKAGE (TOP VIEW)
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
TA PDIP N SOIC D 40°C to 85°C to 85°C SSOP DB TSSOP PW TVSOP DGV CDIP J 55°C to 125°C CFP W LCCC FK PACKAGE Tube Tube Tape and reel Tape and reel Tape and reel Tape and reel Tube Tube Tube
1B 1A NC VCC 1R ext /C ext 1CLR 1Q NC 2Q 2Cext
4 5 6 7 8 3 2 1 20 19 18 17 16 15 14 9 10 11 12 13
description/ordering information
1Cext 1Q NC 2Q 2CLR
NC No internal connection
ORDERABLE PART NUMBER SN74AHCT123AN SN74AHCT123AD SN74AHCT123ADR SN74AHCT123ADBR SN74AHCT123APWR SN74AHCT123ADGVR SNJ54AHCT123AJ SNJ54AHCT123AW 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.
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.
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
2R ext /Cext GND NC 2A 2B
TOP-SIDE MARKING SN74AHCT123AN AHCT123A HB123A HB123A HB123A SNJ54AHCT123AJ SNJ54AHCT123AW SNJ54AHCT123AFK
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SN54AHCT123A, SN74AHCT123A DUAL RETRIGGERABLE MONOSTABLE MULTIVIBRATORS
SCLS420G JUNE 1998 REVISED APRIL 2003
description/ordering information(continued)
Pulse triggering occurs at a particular voltage level and is not directly related to the transition time of the input pulse. The A, B, and CLR inputs have Schmitt triggers with sufficient hysteresis to handle slow input transition rates with jitter-free triggering at the outputs. Once triggered, the basic pulse duration can be extended by retriggering the gated low-level-active (A) or high-level-active (B) input. Pulse duration can be reduced by taking CLR low. CLR input can be used to override A or B inputs. The input/output timing diagram illustrates pulse control by retriggering the inputs and early clearing. The variance in output pulse duration from device to device typically is less than ±0.5% for given external timing components. An example of this distribution for the 'AHCT123A is shown in Figure 10. Variations in output pulse duration versus supply voltage and temperature are shown in Figure 6. During power up, Q outputs are in the low state, and Q outputs are in the high state. The outputs are glitch free, without applying a reset pulse. For additional application information on multivibrators, see the application report, Designing With the SN74AHC123A and SN74AHCT123A, literature number SCLA014.
FUNCTION TABLE (each multivibrator) INPUTS CLR L X X H H A X H X L B X X L H H OUTPUTS Q L L L Q H H H
#
L
These outputs are based on the assumption that the indicated steady-state conditions at the A and B inputs have been set up long enough to complete any pulse started before the setup.
logic diagram, each multivibrator (positive logic)
Rext/Cext A B CLR Cext Q R Q
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POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
SN54AHCT123A, SN74AHCT123A DUAL RETRIGGERABLE MONOSTABLE MULTIVIBRATORS
SCLS420G JUNE 1998 REVISED APRIL 2003
input/output timing diagram
tr r A
B
CLR
Rext/Cext
Q
Q tw tw tw + t r r
absolute maximum ratings over operating free-air temperature (unless otherwise noted)
Supply voltage range, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 V to 7 V Input voltage range, VI (see Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 V to 7 V Output voltage range, VO (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 V to VCC + 0.5 V Input clamp current, IIK (VI VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA Continuous output current, IO (VO = 0 to VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±25 mA Continuous current through VCC or GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±50 mA Package thermal impedance, JA (see Note 3): D package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73°C/W DB package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82°C/W DGV package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120°C/W N package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67°C/W PW package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108°C/W Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65°C to 150°C
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. Voltage values are with respect to the network ground terminal. 2. The input and output voltage ratings may be exceeded if the input and output current ratings are observed. 3. The package thermal impedance is calculated in accordance with JESD 51-7.
POST OFFICE BOX 655303
· DALLAS, TEXAS 75265
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