Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.NET

X  

TL7709A Datasheet(PDF) 6 Page - Texas Instruments

Click here to check the latest version.
Part # TL7709A
Description  Supply voltage Supervisor
Download  17 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  TI [Texas Instruments]
Direct Link  http://www.ti.com
Logo TI - Texas Instruments

TL7709A Datasheet(HTML) 6 Page - Texas Instruments

Back Button TL7709A Datasheet HTML 2Page - Texas Instruments TL7709A Datasheet HTML 3Page - Texas Instruments TL7709A Datasheet HTML 4Page - Texas Instruments TL7709A Datasheet HTML 5Page - Texas Instruments TL7709A Datasheet HTML 6Page - Texas Instruments TL7709A Datasheet HTML 7Page - Texas Instruments TL7709A Datasheet HTML 8Page - Texas Instruments TL7709A Datasheet HTML 9Page - Texas Instruments TL7709A Datasheet HTML 10Page - Texas Instruments Next Button
Zoom Inzoom in Zoom Outzoom out
 6 / 17 page
background image
Circuit Description
2
Literature Number: SLVAE04
In larger computers several features are provided to prevent such errors: a power-fail interrupt signals
dangerous conditions in time, the content of the memory is protected by a battery back-up, and so on. In
small microcomputer systems this amount of effort is too expensive, and in most applications also not
required. It is usually sufficient if, after a serious voltage drop, the microcomputer is forced into a defined
initial condition. To implement this function, whilst preventing the problems mentioned above, the following
circuit features are required:
− Accurate detection of a serious voltage drop.
− Generation of a reset signal while as the supply voltage is not in the operational
range, to prevent undefined operations of the microcomputer.
− Maintenance of the reset signal for a certain time after the supply voltage has
returned to its nominal value, to ensure proper initialization of the circuit.
For these applications, Texas Instruments has developed a series of integrated circuits which, with a
minimum of external components and without additional adjustment, will fulfill the requirements described
above.
2. Circuit Description
The main part of this circuit is a reference voltage source, which consists of a very stable, temperature-
compensated band gap reference. An external capacitor (typ. 0.1
µF) must be connected to the voltage
output V
ref, to reduce the influence of fast transients in the supply voltage. The voltage at the SENSE input
is divided by a resistor divider and compared with the reference voltage by a comparator. To achieve high
accuracy, this divider is adjusted at wafer probe. When the input voltage is sensed to be lower than the
threshold voltage, the thyristor is triggered, which discharges the timing capacitor C
t. It is also possible to
fire the thyristor via the RESIN input by a logic level (TTL level, active low). The thyristor is turned off again
when either the voltage at the SENSE input (or RESIN input) increases beyond the threshold, or - during
short supply voltage drops - the discharge current of the capacitor becomes lower than the hold current of
the thyristor.
Thereafter, the capacitor is recharged by a current source 100
µA, the charge time being calculated as
follows:
t
C
d
t
=
1 3 10
4
.
Ct in F, t in s
The magnitude of charge current and therefore also the delay t
d time is determined by the tolerance of the
resistors in the integrated circuit. These tolerances, caused by the semiconductor manufacturing process,
are not negligible. Therefore the delay time may vary -50% to +100 %. However, for the applications
discussed here this will not be a restriction. The diagram in figure 3 shows the typical delay time t
d versus
the capacitance of the external capacitor C
t.


Similar Part No. - TL7709A

ManufacturerPart #DatasheetDescription
logo
STMicroelectronics
TL7709A STMICROELECTRONICS-TL7709A Datasheet
67Kb / 7P
   SUPPLY VOLTAGE SUPERVISORS
logo
Texas Instruments
TL7709A TI-TL7709A Datasheet
140Kb / 10P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISORS
TL7709A TI-TL7709A Datasheet
346Kb / 17P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISORS
TL7709A TI-TL7709A Datasheet
552Kb / 21P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISORS
TL7709ACD TI-TL7709ACD Datasheet
140Kb / 10P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISORS
More results

Similar Description - TL7709A

ManufacturerPart #DatasheetDescription
logo
Texas Instruments
TL7700 TI1-TL7700_16 Datasheet
1Mb / 23P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISOR
logo
Toshiba Semiconductor
TA8505P TOSHIBA-TA8505P Datasheet
213Kb / 6P
   SUPPLY VOLTAGE SUPERVISOR
logo
Texas Instruments
TL7700 TI-TL7700_06 Datasheet
266Kb / 15P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISOR
TL7700 TI-TL7700 Datasheet
144Kb / 11P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISOR
1633903 TI-1633903 Datasheet
774Kb / 22P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISOR
TL7700 TI-TL7700_07 Datasheet
400Kb / 17P
[Old version datasheet]   SUPPLY-VOLTAGE SUPERVISOR
logo
California Micro Device...
CM3403 CALMIRCO-CM3403 Datasheet
183Kb / 6P
   Micropower Supply Voltage Supervisor (SVS)
CM3404 CALMIRCO-CM3404 Datasheet
295Kb / 6P
   Micropower Supply Voltage Supervisor (SVS)
logo
Texas Instruments
TPS3831 TI-TPS3831 Datasheet
906Kb / 24P
[Old version datasheet]   Ultralow Power, Supply Voltage Supervisor
TLV809 TI1-TLV809 Datasheet
929Kb / 20P
[Old version datasheet]   3-Pin Supply Voltage Supervisor
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.NET
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com