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dual tracking powersupply interface with pic & display in LCD

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Newbie level 5
Apr 13, 2011
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hi, i want to make a variable regulated power supply. i need a circuit for variable dual tracking power supply using pic microcontroller, and display the voltage in LCD display. i used LM317&337, kindly explain me with ckt, how to interface the -ve voltage (ie o/p from LM337) part to the microcontroller. potentiometer on LM317 is connected to the +ve part.

Do you want the micro to only display the output voltages ?
Exactly how do you want to control the output voltages ? ( by pot or by micro and how?)

yes.. i want to read the output as +12v & -12V in the lcd display. the output is made by adjusting the pot. micro is used only to display thru lcd..(I cant send u the schematic.. i ll try to do). i used LM317 for +ve voltage, it is controlled by pot to vary to +12V. and the connectd to micri... then i used LM337 for -ve voltage. i want to connect this output to the microcontroller to read -12v.

can anybody provide me a sample mc coding for this project.
the voltage and the current tat i give as input thru the pot and the output regulated, should b displayed in the lcd. i use 20x4 hd44780 and pic16f767 mc.

J1 is the transformer to get the o/p of 24V thru LM7824,
J2 to get the o/p of +5v to the mc using lm7805,
J3- to get variable 1.5-5V thru lm317,
J4- to get + & -12V thru lm317 & lm337 resp.,
J5- to get + & - 15V for the voltage of lm358.
lm358 is used as inv. opamp, tat helps the mc to read and display -ve voltage (-12V).
The mc is connected to LCD to display the o/p.
pls provide a sample code...


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