ADC0809 to PIC16FXX & LCD interface......

Need some help! :?

I want to build a digital power supply using ADC0809 and PIC16f84 with an 4x20 LCD readout and 12button keypad. I need some idea for the voltage regulation regulation and how can i connect my ADC, PIC, keypad and LCD. My desired output is from 3V to 25V with an incremental value of 0.1V with a max current of 3A. Circuits diagrams are highly appreciated. or if there are any suggestions, ideas and comments are also welcome.

Please Help!! :wink: :lol:

engr.ronche said:

Need some help! :?

I want to build a digital power supply using ADC0809 and PIC16f84 with an 4x20 LCD readout and 12button keypad. I need some idea for the voltage regulation regulation and how can i connect my ADC, PIC, keypad and LCD. My desired output is from 3V to 25V with an incremental value of 0.1V with a max current of 3A. Circuits diagrams are highly appreciated. or if there are any suggestions, ideas and comments are also welcome.

Please Help!! :wink: :lol:

Click to expand...

Personally I would use a higher spec PIC, the 16F84 is rather lacking in I/O pins (you would have to use pins to do more than one function, making life greatly more complicated) - moving to the 16F876 (28 pin) would give you sufficient pins, plus an internal 10 bit ADC - so you wouldn't need the external ADC.

The main 'problem' is getting an analogue output from the PIC, with the 16F876 you could use the hardware PWM and filter the output to give an analogue reference voltage. Failing that you could use an external DAC, a digital potentiometer, even a simple R2R ladder network.

iyhh

QUOTE=engr.ronche]Need some help! :?

I want to build a digital power supply using ADC0809 and PIC16f84 with an 4x20 LCD readout and 12button keypad. I need some idea for the voltage regulation regulation and how can i connect my ADC, PIC, keypad and LCD. My desired output is from 3V to 25V with an incremental value of 0.1V with a max current of 3A. Circuits diagrams are highly appreciated. or if there are any suggestions, ideas and comments are also welcome.

Please Help!! :wink: :lol:[/QUOTE]

if you now the solution of this probem please send it to me very quicly

Dump the antique 16F84 and ADC0809 and use a modern PIC with built-in A2D, everything you need is in my tutorials!.