PIC based A/V meter with V/F converter

[fjpompeo]

pic based voltage to current converter

Looking for a Voltage and Current meter using a PIC or AVR and a 1 x 16 LCD with Voltage to frequency converter to convert the real output voltage and current into frequencies that will be informed as Volt and Amp on the LCD. The ranges are 0-30V with 10mV steps and 0-5A with 1mA steps.

Regards and a happy new year to all

Fernando - call sign PU2PLL - Brazil

 

[Humber555]

Hi fjpompeo

Your project it´s very hardware dependable, considering you will need a 12 bit converter for voltage measurement and a 13 bit converter to reach the 1mA step in a 0 to 5A range. Take in mind that to handle suchs resolutions you will need the best ratio in temperature coefficient and tolerances in the discrete components you are going to use.
I will suggest the AD650JN from Analog Devices,
its a 14 bit resolution V/F Converter
Very Low Nonlinearity
0.002% typ at 10 kHz
0.005% typ at 100 kHz
0.07% typ at 1 MHz
Input Offset Trimmable to Zero

You will get full data at:


Analog Devices


Best regrds,

Humber555

 

[extradeath]

hi,
I know that it is a very late reply
but I'm still a new user
I'm working on a same similiar project but somehow big.
It is a harmonic analyser using a uC, I used pic16f877 but I have a problem is measuring the current from a working system without interrupt or a gret power loss. So, if you can help plz do so
THANK a lot

 

[IanP]

My suggestion is that you select A/D converter of 16bit resolution (after conversion you can ignore some LMBs) and select reference in such a way that each bit represents ,say , 1mV, 0.5mV etc. It just makes live easier.


Also, maybe I am missing something here, but:
Having HEX values after A/D conversion why are you going to convert this to frequecy and then display it on the LCD?