Protect PIC's input against "high" voltage using AD

[chuck]

flotulopex they are some batteries there,
I did a battery anayliser to test 6V batteries based on the alphabat pro, It works really well, The only real way to test batteries is the discharge method, It uses a pic18f4520,GLCD & SD_CARD for recording the date,time,battery and current draw, This unit works very well.

If you want accuracy then have a look at the attached file, It's part of a schematic from a fluke meter and it ues a 10bit A/D converter, You could can control the auto ranging through the PIc and if need be you could always use a 12-24Bit A/D chip. If I rmember the max DC voltage is 600V, This is one of my next projects.

have you thought about hard wiring the unit to the batteries and using RF or RS232 way, You could have one or two master units then salves units to send data and why not go all the way, Use a SD_Card so log the voltage and you can upload the data into EXcel These are just some ideas but it would amake it cool project