Making Digital Multimeter

[nicko-391]

Want helps

I want to build multimeter which can measure V,I,R,C etc.I hope to use PIC,ADC...But i have nt clear idea about how Current is measured ,how maintain autoranges..please give me some ideas,directions to do this project.

 

[rajudp]

current can be measured with a shunt resister, and for autorange you can use analog switches starting from high level to low level

 

[nicko-391]

can u explain how to implement the R ladder for auto range?

 

[hugo]

Re: Want helps to make Digital Multimeter

I want to build multimeter which can measure V,I,R,C etc.I hope to use PIC,ADC...But i have nt clear idea about how Current is measured ,how maintain autoranges..please give me some ideas,directions to do this project.

It's called Superprobe and it's not a digital multimeter (logic pulser, frequency counter, voltmeter, capacitance meter, signal generator and serial ASCII data output) but it's going to give you some idea ... check it out :

http://www.benryves.com/journal/3632205

and the C source code :

http://www.benryves.com/bin/superprobe/superprobe.zip

 

[cocoloco]

Re: Want helps to make Digital Multimeter

Check this Chip and datasheet,it can make you an inspiration about your project

NJU9210CF

datasheet


i have in stock but i never played with,a lot's of Multimeter on the market have this chip inside.

 

[nicko-391]

Re: Want helps to make Digital Multimeter

I cheked it out.It suit for my project.How can I buy this IC? It is not in e-bay.I coudnt found any distributor.

 

[hugo]

Another good one here "Mega Meter" :


http://members.shaw.ca/Botgoodies2/MegaMeter/MegaMeter.htm

 

[cocoloco]

How can I buy this IC? It is not in e-bay.I coudnt found any distributor.

check at Products list[Semiconductor Selection Guides[New Japan Radio]]

and if i remember,you can ask for Sample.
and have a world distributor:grin: