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Single supply operation of AD628 and AD8436

Question asked by Arhez on Oct 9, 2015
Latest reply on Oct 13, 2015 by Arhez

Hi,

I posted a question earlier where I asked people here about isolation methods I can apply for measuring AC voltage of 220V/60 Hz using AD8436, here is the link if you are interested

 

Measuring DC Voltage with AD8436

I could not really get a solution. So I looked more when I had time and came across this article,

 

Simple circuit measures RMS value of AC power line | EE Times

 

In this article the authors have implemented a solution for measuring RMS value of AC power line. These guys have solved the isolation problem but the issue here is the dual supply in both AD628 and AD8436. I can only use a single supply. There is definitely the option of single supply usage in both the Ics but in the datasheet of AD628 it is clearly mentioned that for single supply voltage of 15V the maximum input I can apply to the chip's input is of 80V if I am not wrong. How can I use it for 220VAC? The article talks about using a resistor over the input to use it for bigger ranges but that is the scenario for dual supply ranges I am guessing. So my questions

 

1. Will I be able to get 220VAC scaled down to mV by using a single supply voltage of 12V? How should I redesign this circuit if I can?

2. And what about AD8436? Will a single supply voltage of 12V be enough for it to convert the output from AD628 to 5VDC?

 

Regards

 

Arhez

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