Is it possible to measure voltage inside a circuit with MCU?

[ericmar]

Hi,

Is it possible to measure voltage inside a circuit with MCU embedded in the circuit? I saw it somewhere whereby the device is running an utility test on itself and it's able to display some voltages within its circuit by itself. I wonder how it works?

Does anyone here know abt this?

Thanks,
Eric

 

[instruite]

Re: Is it possible to measure voltage inside a circuit with

Yes it is possible.
and it is normally used in commercial circuits for measuring battery voltage (VB), regulator output voltages (Vcc) depending on the requirements

Its just same as measuring an external voltage
Only difference is that the voltage source is internal in the circuit

For example lets say you are running a circuit @ battery voltage = 12V
and you want to measure battery voltage
So you just use voltage divider and a low pass filter and coonect the signal to the ADC of the microcontroller
then you can know what is the voltage you are getting from your battery

 

[DrWhoF]

Re: Is it possible to measure voltage inside a circuit with

Connect AD pins of MCUs to points you want to measure and measure them in the same way as you measure anything else.
DrWho

 

[ericmar]

Re: Is it possible to measure voltage inside a circuit with

Yes it is possible.
and it is normally used in commercial circuits for measuring battery voltage (VB), regulator output voltages (Vcc) depending on the requirements

Its just same as measuring an external voltage
Only difference is that the voltage source is internal in the circuit

For example lets say you are running a circuit @ battery voltage = 12V
and you want to measure battery voltage
So you just use voltage divider and a low pass filter and coonect the signal to the ADC of the microcontroller
then you can know what is the voltage you are getting from your battery

Very interesting!
I want to know more abt the actual operation. I think I should do some research on this area and try it out in some of my designs.

 

[leomecma]

Re: Is it possible to measure voltage inside a circuit with

Some people use it for save atual context and important parameters, before power supply of system go down (When it below 95% of nominal operation for example), but in this case you need capacitors with large value and low ESR. Others use to switch between power supply and lithium battery backup systems.

leomecma

 

[ericmar]

Re: Is it possible to measure voltage inside a circuit with

Connect AD pins of MCUs to points you want to measure and measure them in the same way as you measure anything else.
DrWho

Wat abt the programming part? How do I check the voltage level?

 

[chicken_feet]

Re: Is it possible to measure voltage inside a circuit with

Hi,

That portion is called ADC-Analog Digital Conversion. Perhaps you can read up on that.

rgds,
chicken_feet

 

[janakiram.sistla]

Re: Is it possible to measure voltage inside a circuit with

hi
When it comes to measure outside voltage using controller first check if it is ac or dc voltage .If it is ac use current transformer to downcovert it by a factor and then using adc .pic supports a lot of applications of this sought which u can download from www.microchip.com

 

[samcheetah]

Re: Is it possible to measure voltage inside a circuit with

go to http://www.winpicprog.co.uk

the PIC tutorials on the above site has a tutorial for ADCs

 

[sathishdn]

How decide the wattage of the resistor

 

[vijay s]

Re: Is it possible to measure voltage inside a circuit with

@instruite
Measuring Internal Voltage seems to be Very interesting.. Can you post any Circuit diagram for this and program Idea.