How to properly connect PT 100 sensor to ADC0804

[naveshece]

PT 100 To ADC

Hi all,

I have connected my PT 100 sensor to the bridge circuit which i added here gives the variations in Milli volts. I have used the ADC 0804 with AT 89S52 microcontroller.

I have the problem of the ADC did'nt give the value to the controller..

Is that the reason of the PT 100 output voltage is in mv?

Also the output of the bridge is two terminals. One terminal i have connected to +vin another terminal in which pin I have connect?

Is there any amplifier needed?

Kindly give me the solution..

Thank you.

 

[mayankmevada]

Re: PT 100 To ADC

yes,
you need amplifier to convert differential voltage to single ended signal. You can use instrumentation amplifier or simple differential amplifier.

 

[y.gh]

PT 100 To ADC

hi
u must use amplifier befoar connecting yourbridg to micro.u can use external amplifier(such as op-amp)or internal pri amplifier in microcontroller.u can use datasheet of your ic for useing internal amplifier.