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ADC_DOUT equation in LMP90080

Anbu Anbarasan
Prodigy 160 points
Other Parts Discussed in Thread: LMP90080

Hi,

                I am using LMP90080 to measure temperature using  RTD.In LMP90080 DS, there is a contradiction in equation for ADC_DOUT. In equation 15, ADC_DOUT = (VIN(Gain)/VREF)/2 power n and in equation 17, ADC_DOUT = (VIN(Gain)/2VREF)/2 power n.

Which one of those is correct equation?

I have used equation 15 for RTD in which I used the Topology #2 in figure 66.I connected two 3 wire RTD and I calculated the gain calculation for that.But if I remove one of the RTD, ADC reads double the voltage difference between the vref and voltage across RTD. Since ADC_DOUT is inversely proportional to VREF.

My question is, do I need to do gain calculation in program or is there a solution through hardware itself?Because I am a 

programmer and I donot have much knowledge in hardware.

Could somebody clarify the equation.?

Thanks and Regards

Anbu