how to interface the sensor's ouput with adc of microcontroller

[alphonsjp]

Dear all..
I've my sensor output ranges from ( 15mV to 45 mV). I've to interface the sensor's output to the adc of a microcontroller. Can i connect directly the sensor's output to the microcontroller? Or should i use any signal conditioning circuit.?
2. My second question is i've another sensor whose output ranges from 2 V to 4 V. So i'm in a confused state about the interfacing of these sensor to the input of adc.
Please help..

 

[crutschow]

For best dynamic range and resolution you normally adding a signal conditioning circuit to amplify and offset the signal so that it matches the voltage range of the ADC input. Thus if the input range is 0V to 5V then you would amplify/offset the signal, typically with op amps or an instrumentation amp, to give 0V for the sensor's minimum signal and 5V for the sensor's maximum signal.

 

[alphonsjp]

Sir
Only for the first sensor i need to use the signal conditioning circuit?