Resolution problem for A2D process

Edmond

I am working on a force sensor with the Basic Stamp.
I am using the MAXIM 1270 A2D converter to read the sensor output using the Basic Stamp.
The range of the analog input for the A2D converter is 0~5 v. Bu tthe output range of the force sensor is in mV unit which is very small.
Since this is a 12bit converter, the resolution for each step is .0012v which is too high to read this sensor output.
The reading doesn't change at all even the force is changing more than a pound.

So what can I do to make my A2D converter able to read the sensor output in a better resolution?
Should I build a circuit to scale my sensor output from mV to V?
Any other solutions I can try?

Mike Green

Essentially, you add an amplifier to convert the mV readings from your sensor to a 0-5V range for the ADC. Do a web search for "instrumentation amplifier" or try the Wikipedia with a search for "wiki instrumentation amplifier". These are amplifiers specifically designed for this sort of use.

MSDTech

You might take a look at the Analog Devices AD77xx family of ADC's. They have an amplifier built into the ADC which easily works in the mV range.