Patent ID: 7504972

Claim:
A method for increasing a resolution of an analog to digital conversion, using a microcontroller having an analog to digital converter and a configurable input/output port, a sense voltage to be converted is presented to the input/output port though a resistive-capacitive network, the resolution is increased to a desired resolution step size Δ c equal to a fraction 1/N of a native resolution step size of the analog to digital converter, the method comprising steps of: a) measuring the sense voltage with the configurable input/output port configured for input and assigning the measured sense voltage value to M 1 ; b) repeating for K=1 to N−1 steps c) to g): c) modifying the sense voltage by driving the configurable input/output port to a high voltage, with the configurable input/output port configured for output, for a period of time determined to modify the sense voltage by an amount equal to K times the desired resolution step size Δ c ; d) measuring the modified sense voltage with the configurable input/output port configured for input and assigning the measured sense voltage value to M K+1 ; e) comparing M K+1 with M K ; f) continuing to repeat the steps c) to g) when M K+1 =M K ; and g) ending the repeating of the steps c) to g) when M K+1 is not equal to M K ; wherein a resulting value of the conversion is equal to M 1 when all measurements M 1 to M N are equal; and the resulting value of the conversion is equal to M 1 +(N−K) Δ c when M K+1 is not equal to M K .