公开(公告)号：WO1981001489A1

公开(公告)日：1981-05-28

申请号：PCT/US1980001365

申请日：1980-10-14

Applicant: MOTOROLA INC

Inventor： MOTOROLA INC ,  LEE R

IPC: H03K13/20

CPC classification number: H03M1/10 ,  H03M1/50

Abstract: A single slope analog to digital converter uses a DAC (21) to trim the discharge current of a capacitor (10) during calibration thereof. A method of calibrating the analog to digital converter is provided which iterates required steps to obtain a correct current setting within a short period of time. The analog to digital converter discharges a capacitor (10) through a high impedance to obtain a linear discharge. The time to discharge the capacitor (10) appears in a counter and is indicative of the voltage across the capacitor (10) at the beginning of the discharge period once the analog to digital converter has been calibrated.