The TC815 is a 3-1/2 digit integrating analog-to-digital converter with triplex LCD display drive and automatic ranging. A display hold function is on-chip. Input voltage/ohm attenuators ranging from 1 to 1/10,000 are automatically selected. Five full scale ranges are provided. The CMOS TC815 contains all the logic and analog switches needed to manufacture an autoranging instrument for ohms and voltage measurements. User selected 20mA and 200mA current ranges are available. Full scale range and decimal point LCD annunciators are automatically set in auto-range operation. Auto-range operation is available during ohms (high and low power ohms) and voltage (AC and DC) measurements, eliminating expensive range switches in hand-held DMM designs. The auto-range feature may be bypassed allowing decimal point selection and input attenuator selection control through a single line input. Expensive rotary switches are not required.