Original Publication Date: 1984-Oct-01
Included in the Prior Art Database: 2005-Feb-05
The figure shows a digital-to-analog (D/A) converter which is externally adjusted, for example, by changing the reference voltage or the closing time of a switch or both values. The converter consists of an operation amplifier, whose non-inverting input is grounded and whose inverting input is connected to switches S1 and S2 through a resistor R. S1 is connected to a reference voltage UREF, and S2 to the output of the operation amplifier. The usual capacitor C is arranged in the feedback path from the output to the inverting amplifier. Capacitor C is followed by a holding circuit for the last value. If the lowest-order bit is L, the initially uncharged capacitor C is charged to a voltage (Image Omitted) by closing switch Sl for the time tL .