Patent ID: 7663525
Filing Date: 2010-02-16
Classification: H03M

Abstract:
1. A digital to analog converter, comprising: a first capacitor storing a first voltage during a first period; a second capacitor storing a second voltage during the first period; an operational amplifier comprising a non-inverting input, an inverting input, a non-inverting output, and an inverting output; a third capacitor connected between the inverting input and the non-inverting output; a fourth capacitor connected between the non-inverting input and the inverting output; and a plurality of switches for coupling the first and the second capacitors with the operational amplifier in parallel according to a digital signal during a second period, wherein when the first capacitor is connected to the third capacitor in parallel, the second capacitor is connected to the fourth capacitor in parallel, and wherein when the first capacitor is connected to the fourth capacitor in parallel, the second capacitor is connected to the third capacitor in parallel.