Patent ID: 8547075

Claim:
An integrated circuit comprising: a first voltage regulator including: an operational amplifier (op amp) having an input and a first output, the input connected to an internal node; an output stage having an input and a second output, the input connected to the first output of the op amp and the second output connected to the internal node; and a current sink connected to the internal node; a second voltage regulator including: an operational amplifier (op amp) having an input and a first output, the input connected to an internal node; an output stage having an input and a second output, the input connected to the first output of the op amp and the second output connected to the internal node; and a current sink connected to the internal node; first and second switches, each switch having a first terminal for directly connecting the switch to a common voltage reference and a second terminal; and a first capacitor having first and second plates, the first plate connected to the second terminal of the first switch and the internal node of the second voltage regulator and the second plate connected to the second terminal of the second switch and the internal node of the first voltage regulator, wherein: to operate the first voltage regulator, the first switch is closed and the second switch is open, such that the first plate of the first capacitor is directly connected to the common voltage reference and the second plate of the first capacitor is connected to the internal node of the first voltage regulator; and to operate the second voltage regulator, the first switch is open and the second switch is closed, such that the first plate of the first capacitor is connected the internal node of the second voltage regulator and the second plate of the first capacitor is directly connected to the common voltage reference.