Voltage control circuit for common mode voltage and method for controlling the same

Abstract

A common mode voltage detection circuit 105 detects a common mode voltage VCM from differential output terminals of a differential output circuit 101. The common mode voltage detection circuit outputs a detected voltage VCM2 in accordance with the common mode voltage VCM. An OTA 106 in the common mode feedback loop inputs or outputs multiple currents of the same phase in accordance with a voltage difference between a reference voltage VCM1 and the detected voltage VCM2. The respective multiple currents of the same phase are inputted/outputted to/from the two respective terminals of the differential output terminals. The common mode voltage can be reduced by flowing the currents into the differential output terminals, and can be increased by leading the currents from the differential output terminals. Thus, a phase margin or a gain margin of a control signal loop can be secured even with low current consumption, thereby realizing stable operation of the circuit.

Dependencies are inferred from the claim text.