An operational transconductance amplifier includes a fully-differential amplifying circuit, a bias driving circuit, and a common mode feedback circuit. The fully-differential amplifying circuit is configured for receiving a differential input voltage and providing a differential output voltage. The fully-differential amplifying circuit includes a plurality of diffusor-differential-pair circuits. The bias driving circuit is configured for providing at least one first bias current to drive the fully-differential amplifying circuit and adjust the transconductance of the transconductance amplifier. The common mode feedback circuit is configured for stabilizing the differential output voltage. An operational transconductance amplifier-capacitor (OTA-C) filter and a high order filter are disclosed herein as well.
展开▼
