Operational transconductance amplifier with independent transconductance and common mode feedback control

An integrated biquadratic, continuous-time filter section comprising:

• a plurality of operational transconductance amplifiers (OTAs);
• each OTA including four differential transistor pairs;
• adjustable voltage means for simultaneously changing a transconductance (GM) of each of the OTAs by adjusting a differential voltage applied to each of said four differential transistor pairs;
• and
• each of said OTAs including a plurality of current sources and common mode feedback means for controlling a common mode output voltage level.

An integrated operational transconductance amplifier (OTA) comprising:

• four differential transistor pairs;
• means for changing a transconductance (GM) of the OTA by adjusting a differential voltage applied to each of said four differential transistor pairs;
• a plurality of current sources;
• common mode feedback means for controlling a common mode output voltage level;
• and
• said means for changing a transconductance (GM) of the OTA being independent of said common mode output voltage level control.