Patent ID: 7852152
Filing Date: 2010-12-14
Classification: H03F,H03H

Abstract:
1. A circuit comprising: a first operational transconductance amplifier comprises differential inputs and differential outputs; a second operational transconductance amplifier comprises (i) differential inputs including a first differential input and a second differential input, and (ii) a first differential output and a second differential output, a first output of the first operational transconductance amplifier being coupled to the first differential input being an inverting input and a second output of the first operational transconductance amplifier being coupled to the second differential input being a non-inverting input, the first differential output being coupled to a first input of the first operational transconductance amplifier, and the second differential output being coupled to a second input of the first operational transconductance amplifier for negative feedback and current biasing; and a first biasing control circuit being coupled to the differential inputs of the first operational transconductance amplifier, the first biasing control circuit provides proper biasing voltage for the first operational transconductance amplifier by maintaining an average input voltage of the first operational transconductance amplifier equal to a reference voltage.