초록 ▼

A low-power dual-g.sub.m differential operational transconductance amplifier (OTA) having a differential input for improved common-mode noise rejection, a high transconductance for power savings, and circuitry for controlling its output conductance. The OTA includes a pair of input inverters for rec

A low-power dual-g.sub.m differential operational transconductance amplifier (OTA) having a differential input for improved common-mode noise rejection, a high transconductance for power savings, and circuitry for controlling its output conductance. The OTA includes a pair of input inverters for receiving differential input signals, a common-mode voltage control circuit for controlling the DC voltage levels of the inverters, and a Q-control circuit for adjusting the OTA's output conductance. The common-mode voltage control circuit has a pair of compensating current sources and a feedback loop acting as a high-gain amplifier. The high-gain amplifier has a pair of comparators for respectively comparing the DC voltage levels of the inverter outputs with a reference voltage. The Q-control circuit includes a current source coupled to a crossed-coupled NMOS transistor pair such that the OTA's output conductance may be controlled by adjusting the current source.

대표청구항 ▼

[ What is claimed is:] [1.] A differential operational transconductance amplifier (OTA) for amplifying a differential input having positive and negative input signals, the OTA having positive and negative outputs and an output conductance, comprising:a pair of inverters for respectively receiving th

[ What is claimed is:] [1.] A differential operational transconductance amplifier (OTA) for amplifying a differential input having positive and negative input signals, the OTA having positive and negative outputs and an output conductance, comprising:a pair of inverters for respectively receiving the positive and negative input signals, the output of each inverter having a DC voltage level and coupled to a respective OTA output;a common-mode voltage control circuit coupled to the output of each inverter for controlling the DC voltage level of the inverter; anda Q-control circuit coupled to the outputs of the inverters for adjusting the output conductance of the OTA.