| 摘要 |
A transconductor block including a Czarnul tuning network, transconductance resistors, an input voltage follower amplifier, a common mode circuit, PMOS transistors coupled in cascode configuration, an input current source, and high gain amplifiers that drive NMOS transistors at the output. The input voltage follower amplifier receives a differential input signal including a common mode voltage and applies the differential input signal to the Czarnul tuning network. The Czarnul tuning network includes series resistors and is coupled in parallel with the transconductance resistors. The common mode circuit receives the differential input signal and a reference common mode voltage and provides a bias voltage and a common mode feedback voltage. The common mode circuit asserts the common mode feedback voltage to the output PMOS transistors to establish a DC output current and to minimize drift of the common mode voltage of the transconductance block. Also, the bias voltage is level shifted from the common mode signal. The high gain amplifiers maintain the output of the Czarnul tuning network and transconductance resistors at the bias voltage. The high gain amplifiers are coupled to the input current sources and to the NMOS transistors in a negative feedback configuration. The high gain amplifiers drive the NMOS transistors to reflect an output current that corresponds to the input voltage signal.
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