Patent ID: 7652531
Filing Date: 2010-01-26
Classification: H03F

Abstract:
1. An amplifier for making an input signal stronger, either manufactured in a printed circuit board (PCB) or an integrated circuit (IC) chip, comprising: a first stage amplifying module, which serves as a local trans-conductance amplifier, receiving a voltage signal from an external signal source as input and generating a current signal output; a second stage amplifying module, which serves as a local trans-impedance amplifier, receiving said current signal output from said first-stage amplifying module and a local feedback signal from a local negative feedback network, and outputting an amplified voltage signal; a third stage amplifying module, which serves as a voltage follower to provide current gain and acts as an output stage of said amplifier, receiving said amplified voltage output from said second stage amplifier and outputting final amplified signal with enough voltage and current amplitude to drive a load; said local negative feedback network, which are connected between input node of said second-stage amplifying module and output node of said third-stage amplifying module, receiving said final amplified signal of said third stage amplifying module, suppressing distortion that is generated by both said second-stage amplifying module and said third-stage amplifying module, and maintaining stability of said amplifier; and wherein said first stage amplifying module further receives an overall negative feedback signal from an overall negative feedback network which is connected between input node of said first-stage amplifying module and said output node of said third stage amplifying module and receives said final amplified signal of said third stage amplifying module, for further improving overall performance of said amplifier.