Patent ID: 7298203

Claim:
An amplification system capable of reducing direct current (DC) offset in a signal, comprising: a first differential input terminal and a second differential input terminal, which receive a first input signal and a second input signal respectively; a first differential output terminal and a second differential output terminal; a first low pass filter, which is connected to the first differential input terminal to filter the first input signal to thus generate a first filtered signal; a first amplifier having a first input and a second input coupled to the first differential input terminal and the first low pass filter, respectively, and a first output and a second output coupled to the first differential output terminal and the second differential output terminal, respectively, in order to amplify the first input signal and the first filtered signal to thus generate a first amplified signal at the first output and the second output; a second low pass filter, which is connected to the second differential input terminal to filter the second input signal to thus generate a second filtered signal; and a second amplifier having a first input and a second input coupled to the second low pass filter and the second differential input terminal, respectively, and a first output and a second output coupled to the first differential output terminal and the second differential output terminal, respectively, in order to amplify the second input signal and the second filtered signal to thus generate a second amplified signal at the first output and the second output, whereby the first amplified signal is cross coupled to the second amplified signal at the first differential output terminal and second differential output terminal.