Patent ID: 6232842
Filing Date: 2001-05-15
Classification: H03F,H03K,H04B

Abstract:
An amplifying circuit converting a mono-polarity input signal into a bi-polarity signal and amplifying the same, the amplifying circuit comprising:a first amplifier amplifying said mono-polarity input signal, and differential-outputting the amplified result in the form of positive-phase output and negative-phase output;a center value generating part generating a center value of the positive-phase output and a center value of the negative-phase output of said first amplifier, and outputting the respective center values as a first and second center values; anda second amplifier having a function of amplifying a difference {(V.sub.S1 -V.sub.R1)-(V.sub.S2 -V.sub.R2)} between a difference (V.sub.S1 -V.sub.R1) of a first input signal (V.sub.S1) and a first reference signal (V.sub.R1) and a difference (V.sub.S2 -V.sub.R2) of a second input signal (V.sub.S2) and a second reference signal (V.sub.R2), wherein the first input signal is assigned the positive-phase output of said first amplifier, the first reference signal is assigned said first center value, the second input signal is assigned the negative-phase output of said first amplifier, and the second reference signal is assigned said second center value.