Abstract: A common-mode feedback circuit includes an amplifying circuit, a biasing circuit connected with the amplifying circuit, and a feedback loop connecting the amplifying circuit with the biasing circuit. The feedback loop includes a first field effect transistor M1, a eighth field effect transistor M1B connected with the first field effect transistor M1, a tenth field effect transistor M2B and an eleventh field effect transistor MFB connecting the eighth field effect transistor M1B and the tenth field effect transistor M2B. The common-mode voltage value of the common-mode feedback circuit is adjusted by the eleventh field effect transistor MFB. The common-mode feedback circuit has the simple structure and is capable of achieving the common-mode feedback without the peripheral feedback circuit and the input reference voltage.

Abstract: A threshold voltage generating circuit includes a main control circuit and a biasing circuit connected with the main control circuit. The main control circuit includes a first switching element, a second switching element connected with the first switching element, a third switching element connected with the second switching element, and a first operational amplifier connected with the third switching element, wherein an output end of the first operational amplifier outputs a threshold voltage. The threshold voltage generating circuit can generate the more precise threshold voltage.