Samsung Electronics Co., Ltd.

Sung-gi Yang

Won Yup Ko

Yeon-Kug Moon

Provided is a mixer including a mixing unit configured to mix high frequency data signals and local oscillation (LO) signals, generate first and second low frequency data signals, and output the first and second low frequency data signals to first and second output terminals, respectively; a common mode amplification unit coupled to the mixing unit, the common mode amplification unit configured to compare a common mode voltage of the first and second low frequency data signals and a predetermined reference voltage, the common mode amplification unit further configured to output a feedback signal at a control node based on the comparison; a first load transistor coupled to the first output terminal and the control node, the first load transistor configured to provide the first output terminal with a first load current corresponding to the feedback signal; a first calibration transistor unit connected in parallel to the first load transistor in order to calibrate an input impedance of the first output terminal; and a first current mirror unit coupled to the first calibration transistor unit, the first current mirror unit configured to discharge a first calibration current that is output from the first calibration transistor unit to prevent the first calibration current from entering the first output terminal.

Mixer used for direct conversion receiver

A complementary transconductance amplifier having a common mode feedback circuit includes a first-type transconductor, a second-type transconductor and a common mode feedback circuit. The first-type transconductor generates a first differential output signal pair in response to a differential input signal pair under the control of a first control signal. The second-type transconductor generates a second differential output signal pair in response to the differential input signal pair under the control of a second control signal. The common mode feedback circuit generates the second control signal in response to the first and second differential output signal pairs under the control of a common mode control signal.

Transconductance amplifier having common mode feedback circuit and method of operating the transconductance amplifier

A charge pump circuit capable of improving the matching and switching characteristics, charge current, and discharge current and reducing leakage current and a phase locked loop including the charge pump circuit. In one aspect, the charge pump circuit comprise a first current source for sourcing current to an output terminal of the charge pump circuit in response to first bias voltage, a first switching device which is switched in response to a first control signal and a pull-down device for pulling down the voltage of a connection node of the first switching device between the first current source in response to the first control signal. In another aspect, the charge pump circuit comprises a second current source for sinking current from the output terminal of the charge pump circuit in response to second bias voltage, a second switching device which is switched in response to a second control signal and a pull-up device for pulling up the voltage of a connection node between the second switching device and the second current source in response to the second control signal.

Growing community of inventors

Seongnam-si, South Korea

Sung-gi Yang