Title:
VARIABLE GAIN AMPLIFIER WITH IMPROVED POWER SUPPLY NOISE REJECTION
Document Type and Number:
WIPO Patent Application WO/2017/083052
Kind Code:
A3
Abstract:
A voltage gain amplifier (VGA) configured to have reduced supply noise. The VGA includes first resistor, first FET, and a first current-source coupled between first and second voltage rails. The VGA includes second resistor, second FET, and second current-source coupled between the voltage rails. A variable resistor is coupled between the respective sources of the first and second FETs. Variable capacitors are coupled between the first or a third voltage rail and the sources of the first and second input FETs, respectively. If capacitors are coupled to the first voltage rail, noise cancellation occurs across the gate-to-source voltages of the FETs if an input differential signal applied to the gates of the FETs is derived from a supply voltage at the first voltage rail. If capacitors are coupled to the third rail, supply noise is reduced if the supply voltage at the third rail is generated by a cleaner regulator.
Inventors:
YUAN XIAOBIN (US)
NATONIO JOSEPH (US)
BARTHOLOMEW KEVIN ROBERT (US)
PRASAD MANGAL (US)
NATONIO JOSEPH (US)
BARTHOLOMEW KEVIN ROBERT (US)
PRASAD MANGAL (US)
Application Number:
PCT/US2016/056905
Publication Date:
June 15, 2017
Filing Date:
October 13, 2016
Export Citation:
Assignee:
QUALCOMM INC (US)
International Classes:
H03K19/0175; H03F3/45
Foreign References:
| US20060066399A1 | 2006-03-30 | |||
| US8330537B1 | 2012-12-11 | |||
| US5856891A | 1999-01-05 | |||
| US20060197597A1 | 2006-09-07 |
Attorney, Agent or Firm:
FOUNTAIN, George (US)
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