US 11,936,346 B2
Programmable gain low noise amplifier
Rahul Sharma, Bangalore (IN); Jagannathan Venkataraman, Bengaluru (IN); Sandeep Oswal, Bangalore (IN); and Visvesvaraya Appala Pentakota, Bangalore (IN)
Assigned to TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US)
Filed by Texas Instruments Incorporated, Dallas, TX (US)
Filed on Apr. 15, 2021, as Appl. No. 17/231,728.
Prior Publication US 2022/0337203 A1, Oct. 20, 2022
Int. Cl. H03F 3/19 (2006.01); H03H 11/04 (2006.01); H03M 1/12 (2006.01)
CPC H03F 3/19 (2013.01) [H03H 11/04 (2013.01); H03M 1/1245 (2013.01); H03F 2200/451 (2013.01)] 15 Claims
OG exemplary drawing
 
1. An amplifier circuit, comprising:
first and second amplifiers, each having an input and an output;
a first attenuation circuit, having an input and an output coupled to the input of the first amplifier;
a second attenuation circuit, having an input and an output coupled to the input of the second amplifier;
a first input capacitor, coupled between the input of the first attenuation circuit and an output of the second attenuation circuit;
a second input capacitor, coupled between the input of the second attenuation circuit and an output of the first attenuation circuit; and
control logic adapted to control the first and second attenuation circuits to apply a selected attenuation to a received signal at their respective inputs;
wherein each of the first and second attenuation circuits is a digital step attenuation circuit comprising:
a digitally controllable series capacitance; and
a digitally controllable shunt capacitance;
and wherein the control logic is adapted to control the digitally controllable series capacitance and the digitally controllable shunt capacitance.