Patent ID: 11936346
Assignee: TEXAS INSTRUMENTS INCORPORATED
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 8:
9. An analog front end, comprising:
an analog-to-digital converter;
a digital downsampler, having an input coupled to an output of the analog to digital converter, and having in-phase and quadrature phase outputs;
an amplifier circuit, comprising:
first and second input terminals for receiving positive and negative input signals, respectively;
first and second gain stages, each having an input and an output, the outputs of the first and second gain stages coupled to inputs of the analog-to-digital converter;
a first digital step attenuation circuit, having an input coupled to the first input terminal and an output coupled to the input of the first gain stage;
a second digital step attenuation circuit, having an input coupled to the second input terminal and an output coupled to the second input of the first gain stage;
a first input capacitor, coupled between the first input terminal and an output of the second digital step attenuation circuit; and
a second input capacitor, coupled between the second input terminal and an output of the first digital step attenuation circuit; and
control logic adapted to control the first and second digital step attenuation circuits to apply a selected attenuation to a received signal at their respective inputs;

wherein each of the first and second digital step attenuation circuits comprises:
a digitally controllable series capacitance; and
a digitally controllable shunt capacitance; and
and wherein the control logic is further adapted to control the digitally controllable series capacitance and the digitally controllable shunt capacitance.