US 7,002,427 B2 · Filter trimming

Abstract

An adjustable phase shifter generates a phase shifted reference signal by introducing a phase shift in a reference signal. A phase detector identifies a phase difference between the reference signal and the phase shifted reference signal. A control signal generator generates a plurality of control signals, each of which causes the adjustable phase shifter to adjust a magnitude of at least one component value in the adjustable phase shifter. The phase shift introduced by the adjustable phase shifter is based at least partially on the magnitude of the at least one component value in the adjustable phase shifter. The control signal generator also selects one of the control signals, where the selected control signal causes the adjustable phase shifter to produce the phase shifted reference signal such that the phase difference attains a specified value. The analog filter adjusts a magnitude of at least one component value in the analog filter based at least partially on the selected control signal.

Claims20

Dependent claims

An integrated circuit, comprising:

an adjustable phase shifter operable to receive a reference signal and introduce a phase shift in the reference signal to produce a phase shifted reference signal;
a phase detector operable to identify a phase difference between the reference signal and the phase shifted reference signal;
a control signal generator operable to:
generate a plurality of control signals, each of the control signals capable of causing the adjustable phase shifter to adjust a magnitude of at least one component value in the adjustable phase shifter, wherein the phase shift introduced by the adjustable phase shifter is based at least partially on the magnitude of the at least one component value in the adjustable phase shifter;
and
select one of the control signals, the selected control signal capable of causing the adjustable phase shifter to produce the phase shifted reference signal such that the phase difference attains a specified value;
and
an analog filter operable to adjust a magnitude of at least one component value in the analog filter based at least partially on the selected control signal.

5 more elements

A method, comprising:

receiving information identifying a phase difference between a reference signal and a phase shifted reference signal, the phase shifted reference signal produced by an adjustable phase shifter introducing a phase shift in the reference signal;
generating a plurality of control signals, each of the control signals capable of causing the adjustable phase shifter to adjust a magnitude of at least one component value in the adjustable phase shifter, wherein the phase shift introduced by the adjustable phase shifter is based at least partially on the magnitude of the at least one component value in the adjustable phase shifter;
selecting one of the control signals, the selected control signal capable of causing the adjustable phase shifter to produce the phase shifted reference signal such that the phase difference attains a specified value;
and
providing the selected control signal to an analog filter, the selected control signal capable of causing the analog filter to adjust a magnitude of at least one component value in the analog filter.

2 more elements

A computer program embodied one computer readable medium and operable to be executed, the computer program comprising computer readable program code for:

receiving information associated with a phase difference between a reference signal and a phase shifted reference signal generated by an adjustable phase shifter;
generating a plurality of control signals, each of the control signals capable of causing the adjustable phase shifter to adjust a magnitude of at least one component value in the adjustable phase shifter, wherein a phase shift introduced by the adjustable phase shifter is based at least partially on the magnitude of the at least one component value in the adjustable phase shifter;
selecting one of the control signals, the selected control signal capable of causing the adjustable phase shifter to produce the phase shifted reference signal such that the phase difference attains a specified value;
and
providing the selected control signal to an analog filter, the selected control signal capable of causing the analog filter to adjust a magnitude of at least one component value in the analog filter.

2 more elements

Dependencies are inferred from the claim text.

Filter trimming

Life of this patent

Filter trimming

Life of this patent

Abstract

Claims20