Back to results
US 12,375,051 B2Granted
Auto-calibration systems and methods for reducing amplifier offset
AssigneeMaxim Integrated Products, Inc.
InventorsEuan Patrick Murphy, Matthew Derrell Felder, Bryan Mo
Life of this patent
Estimating the term…
Abstract
Systems and methods reduce unwanted effects caused by mismatch in amplifier circuits having components that are trimmable during and post-production to minimize DC offset. Various embodiments of the invention trim out amplifier mismatch by determining trim codes for two or more phases of operation of an amplifier circuit and use those trim codes to determine a final trim code for use in regular operation.
Claims19
A method for self-trimming mismatch in amplifier circuits, the method comprising:
- determining a plurality of trim codes for two or more phases of operation of an amplifier circuit that comprises an amplifier, the plurality of trim codes are determined using steps comprising:
- connecting a first input of the amplifier to a first voltage divider circuit that comprises a first input passive circuit component and a first feedback passive circuit component;
- connecting a second input of the amplifier to a second voltage divider circuit that comprises a second input passive circuit component and a second feedback passive circuit component;
- and
- in a first calibration phase, in response to sensing a differential voltage between the first and second inputs, adjusting values for at least one of the first or second feedback passive circuit components to update the differential voltage to obtain a first trim code of the plurality of trim codes;
- swapping connections of the first and second input passive circuit components;
- and
- in a second calibration phase, in response to sensing the differential voltage, adjusting the values to update the differential voltage to obtain a second trim code of the plurality of trim codes;
- and
- using the plurality of trim codes to determine a final trim code.
7 more elements
A amplifier circuit comprising:
- an amplifier that receives a differential voltage at a first input and a second input;
- a first feedback passive circuit, and a second feedback passive circuit;
- a first input passive circuit component that is coupled to the first input and forms, together with first feedback passive circuit, a first voltage divider circuit;
- and
- a second input passive circuit component that is coupled to the second input and forms, together with second feedback passive circuit, a second voltage divider circuit,
- wherein at least one of the first or second feedback passive circuit components being adjusted, in a first calibration phase in response to sensing the differential voltage, to update the differential voltage to obtain a first trim code, and
- wherein in response to connections of the first and second input passive circuit components being swapped and the differential voltage being sensed, values for at least one of the first or second feedback passive circuit components being adjusted, in a second calibration phase, to update the differential voltage to obtain a second trim code.
4 more elements
Dependencies are inferred from the claim text.