Real-time adaptive hybrid BiST solution for low-cost and low-resource ate production testing of analog-to-digital converters
AssigneeQUALCOMM Incorporated
InventorSachin D. Dasnurkar
Life of this patent
Estimating the term…
Abstract
An integrated circuit configured to perform hybrid built in self test (BiST) of analog-to-digital converters (ADCs) is described. The integrated circuit includes an ADC. The integrated circuit also includes a BiST controller that controls the hybrid BiST. The integrated circuit further includes a ramp generator that provides a voltage ramp to the ADC. The integrated circuit also includes a first multiplexer that switches an input for the ADC between the voltage ramp and a voltage reference signal. The integrated circuit further includes feedback circuitry for the ramp generator that maintains a constant ramp slope for the ramp generator. The integrated circuit also includes an interval counter that provides a timing reference.
Claims24
A method for performing a hybrid built in self test (BiST) of analog-to-digital converters (ADCs), comprising:
- beginning testing on an ADC unit by a hybrid built in self test apparatus that comprises:
- a ramp generator that provides a ramp voltage to the ADC;
- and
- a first multiplexer that switches an input for the ADC between the ramp voltage and a voltage reference signal;
- determining whether a full coverage ramp test is enabled for the ADC unit;
- performing a full coverage ramp test on the ADC unit if a full coverage ramp test is enabled for the ADC unit;
- and
- performing a reduced coverage spot-check test on the ADC unit if a full coverage ramp test is not enabled for the ADC unit.
A method for performing a hybrid built in self test (BiST) of analog-to-digital converters (ADCs), comprising:
- beginning testing on an ADC unit;
- determining whether a full coverage ramp test is enabled for the ADC unit;
- performing a full coverage ramp test on the ADC unit if a full coverage ramp test is enabled for the ADC unit, wherein performing a full coverage ramp test on the ADC unit comprises:
- applying a ramp input to the ADC unit;
- observing the ADC unit output codes using a functional pattern;
- determining performance metrics for the ADC unit by an ATE;
- and
- extrapolating defective parts per million (DPPM) from a total number of units tested thus far;
- and
- performing a reduced coverage spot-check test on the ADC unit if a full coverage ramp test is not enabled for the ADC unit.
An apparatus for performing hybrid built in self test (BiST) of analog-to-digital converters (ADCs), comprising:
- means for beginning testing on an ADC unit by a hybrid built in self test apparatus that comprises:
- a ramp generator that provides a ramp voltage to the ADC;
- and
- a first multiplexer that switches an input for the ADC between the ramp voltage and a voltage reference signal;
- means for determining whether a full coverage ramp test is enabled for the ADC unit;
- means for performing a full coverage ramp test on the ADC unit if a full coverage ramp test is enabled for the ADC unit;
- and
- means for performing a reduced coverage spot-check test on the ADC unit if a full coverage ramp test is not enabled for the ADC unit.
An apparatus for performing hybrid built in self test (BiST) of analog-to-digital converters (ADCs), comprising:
- means for beginning testing on an ADC unit;
- means for determining whether a full coverage ramp test is enabled for the ADC unit;
- means for performing a full coverage ramp test on the ADC unit if a full coverage ramp test is enabled for the ADC unit, wherein means for performing a full coverage ramp test on the ADC unit comprises:
- means for applying a ramp input to the ADC unit;
- means for observing the ADC unit output codes using a functional pattern;
- means for determining performance metrics for the ADC unit by an ATE;
- and
- means for extrapolating defective parts per million (DPPM) from a total number of units tested thus far;
- and
- means for performing a reduced coverage spot-check test on the ADC unit if a full coverage ramp test is not enabled for the ADC unit.
Dependencies are inferred from the claim text.