Precision measurements and calibrations for timing generators

A subsystem for use with a timing generator having an output driver at which a timing signal having timing pulses is output, the subsystem comprising:

• an RC filter that filters a timing signal having an expected duty cycle, which is output by the output driver, to produce a DC voltage having a magnitude indicative of an actual duty cycle of the timing signal;
• and
• an analog-to-digital (ADC) that is coupled to the RC filter and converts the DC voltage, which is produced by the RC filter and has the magnitude indicative of the actual duty cycle of the timing signal, to a digital value indicative of the actual duty cycle of the timing signal;
• a memory that stores a calibration table that can be used to at least one of calibrate the timing generator or calibrate a measurement made using the timing generator;
• a controller that controls the timing generator to modify the timing signal to have each of a plurality of different expected duty cycles, so that the RC filter and the ADC collectively produce a respective different digital value indicative of the actual duty cycle of the timing signal, for each of the different expected duty cycles;
• wherein the controller, for each of the plurality of different expected duty cycles, compares the digital value indicative of the actual duty cycle of the timing signal to an expected value corresponding to the expected duty cycle, and determines an error associated with the timing generator in dependence on results of the comparison;
• wherein the controller fills in a plurality of cells of the calibration table in dependence on the determined errors;
• and
• wherein the calibration table is used to at least one of calibrate the timing generator or calibrate a measurement made using the timing generator.

A system comprising:

• a controller;
• a timing generator controlled by the controller to produce a timing signal, which over time, is modified to have each of a plurality of different expected duty cycles;
• an RC filter that filters the timing signal having expected duty cycles to produce DC voltages having magnitudes indicative of actual duty cycles of the timing signal;
• and
• an analog-to-digital (ADC) that converts the DC voltages, which are produced by the RC filter and have the magnitudes indicative of the actual duty cycles of the timing signal, to digital values indicative of the actual duty cycles of the timing signal;
• a memory configured to store a calibration table that can be used to at least one of calibrate the timing generator or calibrate a measurement made using the timing generator;
• wherein the controller is configured to:
• control the timing generator to modify the timing signal to have each of a plurality of different expected duty cycles, so that the RC filter and the ADC collectively produce a respective different digital value indicative of the actual duty cycle of the timing signal, for each of the different expected duty cycles;
• compare the digital value indicative of the actual duty cycle of the timing signal to an expected value corresponding to the expected duty cycle, and determines an error associated with the timing generator in dependence on results of the comparison, for each of the plurality of different expected duty cycles;
• and
• store, within the calibration table stored in the memory, error values indicative of differences between expected values associated with the plurality of different duty cycles and respective digital values produced by the ADC in response to the timing signal being provided to the RC filter;
• and
• wherein the calibration table is used to at least one of calibrate the timing generator or calibrate a measurement made using the timing generator.