Detection Circuit
AssigneesSanyo Electric Co., Ltd., Sanyo Semiconductor Co., Ltd.
InventorKazuyuki Kobayashi
Life of this patent
Estimating the term…
Abstract
A detection circuit includes: a control signal updating circuit configured to update a digital control signal for controlling drive of a sensor based on a clock having a predetermined frequency; a digital to analog converter configured to convert the digital control signal output from the control signal updating circuit to an analog control signal for driving the sensor; a comparator configured to compare a voltage level of a detection signal from the sensor which changes depending on the analog control signal with a reference voltage having a predetermined voltage level to output a comparison result signal; and a counter configured to count to measure a time period depending on the detection signal based on the comparison result signal output from the comparator and a clock having a predetermined frequency.
Claims8
A detection circuit comprising:
- a control signal updating circuit configured to update a digital control signal for controlling drive of a sensor based on a clock having a predetermined frequency;
- a digital to analog converter configured to convert the digital control signal output from the control signal updating circuit to an analog control signal for driving the sensor;
- a comparator configured to compare a voltage level of a detection signal from the sensor which changes depending on the analog control signal with a reference voltage having a predetermined voltage level to output a comparison result signal;
- and
- a counter configured to count to measure a time period depending on the detection signal based on the comparison result signal output from the comparator and a clock having a predetermined frequency.
A detection circuit comprising:
- a comparator configured to compare a voltage level of a detection signal from a sensor with a reference voltage to output a comparison result signal;
- a control signal updating circuit configured to update a digital control signal for controlling a voltage level of the reference voltage based on a clock having a predetermined frequency;
- a digital to analog converter configured to generate the reference voltage having a voltage level depending on the digital control signal output from the control signal updating circuit;
- and
- a counter configured to count to measure a time period depending on the detection signal based on the comparison result signal output from the comparator and a clock having a predetermined frequency.
A detection circuit comprising:
- a control signal updating circuit configured to update a digital control signal based on a clock having a predetermined frequency;
- a digital to analog converter configured to convert the digital control signal output from the control signal updating circuit to an analog control signal;
- a driving circuit configured to output a driving signal for driving a first or second sensor based on the analog control signal output from the digital to analog converter;
- a first selector configured to output the driving signal output from the driving circuit to either of the first or second sensor;
- a second selector configured to output a detection signal output from either of the first or second sensor;
- a comparator configured to compare the detection signal output from the second selector with a reference voltage having a predetermined voltage level to output a comparison result signal;
- and
- a counter configured to count to measure a time period depending on the detection signal based on the comparison result signal output from the comparator and a clock having a predetermined frequency.
Dependencies are inferred from the claim text.