Method and apparatus for cross-point detection
View Patent ↗A method and apparatus for cross-point detection in devices have been disclosed where each leg of a differential signal is compared to a reference voltage and time lags for each are noted in crossing the reference voltage and this information is used to identify characteristics of the differential signal.
1. A method comprising:
establishing a reference voltage;
receiving a differential signal having legs;
comparing each leg of said differential signal to said reference voltage;
noting a time each leg of said differential signal individually crosses said reference voltage denoted as reference crossings;
noting a time said legs of said differential signal cross with respect to each other denoted as differential crossings;
examining timing relationships of said reference crossings and said differential crossings;
identifying characteristics of said differential signal based on said examination;
establishing a time reference and a time hysteresis window around said time reference; and
determining if said differential crossings time is within said time hysteresis window.
2. A method comprising:
establishing a reference voltage;
receiving a differential signal having legs;
comparing each leg of said differential signal to said reference voltage;
noting a time each leg of said differential signal individually crosses said reference voltage denoted as reference crossings;
noting a time said legs of said differential signal cross with respect to each other denoted as differential crossings;
examining timing relationships of said reference crossings and said differential crossings;
identifying characteristics of said differential signal based on said examination;
establishing a voltage hysteresis window around said reference voltage;
establishing a time reference and a time hysteresis window around said time reference;
noting a voltage at said differential crossings;
noting a time at said differential crossings; and
determining if said differential crossings voltage is within said hysteresis window and if said differential crossings time is within said time hysteresis window.
3. A method comprising:
establishing a reference voltage;
receiving a differential signal having legs;
comparing each leg of said differential signal to said reference voltage;
noting a time each leg of said differential signal individually crosses said reference voltage denoted as reference crossings;
noting a time said legs of said differential signal cross with respect to each other denoted as differential crossings;
examining timing relationships of said reference crossings and said differential crossings;
identifying characteristics of said differential signal based on said examination;
noting a voltage at said differential crossings;
generating an average voltage for said voltage at said differential crossings; and
adjusting said reference voltage to said average voltage.
4. The method of claim 3 further comprising communicating said average voltage to a receiving device.
5. The method of claim 3 wherein said generating an average voltage is performed with an integrator.
6. The method of claim 5 wherein said integrator is a charge pump.