Vital current sensor
View Patent ↗A system for sensing current that includes a processor and a current sensor coupled to the processor. The current sensor includes a sensor threshold value. The system also includes a current generator coupled to the current sensor. The current generator is operable to generate a test current signal defined by a time-varying linear function. The current sensor is operable to be coupled to an external current source and to output a sensor output signal based on a detected current to the processor. The processor is operable to determine a magnitude of the sensor threshold value based on the sensor output signal.
1. A system for sensing current, comprising:
a processor;
a current sensor coupled to the processor, the current sensor having a first sensor threshold value and a second sensor threshold value; and
a current generator coupled to the current sensor;
wherein the current generator is operable to generate a time-varying linear test current signal having a first value below the first sensor threshold value and a second value above the second sensor threshold value;
the current sensor is operable to be coupled to an external device and the current generator;
the current sensor is operable to output a sensor output signal to the processor, the sensor output signal being dependent on a first current associated with the current generator and a second current associated with the external device; and
the processor is operable to determine a time between a crossing of the first sensor threshold and a crossing of the second sensor threshold.
2. The system of claim 1 , wherein the sensor output signal comprises a pulse having a pulse width based on a magnitude of the first sensor threshold and a magnitude of the second sensor threshold.
3. The system of claim 1 , wherein:
the test current signal comprises a starting current value and an ending current value, and
the starting current value and the ending current value have opposite polarities.
4. The system of claim 1 , wherein:
the external device has at least one operating state; and
the processor is operable to determine the operating state based on the sensor output signal.
5. The system of claim 1 , further comprising a display connected to the processor and operable to display a status of the current sensor.
6. The system of claim 1 , wherein the current sensor is a Hall effect sensor.
7. The system of claim 1 , wherein the sensor output signal is a digital signal.
8. The system of claim 1 , wherein the processor is operable to generate an alert based on the time between the crossing of the first sensor threshold and a crossing of the second sensor threshold.
9. The system of claim 8 , further comprising a display operable to display the alert.
10. A method for sensing current, comprising:
applying a time-varying linear test current to a current sensor, the current sensor having a current sensor output being dependent on a current flowing through an external device and the test current, the current sensor having a first sensor threshold value and a second sensor threshold value;
determining a time between a crossing of the first sensor threshold and a crossing of the second sensor threshold.
11. The method of claim 10 , wherein:
the test current signal comprises a starting current value and an ending current value, and
the starting current value and the ending current value have opposite polarities.
12. The method of claim 10 , further comprising:
determining an operating state of the external device based on the sensor output signal.
13. The method of claim 12 , further comprising displaying the operating state.
14. The method of claim 10 , further comprising generating an alert based on the time between the crossing of the first sensor threshold and a crossing of the second sensor threshold.
15. The method of claim 14 , further comprising displaying the alert.
16. The method of claim 10 , wherein the sensor output signal is a digital signal.
17. The method of claim 10 , wherein the sensor output signal comprises a pulse having a pulse width based on a magnitude of the first sensor threshold and a magnitude of the second sensor threshold.
18. The method of claim 10 , wherein the current sensor is a Hall effect sensor.