Sensor read out
US6924649B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 20, 2003 |
| Grant date | Aug 2, 2005 |
| Priority date | — |
| Expiry date | Jul 3, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R17/20
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A circuit and a method to measure continuously the resistance of variable resistors in series as e.g. potentiometers within a sensor, used for e.g. a joystick, has been achieved. The voltage across said sensor comprising any number of variable resistors is stabilized. A constant current source is providing a minimum current through said sensor. A variable current source is used to zoom variations of current through the sensor caused by variations of resistance of the sensor. Said variable current is mirrored and by measuring the voltage across a shunt resistor the total resistance of the sensor is identified. Using ports between each of the resistors, voltages can be measured representing the resistance of each of the variable resistors using known equations of voltage dividers. Any number of variable resistors can be used in the circuit invented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.