Method and apparatus for increasing the effective resolution of a sensor

摘要

Methods and devices for increasing a sensor (14) resolution are disclosed. In one example, a two measurement process is used. A first measurement is used to effectively measure across a full range (e.g. 0 to 5 VDC) of the sensor (14). This first measurement may identify the current operating point (82) of the sensor (14) (e.g. 3.5VDC). A second measurement may then be made to effectively measure across a sub-range (88) of the sensor (14) that encompasses the current operating point (82) of the sensor (14) (e.g. across a sub-range (88) of 3.0 to 4.0 VDC for a current operating point (82) of 3.5VDC). The gain of the amplifier (30) may be raised during the second measurement to produce a higher resolution measurement. In some cases, the first measurement may be used to determine an appropriate offset that may be applied so as to scale the amplifier (30) to the desired sub-range (88) of sensor (14) that includes the current operating point (82) of the sensor (14). In some cases, the two measurements may be used together to compute an effectively higher resolution measurement signal. In some cases, this may allow for a smaller and/or cheaper sensor (14) to be used, while still achieving good results.