ZHCSH81 December 2017 PGA302
PRODUCTION DATA.
The PGA302 device implements a bridge offset cancel circuit at the input of the P GAIN in order to cancel large sensor bridge offsets. PGA302 achieves this by introducing a small current into one of the nodes of the bridge prior to the AFE gain. The selection of the offset is determined by the OFFSET_CANCEL register and the offset values are listed in Table 1.
OFFSET_CANCEL Value | Applied Offset Voltage [mV] |
---|---|
0x00 | 0 [OFF] |
0x01 | 3.65 |
0x02 | 7.3 |
0x03 | 10.95 |
0x04 | 14.6 |
0x05 | 18.28 |
0x06 | 21.9 |
0x07 | 25.55 |
0x08 | 29.2 |
0x09 | 32.85 |
0x0A | 36.5 |
0x0B | 40.15 |
0x0C | 43.8 |
0x0D | 47.45 |
0x0E | 51.1 |
0x0F | 54.75 |
Further the polarity of the applied offset can be changed by setting the OFFSET_CANCEL_SEL bit for positive offset or clearing the same bit for negative offset.