The ZSSC3122AA2R cLite™ is a CMOS integrated circuit for accurate capacitance-to-digital conversion and sensor-specific correction of capacitive sensor signals. Digital compensation of sensor offset, sensitivity and temperature drift is accomplished via an internal digital signal processor running a correction algorithm with calibration coefficients stored in a non-volatile EEPROM. The ZSSC3122AA2R is configurable for capacitive sensors with capacitances up to 10pF and a sensitivity of 125aF/LSB. It is compatible with both single capacitive sensors (both terminals must be accessible) and differential capacitive sensors. Measured and corrected sensor values can be output as I2C, SPI, PDM, or alarms. The I2C interface can be used for a simple PC-controlled calibration procedure to program a set of calibration coefficients into an on-chip EEPROM. The calibrated ZSSC3122AA2R and a specific sensor are mated digitally: fast, precise, and without the cost overhead of trimming by external devices or laser.
Feature
- Maximum target input capacitance: 10pF
- Sampling rates as fast as 0.7ms @ 8-bit, 1.6ms @ 10-bit, 5.0ms @ 12-bit, 18.5ms @ 14-bit
- Digital compensation of sensor: piece-wise 1st and 2nd order sensor compensation or up to 3rd order single-region sensor compensation
- Digital compensation of 1st and 2nd order temperature gain and offset drift
- Internal temperature compensation reference (no external components)
- Programmable capacitance span and offset
- Layout customized for die-die bonding with sensor for low-cost, high-density chip-on-board assembly
- Accuracy as high as ±0.25% full-scale output @ -20 to 125°C, 3V, 5V, Vsupply ±10% (see data sheet for restrictions)
(Picture: Pinout)
