The ZMD31210 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 ZMD31210 is adjustable to many capacitive sensors with capacitances ranging from 2pF to 260pF and a sensitivity of 125aF/LSB to 1pF/LSB depending on the resolution, speed, and range settings (using 3-bit reference and 3-bit offset capacitances). 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 ZMD31210 and a specific sensor are mated digitally: fast, precise, and without the cost overhead associated with trimming by external devices or laser.
For quick and easy evaluation of the ZMD31210 and support for calibrating prototypes, ZMD offers the ZMD31210 development kit, which includes the development board, TSSOP14 samples, and software. Order using part number ZMD31210KIT.