Capacitive sensor conditioning IC raises the bar on accuracy, linearity, and temperature

ZMD AG (ZMDI) has expanded its family of capacitive sensor signal conditioning devices with the wide-dynamic-range ZSSC3123 IC.  The chip delivers 14-bit resolution and 0.25 % accuracy over a wide range of sensor capacitances and temperatures. Target applications include low-power battery-driven sensor applications, sensors for humidity, weight scales, load and compression sensing, as well as tension control.

The ZSSC3123 connects to microcontrollers but can also be used in stand-alone designs for transducer and switch applications.  The ZSSC3123 features an operating current as low as 60µA over the entire voltage range of 2.3V to 5.5V.  A built-in sleep mode lowers the current consumption to <1µA for temperatures up to 85°C.

The ZSSC3123 can be configured to interface with capacitive sensors from 0.5 to 260 pF, with sensitivity as low as 125 atto-Farads (aF) per digital bit. The part can be used in both single- and differential-input sensor configurations. The device offers a full 14-bit resolution for compensation of sensor offset, sensitivity and temperature. 

All calibration is digital and completed in one pass, eliminating the cost of laser trimming, and speeds up calibration of sensor modules in production. Programming and single-pass calibration of the capacitive sensor and the ZSSC3123 is accomplished through a standard PC environment using the ZSSC3123 kit and development tools. The kit includes a TSSOP14, development board, USB cable and calibration software.

At the standard supply voltage of 2.3 to 5.5 V, the device is accurate to 0.25 % over the -20 to +85°C range, and 0.5 % from -40 to +125°C. The ZSSC3123 part provides I²C and SPI interfaces as well as PDM or alarm outputs.

Pricing: Starts at 2.85 EUR, or USD 3.82, in volumes of 1k devices.  

Availability:  In production.

Datasheet: Click here.