MDC04

The capacitive sensing chips MDC04 and MDC02 are highly integrated mixed-signal sensing ICs. The chips connect directly to differential capacitive plates near the target medium, and detect material composition by amplifying, digitally converting, and compensating for minute capacitance changes based on differences in dielectric constants of various substances. An on-chip high-precision 16-bit ADC provides a capacitance resolution of 0.1fF with linearity error less than 0.3%. Additionally, a built-in temperature sensing circuit with 0.5°C accuracy supports temperature compensation and other temperature sensing applications. MDC04 and MDC02 are 4-channel and 2-channel high-precision capacitance conditioning chips, respectively. Each channel measures the mutual capacitance between two electrodes. The programmable fixed measurement range is 0~119pF, and the programmable variable conditioning range is ±15.5pF; the chip can automatically search for the optimal range configuration. Flexible measurement modes are supported, including multi-channel measurement combinations, single-shot measurement, and periodic cyclic measurement. MDC04 supports both a digital single-wire interface and I²C, while MDC02 supports the digital single-wire interface only. The single-wire interface enables distributed sensing over long cables with multiple nodes. Compared to similar products available domestically and internationally, MDC04 and MDC02 offer advantages including wide measurement range, wide operating voltage, low power consumption, multiple interfaces, built-in temperature measurement, compact size, and low cost. Target applications include liquid level sensing in smart small appliances, water tank level monitoring, oil level detection, water immersion sensing, food/soil moisture content measurement, ice and frost detection, and displacement sensing.

Applications

• Smart small appliance liquid level
• Water tank level
• Oil level
• Water immersion sensing
• Food moisture content
• Soil moisture content
• Ice/frost detection
• Displacement sensing

Key features

• Configurable fixed measurement range: 0~19pF
• Configurable variable measurement range: ±15.5pF
• Auto-search for optimal range configuration
• Capacitance resolution: 0.1fF
• Linearity error: <0.3%
• Wide supply voltage range: 2.0V~5.5V
• Low power consumption: average 5.3μA
• Measurement speed: single-channel 3.3/5.5/10.5ms configurable (default: 10.5ms)
• Temperature accuracy: ±0.5℃ @0℃~50℃
• Operating temperature range: -55°C~125°C
• MDC04 I²C/1-Wire interface
• MDC02 1-Wire interface