High Resolution Capacitive Readout Support for MEMS Sensors

Download MS3110 Datasheet

Operational Benefits

The Universal Capacitive Readout IC (MS3110) general purpose, ultra-low noise CMOS IC supports a variety of MEMS sensors that require a high resolution capacitive readout interface. The MS3110 requires only a single +5VDC supply and decoupling components. No additional components are required.

MEMS sensors such as accelerometers, rate sensors, as well as other sensors that can be modeled as variable capacitors require a readout electronic interface that can sense small changes in capacitance. The MS3110 is capable of sensing capacitance changes down to 4.0 aF/rtHz.

The MS3110 can interface to either a differential capacitor pair or a single  capacitive sensor. A high-level voltage output signal that is linear with full range of sense capacitance is provided. It also includes an on-chip capacitive DAC (up to 10pF) for initial differential adjustments and/or for quasi-differential operation with a dummy capacitor. The MS3110 has provisions for trimming the gain and output offset and bandwidth is user programmable as well as an on-chip EEPROM is provided to store trim and program settings.

Features

• Capacitance Resolution: 4.0aF/rtHz
• Sensor modes: single variable or dual differential variable
• On-chip dummy capacitor for quasi-differential operation and initial adjustment
• Gain and DC offset trim
• Programmable bandwidth adjustment 0.5 to 8kHz (9 steps)
• 2.25 VDC output for ADC reference/ratiometric operation
• Single supply of +5.0VDC
• On-chip EEPROM for storage of settings
• Available in 16-pin SOIC