MICROCONTROLLER CAPACITANCE MEASURING DEVICE FOR BUILT-IN COMPUTER MONITORING AND CONTROL SYSTEMS Russian patent published in 2019 - IPC G01R27/26 

FIELD: measuring equipment.

SUBSTANCE: invention relates to measurement equipment, in particular, to devices for measurement of physical values by capacitive sensors, and can be used in embedded computer control and monitoring systems. Microcontroller capacitance measuring device for built-in control and monitoring computer systems includes (drawing) resistor 1, capacitive sensor 2, resistor 3, reference capacitor 4, microcontroller 5, computer 6 and RC-filter 7. Capacitive sensor 2 and reference capacitor 4 are connected to common wire by first plates, second plates of capacitive sensor 2 and reference capacitor 4 are connected to first outputs of resistors 1 and 3, respectively, second leads of resistors 1 and 3 are connected to outputs of first and second pulse-width modulators (PWM) built into microcontroller 5 (in the drawing PWM not shown), second plates of capacitive sensor 2 and reference capacitor 4 are connected to first and second inputs of analogue multiplexer built into microcontroller 5 (analog multiplexer is not shown in the drawing), analogue multiplexer output is connected to analog comparator built into microcontroller 5 (analogue comparator is not shown in drawing), computer 6 is connected through digital serial interface to microcontroller 5, output of third PWM, built into microcontroller (in drawing the third PWM not shown) is connected to the RC-filter input, the output of which is connected to the non-inverting input of the analogue comparator. Computer can be a Raspberry Pi microcomputer.

EFFECT: high accuracy of conversion and broader functional capabilities of the device, owing to the possibility of using a more sophisticated algorithm for converting capacitance to binary code, as well as high computational and info-communication capabilities of the device by introducing a computer.

1 cl, 1 dwg