Unlock instant, AI-driven research and patent intelligence for your innovation.

Measure the capacitance of a capacitive sensor with a microcontroller with an analog output for driving a guard ring

A microcontroller, capacitive technology, applied in the direction of electrical components, electronic switches, pulse technology, etc., can solve the problem of insufficient resolution or detection

Active Publication Date: 2017-09-29
MICROCHIP TECH INC
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, resolution or detection in conventional systems may not be sufficient when such sensors operate in high noise environments
[0005] In particular, parasitic capacitance can cause problems in many capacitive sensor applications

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Measure the capacitance of a capacitive sensor with a microcontroller with an analog output for driving a guard ring
  • Measure the capacitance of a capacitive sensor with a microcontroller with an analog output for driving a guard ring
  • Measure the capacitance of a capacitive sensor with a microcontroller with an analog output for driving a guard ring

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0047] Microcontrollers now include peripherals that enhance the detection and evaluation of capacitive sensors. According to an embodiment, capacitive voltage division (CVD) may be used to evaluate whether a capacitive touch element has been touched. According to another embodiment, a Charge Time Measurement Unit (CTMU) may be used to evaluate whether a capacitive touch element has been touched. According to another embodiment, a capacitive sensing module (CSM) may be used to assess whether a capacitive touch element has been touched. However, the resolution or capacitance change detection in such capacitive measurement systems may not be sufficient when the capacitive sensor associated with the capacitive touch element is operating in a high noise environment.

[0048] In particular, parasitic capacitance can cause problems in many capacitive sensor applications. Whenever the conductors adjacent to the sensor (or its connection to the microcontroller) are at a different vo...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

This disclosure describes a microcontroller (101b) that measures the capacitance of capacitive sensors (704a to 704d) that have guard rings (320) associated therewith. A guard ring is provided around each capacitive sensor plate and is charged to substantially the same voltage as that on the associated capacitive sensor plate. The guard ring reduces parasitic capacitance of the capacitive sensor plate caused by voltage potential differences between the capacitive sensor plate and adjacent circuit conductors, ground planes, and power planes. An analog output (726) is buffered (714) and coupled to an analog input that is coupled to the capacitive sensor plate and used to drive a guard ring voltage to substantially all of the capacitive sensor plate same voltage as above.

Description

[0001] Related patent applications [0002] This application claims "Microcontroller ADC with External Access to Analog Input Bus" filed October 7, 2011 by Zeke Lundstrum, Keith Curtis, Burke Davison, Sean Steedman, and Yann LeFaou. Access to the Analog Input Bus)"; which is hereby incorporated by reference for all purposes. technical field [0003] The present invention relates to analog-to-digital and frequency converters, especially for use in microcontrollers, and more particularly, to analog-to-digital and frequency converters for use by microcontrollers with capacitive touch detection capabilities. Background technique [0004] An object (e.g., a piece of metal, finger, hand, foot, leg, etc.) touching a capacitive sensor or approaching a capacitive proximity sensor changes some of its parameters, especially in devices built for use in, for example, human-machine interface devices (e.g., The capacitance value of the capacitor in the touch sensor in the keypad or keybo...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H03K17/96
CPCH03K17/962H03K17/9622H03K2217/960705H03K2217/960765
Inventor 齐克·伦德斯特鲁姆基思·柯蒂斯伯克·戴维森肖恩·斯蒂德曼雅恩·勒法尔
Owner MICROCHIP TECH INC