Cypress CapSense CY8C20x36 Guia do Utilizador

Getting Started with CapSense® Document No. 001-64846 Rev.*I Cypress Semiconductor 198 Champion Court San Jose, CA 95134-17

10 Document No. 001-64846 Rev. *I Getting Started with CapSense® 2. CapSense Technology Cypress‘s CapSense controllers use changes in capaci

Getting Started with CapSense® Document No. 001-64846 Rev. *I 11 2.1.2 Mutual-Capacitance Mutual-capacitance uses a pair of pins and measures

12 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 2-4. CapSense System Equivalent Model With a finger on the sensor surf

Getting Started with CapSense® Document No. 001-64846 Rev. *I 13 Figure 2-5. Sensing Algorithm Output 2.3.3 CapSense with Sigma Delta Modulator

14 Document No. 001-64846 Rev. *I Getting Started with CapSense® The CY8C20xx6A/AS/H family of CapSense controllers uses a single exter

Getting Started with CapSense® Document No. 001-64846 Rev. *I 15 Figure 2-8. CSA_EMC Block Diagram CxisensorSingle Slope ADCPrecharge ClockCmodHig

16 Document No. 001-64846 Rev. *I Getting Started with CapSense® 2.4.2 Signal-to-Noise Ratio (SNR) Signal is a generic engineering term

Getting Started with CapSense® Document No. 001-64846 Rev. *I 17 measurement. The difference count should not be used in the measurement of S

18 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 2-10. Different Noise Levels in Design A and B Being Compensated Automat

Getting Started with CapSense® Document No. 001-64846 Rev. *I 19 product. SmartSense_EMC with superior noise immunity is well suited and

Copyrights 2 Document No. 001-64846 Rev. *I Getting Started with CapSense® Copyrights © Cypress Semiconductor Corporation, 2010-2013. The infor

20 Document No. 001-64846 Rev. *I Getting Started with CapSense® 2.5.1.2 Matrix Buttons In applications requiring a high number of buttons such

Getting Started with CapSense® Document No. 001-64846 Rev. *I 21 Figure 2-15. Linear Slider 2.5.2.2 Diplexed Sliders In a diplexed slider, each C

22 Document No. 001-64846 Rev. *I Getting Started with CapSense® 2.5.2.3 Radial Sliders Radial sliders are similar to linear sliders in

Getting Started with CapSense® Document No. 001-64846 Rev. *I 23 2.6 Sensor Construction 2.6.1 Field Coupled via Copper Trace (PCB) Figure 2-19

24 Document No. 001-64846 Rev. *I Getting Started with CapSense® Features of a design based on springs/gaskets/foam:  Electrical field couple

Getting Started with CapSense® Document No. 001-64846 Rev. *I 25 Figure 2-21. LED Sourcing and Sinking Configuration CapSense ControllerVDDCapSense

26 Document No. 001-64846 Rev. *I Getting Started with CapSense® 2.7.1.1.4 LED Fading By gradually changing the duty cycle between LED states,

Getting Started with CapSense® Document No. 001-64846 Rev. *I 27 The linear brightness levels are transferred to exponential duty cycle values usin

28 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 2-28. Implementing LCD Feedback with CapSense on CapSense Plus 2.7.2

Getting Started with CapSense® Document No. 001-64846 Rev. *I 29 2.7.3 Audible Feedback Audible feedback for CapSense buttons is implemented usi

Getting Started with CapSense® Document No. 001-64846 Rev. *I 3 Contents 1. Introduction ...

30 Document No. 001-64846 Rev. *I Getting Started with CapSense® Rearranging the equation gives the following result:    

Getting Started with CapSense® Document No. 001-64846 Rev. *I 31 2.8 Water Tolerance Capacitive touch sensing is effective in applications where

32 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 2-33. Two-Layer Stack-up of a CapSense Board Four-layer designs are an

Getting Started with CapSense® Document No. 001-64846 Rev. *I 33 3. Design Considerations When designing capacitive touch sense technology

34 Document No. 001-64846 Rev. *I Getting Started with CapSense® 3.1.2 Overlay Thickness Sensitivity is inversely proportional to overlay thic

Getting Started with CapSense® Document No. 001-64846 Rev. *I 35 Table 3-3. Overlay Material Dielectric Strength Material Breakdown Voltage (V/mm)

36 Document No. 001-64846 Rev. *I Getting Started with CapSense® 3.2.2 Redirect If your product is densely packed, it may not be possible to p

Getting Started with CapSense® Document No. 001-64846 Rev. *I 37 3.3 Electromagnetic Compatibility (EMC) Considerations EMC is related to the gen

38 Document No. 001-64846 Rev. *I Getting Started with CapSense® ground flood is not recommended within 1 cm of CapSense sensors or traces due

Getting Started with CapSense® Document No. 001-64846 Rev. *I 39 Figure 3-8. Proper Current Loop Layout CapSense SensorCapSensemCGROUND FILLCONNECT

4 Document No. 001-64846 Rev. *I Getting Started with CapSense® 2.8 Water Tolerance ...

40 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 3-10. Impact of Slew Rate on Emissions The CapSense sensing methods use

Getting Started with CapSense® Document No. 001-64846 Rev. *I 41 3.4 Software Filtering Software filters are one of the techniques of dealing wit

42 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 3-13. Average Filter Noise (16 Samples) UnfilteredFilteredUnfilteredFilt

Getting Started with CapSense® Document No. 001-64846 Rev. *I 43 Figure 3-15. IIR Filter Step Response The general equation for a first-order IIR

44 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 3-17. IIR Filter Finger Touch UnfilteredFilteredUnfilteredFiltered For m

Getting Started with CapSense® Document No. 001-64846 Rev. *I 45 Figure 3-19. Median Filter (16-sample) Finger Touch For more information about

46 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 3-20. Jitter Filter Applied to Noisy Centroid Data UnfilteredFiltered 3

Getting Started with CapSense® Document No. 001-64846 Rev. *I 47 Figure 3-22. Jitter Filter for Button Finger Touch UnfilteredFilteredUnfilteredFil

48 Document No. 001-64846 Rev. *I Getting Started with CapSense® active state (scan all sensors, update all baselines, check if any sensor is in

Getting Started with CapSense® Document No. 001-64846 Rev. *I 49 Figure 3-24. Recommended: Port Isolation for Communication, CapSense, and LEDs Th

Getting Started with CapSense® Document No. 001-64846 Rev. *I 5 4. CapSense Product Portfolio ...

50 Document No. 001-64846 Rev. *I Getting Started with CapSense® The example in Figure 3-26 achieves good isolation, but it has a bad pin assign

Getting Started with CapSense® Document No. 001-64846 Rev. *I 51 3.7 PCB Layout Guidelines In the typical CapSense application, the capacitive se

52 Document No. 001-64846 Rev. *I Getting Started with CapSense® Button diameter can range from 5 mm to 15 mm, with 10 mm being suitable for the

Getting Started with CapSense® Document No. 001-64846 Rev. *I 53 3.7.8 Trace Routing Route sensor traces on the bottom layer of the PCB, so that

54 Document No. 001-64846 Rev. *I Getting Started with CapSense® Another approach to reducing crosstalk is to slow down the rising and falling e

Getting Started with CapSense® Document No. 001-64846 Rev. *I 55 Figure 3-37. Recommended Button and Slider Layout Bottom Layer 3.7.12 Shield El

56 Document No. 001-64846 Rev. *I Getting Started with CapSense®  Slow the edges of the shield waveform  Reduce the slew rate of shield ele

Getting Started with CapSense® Document No. 001-64846 Rev. *I 57 4. CapSense Product Portfolio Cypress‘s CapSense controller solutions are

58 Document No. 001-64846 Rev. *I Getting Started with CapSense® 4.1.3 CapSense Plus (Programmable Solutions) Figure 4-1. CapSense Plus CapSen

Getting Started with CapSense® Document No. 001-64846 Rev. *I 59 5. CapSense Selector Guide 5.1 Selecting the Right CapSense Device Several

6 Document No. 001-64846 Rev. *I Getting Started with CapSense® 1. Introduction 1.1 How to Use This Guide This guide is an ideal starting

60 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 5-1. Device Selection Tree CapSense Family PortfolioCY8CMBR2044, CY8C20

Getting Started with CapSense® Document No. 001-64846 Rev. *I 61 Table 5-1. CapSense Sensing Method by Product Family Product Family CapSense Us

62 Document No. 001-64846 Rev. *I Getting Started with CapSense® Product Family CY8CMBR2044 CY8C201xx CY8C21x34/B CY8C20x34 CY8C20xx6A/H CY8C20

Getting Started with CapSense® Document No. 001-64846 Rev. *I 63 6. CapSense Migration Paths As a system evolves, it may require a Cap

64 Document No. 001-64846 Rev. *I Getting Started with CapSense® 6.4 Pin-to-Pin Compatibility When migrating from one device to another, PCB c

Getting Started with CapSense® Document No. 001-64846 Rev. *I 65 7. Resources 7.1 Website At the Cypress CapSense Controllers website, you

66 Document No. 001-64846 Rev. *I Getting Started with CapSense® Note CY3280-20x34 Universal CapSense Controller and CY3280-21x34 Univers

Getting Started with CapSense® Document No. 001-64846 Rev. *I 67 7.4.6 In-Circuit Emulation (ICE) Kits The ICE pod provides the interconnection b

68 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 7-1. PSoC Designer Device Editor 7.7 PSoC Programmer PSoC Programmer

Getting Started with CapSense® Document No. 001-64846 Rev. *I 69 7.8 I2C-to-USB Bridge Kit The CY3240-I2USB kit allows you to test, tune, and deb

Getting Started with CapSense® Document No. 001-64846 Rev. *I 7 Figure 1-1. Typical CapSense Product Design Flow 3. CapSense device selection based

70 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 7-4. MultiChart User Interface

Getting Started with CapSense® Document No. 001-64846 Rev. *I 71 7.10 Design Support Cypress has several support channels to ensure the success o

72 Document No. 001-64846 Rev. *I Getting Started with CapSense® 8. Appendix 8.1 Appendix A: Springs 8.1.1 Finger-Introduced Capacita

Getting Started with CapSense® Document No. 001-64846 Rev. *I 73  Influence of diameter on FTC Figure 8-3. FTC versus Spring Diameter 00,511,522,

74 Document No. 001-64846 Rev. *I Getting Started with CapSense® Figure 8-6 shows examples of footprints for springs. Do not place solid grounds

Getting Started with CapSense® Document No. 001-64846 Rev. *I 75 8.2 Document Revision History Revision Issue Date Origin of Change Description o

8 Document No. 001-64846 Rev. *I Getting Started with CapSense® Table 1-1. Cypress Documents Supporting Numbered Design Tasks of Figure 1-1 Figu

Getting Started with CapSense® Document No. 001-64846 Rev. *I 9 1.4 Document Conventions Convention Usage Courier New Displays file locations, us