GPIO resistance of CapSense

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NaMo_1534561
Level 5
Level 5
Distributor - Macnica (Japan)
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Hello,

I refer the section of 5.3.2.2.1 Sense Clock Related Parameters.

it describe that the typical value of the GPIO resistance is 500 Ω.

Please tell me the spec of min/max of GPIO resistance.

If there is no specification about it, what % of error should I assume?

PSoC® 4 and PSoC 6 MCU CapSense® Design Guide

Document Number. 001-85951 Rev. *W

https://www.cypress.com/file/46081/download

Best Regards,

Naoaki Morimoto

PSoC® 4 and PSoC 6 MCU CapSense® Design Guide

Document Number. 001-85951 Rev. *W

https://www.cypress.com/file/46081/download

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1 Solution
Hari
Moderator
Moderator
Moderator
750 replies posted 500 replies posted 250 solutions authored

Hi NaMo_1534561

The internal GPIO resistance will vary for different devices and the value is provided to accommodate worst case scenario.

This value of 500 ohm is used for sense clock frequency calculation so that the CapSense sensors can charge and discharge completely. It is recommended to use 500 ohm as the series resistance value for calculation.

Thanks and regards
Harigovind

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2 Replies
Hari
Moderator
Moderator
Moderator
750 replies posted 500 replies posted 250 solutions authored

Hi NaMo_1534561

The internal GPIO resistance will vary for different devices and the value is provided to accommodate worst case scenario.

This value of 500 ohm is used for sense clock frequency calculation so that the CapSense sensors can charge and discharge completely. It is recommended to use 500 ohm as the series resistance value for calculation.

Thanks and regards
Harigovind

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NaMo_1534561
Level 5
Level 5
Distributor - Macnica (Japan)
100 replies posted 100 sign-ins 50 replies posted

Hello Harigovind-san,

I understand that there is no specification of min/max of GPIO resistance however it is provided to accommodate worst case scenario.

Best Regards,

Naoaki Morimoto

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