Controller suggestion-Capsense with a Timer

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KaSa_1259906
Level 2
Level 2
First like received

Hello,

I am looking for a controller that has at least one capsense input, ADC input and a timer block.

The plan is to implement a touch switch with a momentary delay output. The user could adjust the potentiometer to adjust the delay in the sensor output from seconds to minutes.

What controller would you suggest that has those minimum requirement? Looking for an economical solution.

Thank you in advance.

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1 Solution

Hi KaSa_1259906​,

We recommend using 4000 S device for your application. You need to use the CapSense_ADC component (datasheet) that allows you to time multiplex capsense and ADC operation. The component takes care of time multiplexing and configuring the hardware for you. You can find the code example to do this here.

Regarding the delayed output, could you please provide more information on this requirement(timing diagrams/ flow chart)?

Regards,

Bragadeesh

Regards,
Bragadeesh

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8 Replies
MiNe_85951
Level 7
Level 7
Distributor - TED (Japan)
50 likes received 500 replies posted 50 solutions authored

Hi,

If that function is the main, it will be PSoC4 series.

When I confirm from cypress website,

I think CY8C4124PVI-442 is applicable.

As for the timer, four TC PWM blocks are installed.

CY8C4124PVI Datasheet URL

https://www.cypress.com/file/138651/download

If you have the following information, you can narrow it down further.

-- SAR ADC conversion speed : 806ksps or 1Msps?

-- Temperature grade : Automotive or Industrial?

-- Required GPIO

-- CapSense configuration : Do you need a gesture?

-- Approximate memory size

-- Package type : QFN ,QFP, CSP or SOP?

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Regards,

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PSoC 4000S is a solution too.

The CSD block in the PSoC 4000S can be used as a component named CapSense_ADC which has two functions CapSense and ADC alternately.  I understand that you are going to use the ADC for a potentiometer as a User-Interface.  So, the ADC does not require higher conversion frequency.

Regards,

Noriaki

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Thank you Noriaki, I have the CY8C4024LQI-S411 which is part of the PSoC 4000S series.

I was actually wondering if I used the ADC_CSD module will it interfere with the capsense module?

It would be great if I can find some sample codes on how I could go about creating a delayed output based on the ADC value.

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Hi KaSa_1259906​,

We recommend using 4000 S device for your application. You need to use the CapSense_ADC component (datasheet) that allows you to time multiplex capsense and ADC operation. The component takes care of time multiplexing and configuring the hardware for you. You can find the code example to do this here.

Regarding the delayed output, could you please provide more information on this requirement(timing diagrams/ flow chart)?

Regards,

Bragadeesh

Regards,
Bragadeesh
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Hello Bragadeesh,

Thank you for your reply and for the sample code.

Regarding the delayed output, the way the behavior is going to work is the following.

The user has the options:

1- Touching the cap sensor ( activating the capsense)  for an immediate momentary response at the output pin (output turns high) and when the finger releases, the output turns low.

Or delayed output meaning the user touches the sensor (after setting the delay potentiometer knob: 1 sec to 120 seconds) the output goes high and stays high for the delay amount.   

Any code help will be highly appreciated.

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Hi KaSa_1259906​,

I've attached a sample project based on your requirement. Please let us know if you have questions.

Regards,

Bragadeesh

Regards,
Bragadeesh
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Thank you Bragadeesh,

I will study it and come back if I have any questions.

Best Regards

Thank you MaMi. That's what I came up with however it's a bit overkill for my application. I was hoping to find something with smaller pin count.

I will only be using one output to drive a Mosfet, one ADC input and a capsense input. 

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