CY8CMBR3102 problem

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Anonymous
Not applicable

Hello

   

I am trying to build a proxy sense application using a CY8CMBR3102.

   

Although what i find is that there is a lot of toggling on the output pin even when my hand is not near the sensor.

   

Although the above information is quite vague and incomplete, please bear with me till i lay hands on the programmer.

   

(The existing board is designed by someone else and he had programmed it, and i dont have his project file with me )

   

What i would expect from the community is some early guidance like few do's and don'ts , or some information sharing regarding kick-starting the development with this part.

   

If you can share anything please do..

   

i will be back with some more info later

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1 Solution
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Welcome in the forum!

   

There are some videos to watch regarding CapSense. Take your time...

   

 

   

Bob

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4 Replies
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Welcome in the forum!

   

There are some videos to watch regarding CapSense. Take your time...

   

 

   

Bob

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Anonymous
Not applicable

Hello Bob

   

Apologies for the late reply since i was pre-occupied with other higher priority things.

   

With your helpful advice , i made a sensor board (attached the layout as pdf). This is a single layer board having ground mesh encompassing the sensor plane (as you can see from the pdf)

   

I connect the programmer and program the CY8CMBR3102, with the EZCLICK with settings as attached.

   

I have a capacitive un-isolated power supply to power the entire system.

   

(While programming i use another power supply, which is a regular PSU).

   

Now , when i disconnect the programmer and run the Board on its own, there is auto toggling of my output even when there's no obstruction in any form near the sensor.

   

Once the programmer is connected the system works absolutely fine.

   

I went a step ahead to program the distance of proxy sense.I connected a microcontroller to the I2C pins, and measure a variable voltage and program the Proximity Threshold Register at 0x35 with a value corresponding to 31-200  for a Voltage of 0-5v.

   

I constantly read 5 registers starting at 0x35, to simulate the 'programmer connected' condition

   

But the auto toggling wont stop.

   

I am out of ideas at the moment.

   

Any help will be welcome and appreciated.

   

Thanks and regards

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Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Looks as if the power supply is noisy. Measure with a scope the board connected to the supply VCC, Scope set to AC @20mV/div and look for noise and ripple.

   

 

   

Bob

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Anonymous
Not applicable

It seems i have identified the problem.

   

The Line and Neutral wires were reversed while coming on the board.When they are correct, there's no toggling whatsoever!

   

Although i am unable to understand why would that create a problem?

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