Floating I2C pins?

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KeTr_333366
Level 1
Level 1

 Hi, I'm finishing up a prototype design using the PSoC4013.  I'm using the I2C pins for factory calibration with the MiniProg3 as an I2C bridge.  I read that the miniprog3 has the pullups, so they're not needed for communication.  I know its probably not advised, but will floating I2C pins cause any problems after leaving the factory, ie increased current draw, phantom communication etc?  Will executing a EZI2C_Stop() be enough to alleviate the problem?

   

Thanks,

   

Ken

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

I looked at the EZ code for stop, its not clear to me whether GPIO

   

is in fact put in a known state, and whgat state.

   

 

   

You could do your own GPIO register writes to force the pin state,

   

this ap note discusses how -

   

 

   

    

   

         

   

http://www.cypress.com/?rID=93401     AN86439 - PSoC® 4 - Using GPIO Pins

   

 

   

 

   

and restore the state prior to issue Ez_Start( ).

   

 

   

However I still advise you file a CASE and ask if the above is necessary, if so what

   

is the correct way to do this.

   

 

   

One other possibility, add pullups on the board.

   

 

   

Regards, Dana.

   

 

   

    

   

         

   

To create a technical case at Cypress -

   

 

   

www.cypress.com

   

“Support”

   

“Technical Support”

   

“Create a Case”

   

 

   

You have to be registered on Cypress web site first.

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KeTr_333366
Level 1
Level 1

 Hi Dana, Thanks for looking into this for me.  I thought about relaying out the PCB, but its a small board packed with parts already.  I thought the best option might be to disable the I2C pins after factory cal.  I'll submit a case and see what they say.

   

 

   

Thanks!

   

Ken

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

Glad to have been of assistance.

   

 

   

Regards, Dana.

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