CapSense Low Power Design. Current Comsumption is enough small ?

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Anonymous
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In my design, the battery (the capacity is 50mAh) is always feed into the the pSoC4 BLE.

   

When an user touch the device, the pSoC4 BLE should power on the system(other chips etc.). 

   

 

   

The  pSoC 4 BLE's capsense is periodically(1sec via WDT) check the user's touch. 

   

The Capsense Low Power Method is shown on page 64  http://www.cypress.com/?docID=50746

   

In this low power design, What is the current consumption ? 

   

In my case, It must be needed under 5 uA.  

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Bob_Marlowe
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Have a look at this example. I hope this explanation will help you.

   

 

   

Bob

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ETRO_SSN583
Level 9
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These might be useful to you as well -

   

 

   

    

   

         

   

http://www.cypress.com/?rID=78797     AN86233 - PSoC® 4 Low-Power Modes and Power Reduction Techniques

   

 

   

http://www.cypress.com/?rID=96072     AN90114 - PSoC® 4000 Family Low-Power System Design Techniques

   

 

   

    

   

          

   

http://www.cypress.com/?rID=110007     AN92584 - Designing for Low Power and Estimating Battery Life for BLE Applications

   

 

   

 

   

http://video.cypress.com/video-library/search/psoc+4+low+power/

   

 

   

 

   

Regards, Dana.

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Anonymous
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 Thanks for reply Bob & dana. 

   

 

   

 I expected that the Cypress developer team had a measured data already.  Because they recommended the low power method  on page 64  http://www.cypress.com/?docID=50746, therefore cypress might checked the current consumption. 

   

 

   

Anyway, now I'm writing the code to ckeck the power dissipation step by step. 

   

However, some troubles has occured at the first step.

   

My first step is measuring the deep-sleep current. In the case of no ble, no any other peripherals. 

   

 

   

The code is extremely simple as below. 

   

 

   

#include <project.h>

   

int main()

   

{

   

    CyGlobalIntEnable; 

   

    for(;;)

   

    {

   

        CySysPmDeepSleep(); // go to deep sleep

   

    }

   

}

   

/* [] END OF FILE */

   
        
   
        
   
    Results of current measurements.    
   
        
   
     case1. without  CySysPmDeepSleep();   
   
        
   
    12.7mA.    
   
        
   
     case2. with CySysPmDeepSleep();    
   
     1.48mA    
   
    The current measurement photo was attached.    
   
        
   
    What was wrong in my simple codes?    
   
    How can I achieve the several uA in the deep sleep mode?    
   
        
   
        
   
        
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ETRO_SSN583
Level 9
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Consider posting your project, makes life easier to troubleshoot.

   

 

   

“File”                                                             Creator

   

“Create Workspace Bundle”

   

 

   

Regards, Dana.

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Anonymous
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Thanks Dana, 

   

The Workspace Bundle was attached. 

   

Really simple project. no peripheral , no ble. Just there is main and while loop. 

   

 

   

p.s. I did't know how can make the workspace bundle file. At now, I know that. thanks again. ^^

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ETRO_SSN583
Level 9
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What board are you using ?

   

 

   

Regards, Dana.

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Anonymous
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my target board is CY8CKIT-042-BLE and the BLE chip is CY8C4247LQI-BL483. 

   

I attached the image of the board and current measurement. 

   

you can see the this photo -> http://www.cypress.com/?docID=53543 

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Anonymous
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Couple of points:

   

1) You have both ECO and IMO enabled in your project and your system is running on IMO. Your ECO is still enabled. You should stop it before going to Deep Sleep by 'CySysClkEcoStop()'. 

   

2) Your Debug Select option in project'sCYDWR nothing.cydwr -> Systems Tab is set to SWD. This setting allows debugging but also conumes power when measured from BLE Pioneer Kit. Set this to GPIO to allow correct current measurement.

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Anonymous
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Hi rRoit.

   

Thanks a lot. 

   

Following your guide, now I achieve 1.6uA. in deep sleep mode. 

   

 

   

at first,  I add 'CySysClkEcoStop(); before  CySysPmDeepSleep(); 

   

In this case, the  current  is 0.132mA. (1.48mA without CySysClkEcoStop()) 

   

An then finally  Debug Select -> GPIO. In this case, the current is  0.0016mA (1.6uA).

   

 

   

It's very good. 

   

Thanks again. 

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