7 Replies Latest reply on Feb 23, 2011 10:55 PM by udayan.umapathi

    Minimizing current in hibernate mode of PSoC3

    wojtek.gajda

      I have started to using low power modes of PSoC 3 and i'm wondering how to minimize current consumption in hibernate mode.

         

      I am using CY8C3866LTI-068ES3 device, i have made blank project - without any components, i have changed some parameters such as:

         
            
      • disabled pll,
      •     
      • master clock changed to IMO (3MHz),
      •     
      • completly disable debugging port.
      •    
         

      On my PCB i have 3.3V connected to: Vdda, Vcca, Vddio0,  Vddio1,  Vddio2,  Vddio3,  Vddd,  Vccd

         

      The ground is connected to: Vbat, Vb, Vssb, Vssd, Ex_Pad

         

      All other pins are unconnected.

         

      The only two lines in my code are:

         

      CyPmSaveClocks(); //Save Clock configuration before entering Hibernate
      CyPmHibernate(); // put the device into hibernate mode

         

      When i measure current taken by PSoC 3 (after starting this program) it's about 100 uA - when in datasheet it says that it supouse to be about 200nA.

         

      I'm wondering where such big difference comes from?

         

      What can i change to minimize current consumption?

         

      I was testing with forcing some pins to be outputs in high impedance, some to inputs and etc. - but any such move leads to bigger current.

         

      I have also tried "Hibernate_WakeupWithPICU" (application note and example) - but the minimum current is the same (over 100uA).

         

      I have attached example project which takes 100uA.

         

      Thanks in advance for any help/hints.