External power supply (3.3V) to the CY8CKIT-062-BLE board

[Jiabin]

Hi,

  I am using  CY8CKIT-062-BLE as the evaluation board for development.

  I have an external power management module with a battery, which can provide 3.3V and GND. I want to use this 3.3V to power supply the CY8CKIT-062-BLE board. Currently, I connect the 3.3V and GND to P6VDD and GND in J18, respectively. The system works normally, the BLE can also be found by cysmart.

  However, when I try to measure the power consumption through J8 jumper, I find a difference when I use my external 3.3V supply and use the kitprog-2 USB debug cable. Following is what I am doing and what I observed.

•  I only call "Cy_SysPm_DeepSleep(CY_SYSPM_WAIT_FOR_INTERRUPT)" in the for(;;) loop both in CM0 and CM4, power CY8CKIT-062-BLE with debugging USB, and measure current flow from J8 jump, it is showing 0.03 mA, showing the system successfully went into deepsleep mode.
• Then, I removed the debugging USB, and connect the external 3.3V and GND to P6VDD and GND pin in J18, the current flow from J8 jump is showing ~0.5 mA. It seems the system is still in deepsleep mode, however, some resources in the development board are consuming extra power.

  I am wondering what is the reason that I measured different power consumption when I power the board with external 3.3V. 

  Really appreciate it if anyone can give me any answer or hint!!!

  Thank you very much for your very kind help!!!

[Len_CONSULTRON]

Jiabin,

I have some questions to clear up some confusion and to see if there are any extra circuits attached to your CY8CKIT-062-BLE board.

Question #1:  You mention you measure the current through the J8 connector.  I'm assuming you have depopulated R23 the 0 ohm resistor between the pins of J8.

Question #2:  Do you have any addition circuits connected to the board not listed in your original post?   This might contribute to additional current consumption.

Question #3: Are any of the LEDs turned on?  Even though you said:

---

....  I only call "Cy_SysPm_DeepSleep(CY_SYSPM_WAIT_FOR_INTERRUPT)" in the for(;;) loop both in CM0 and CM4 ...

It is possible to configure the ports driving an LED into the ON state before going to sleep.

Question #4:  It appears at this time, your firmware doen't contain any proprietary information.  Can you share your project with the forum?  This would allow others like myself who have a CY8CKIT-062-BLE to reproduce your results.

[Jiabin]

Hi, Len @Len_CONSULTRON 

  Really appreciate your kind help!!!

  Following are my understanding of your questions.

 #1: According to the manual of  CY8CKIT-062-BLE board,  the R23 is not loaded initially (https://www.infineon.com/dgdl/Infineon-CY8CPROTO-063-BLE_PSoC_6_BLE_Prototyping_Board_Guide-UserManu... ). I checked the board I am using, there is nothing between two R23 pads.

#2 I did not connect any port of CY8CKIT-062-BLE board except P6.Vdd and GND.

#3 On the board, I do not observe any LED on. 

#4 Thank you very much for helping me confirm the firmware, I have attached the project.

Really really appreciate your help!!!!!!

Jiabin

[Len_CONSULTRON]

Jiabin,

I have confirmed on my Cy8CKIT-062-BLE board that I am also getting higher current consumption with battery powered than with USB (KitProg) powered.

USB (Kit Prog) = <50uA (my measuring device can't go below 50uA).

Coin cell (3.3V on P6_VDD) = ~ 200uA.

I followed the schematics to try to find the 'leakage' source.  Nothing conclusive.

There was about 0.2uA to 0.4uA current loss through R41 and R42.

I could not tell what if any current loss occurred on the P6_VDD outputs of U19 (Voltage monitor IC) and U6 (Reverse Protection IC).  These are ICs usually controlled by the KitProg CPU which is unpowered in the Coin cell case.

[Jiabin]

Hi, @Len_CONSULTRON 

  Thanks!!!!

  Really appreciate that you also tried the project!!!!

  Yes, this is really confusing, because ~200uA is many times than 50uA, which makes the battery life many times less.

  Do you have any idea in what way I should solve this problem?

  You are very professional!!! Are you an engineer of Infineon?

Jiabin

[Len_CONSULTRON]

Jiabin,

---

 Yes, this is really confusing, because ~200uA is many times than 50uA, which makes the battery life many times less.

---

This would be correct.

---

Do you have any idea in what way I should solve this problem? 

---

Well ... I'm not sure.

The CY8CKIT-062-BLE is a nice and useful evaluation board.  However it contains a number of additional circuits to help the customer evaluate the performance of the PSoC.  These extra circuits 'could' be a source of extra current leakage.

To minimize these potential effects I took your project and moved it to run on a CY8CPROTO-063-BLE.  This board has many less extra circuits on it.  I figured if I could 'solve' the extra current issue this might be the way to go.

Results:

USB (Kit Prog) = 12.78uA.

Coin cell (3.3V on P6_VDD) = 128uA.

You can see running  with a primary battery (CR2032) consumes 10x the amount of current in DeepSleep than USB KitProg power source.   This is not right.  However, I'm at a loss to explain these results.   Hopefully Infineon will comment on these results.

---

  You are very professional!!! Are you an engineer of Infineon?

---

Professional ... I try to be.   No.  I'm not an Infineon employee.  Just a long-time enthusiast.

[Jiabin]

Hi, @Len_CONSULTRON 

  Thanks!!!

  Your explanation makes sense, and is very informative!!!!

Sincerely, with full respect!

[Len_CONSULTRON]

Jiabin,

You're welcome.

Hopefully we've given Infineon enough information here to allow them to reproduce our results.  Hopefully they can shed some light why a battery-powered version would consume 10x the current then USB powered.

[Len_CONSULTRON · Accepted solution]

Jiabin,

I believe I found a source of 73uA current leakage for the battery powered configuration that doesn't appear in the USB powered configuration.

Here is the leakage source on the CY8CPROTO-063-BLE:

These VTARG resistors will consume 3.3V/(15K + 30K) = 3.3V/46K = 73uA

This leakage is there in the USB powered configuration but is not seen through the Current Measurement Header

On the CY8CKIT-062-BLE has similar VTARG monitoring.  However in the Battery powered configuration P5LP_VDD is 0V which doesn't enable U19 output therefore VTARG_MON = 0V.  Therefore, I still can't explain the additional current leakage.

[Jiabin]

Hi, @Len_CONSULTRON 

  Thank you very much for your information!

  And thank you very much for spending time helping check the schematic and verifying the experiment results!!!!

[Yugandhar]

Hello,

In CY8CKIT-062-BLE, external power supply should be connected via VIN connector J9 or J1. There are five different options to power the baseboard; Type-C USB connector (J10), External DC supply via VIN connector (J9/J1), Debug and trace header (J12, VTARG_IN), Program and debug header (J11), and LiPo battery header (J15). Both USB Type-C connector and VIN connector inputs are ORed using diode and the higher voltage among the two take precedence. Please refer to the kit guide for more information.

Thanks,
P Yugandhar.

[Jiabin]

Hi @Yugandhar ,

 Thank you for your reply!

 I already read the kit guide and the information about the external power supply is shown as following picture:

However, none of them can use a 3.3V power source. Do you have any idea which pin I should connect the external 3.3V to the board? Of course, except p6.Vdd. 

[Yugandhar]

Hello,

It is recommended to use the power supplies which mentioned in the CY8CKIT-062 Pioneer kit only. 

Thanks,

P Yugandhar. 

[Jiabin]

Thank you for your reply.