Da14683 Not coming out of sleep on internal RC timer

Does anyone know why the DA14683 would not come out of sleep mode?

We have a setup that from a hardware point of view is identical to the development daughter board DA14684 DB AQFN vD.  If we run the code on the daughter board powered on its own by a coin cell it goes to sleep and comes out on the 5seconds on 5 seconds off cycle we have set.

Running the same code on our board it works for a few cycles then stops. Totally baffled, help please.

  • Hi JeffKAllen,

    Thank you for posting your questions online.

    1, Which SDK version you are using?

    2, You can compare with the EVK schematic: https://www.renesas.com/us/en/document/sch/da14683-pro-development-kit-daughter-board-schematic-aqfn?r=1580551

    3, Does the customer board powered the same as EVK?

    4, You can share your schematic if it's possible.

    BR,

    JH_Renesas

  • Hi JeffKAllen,

    One more question, does the 5s wake up based on the timer or something?

    BR

  • Hi JH Thank you or quick response,

    1. The SDK version is 1.0.14.1081

    2. The schematic is at  https://www.dropbox.com/scl/fi/rwocxsxcz5hz7d5lmuu6v/Screenshot-2024-06-13-at-09.25.55.png?rlkey=jzv585dkm083ube290m8ogab2&dl=0 

    As far as i can see this is near enough identical to the EVK schematic

    3. The power is provided on VBAT and is from a 3.7V lithium battery

    4. The timer being used is the free RTOS timer provided in the SDK that we believe uses timer 1

    BR Jeff

  • Hi Jeff,

    Which sleep mode are you using.

    BR,

    JH_Renesas

  • Hi JH Extended sleep mode.

    We have yesterday done the following :

    On your EVK board put on the firmware to put the unit to sleep for 5 seconds wake for 5 seconds and power it from a power supply on VBAT at 3.8V, current consumption when awake is 1mA when asleep is 20uA which is all as it should be.

    We then put the same firmware on our board, the current consumption when awake is 2mA and when asleep goes up to 200uA, but it then never wakes up. 

    We therefore suspect a hardware issue, but we are certain it cannot be a build issue because we have built the same chip onto 3 different boards and get pretty much the same issue on all the boards

    I will send you the PCB layouts please could you take a look and tell me if this could be a layout issue, we have tried to follow your layout but there are minor differences.

    Thanks

    Jeff

  • Hi Jeff,

    I got updates from HW team:

    I have checked the schematic, and found nothing relevant for the issue.
    One item not related to issue has been found, please see last line in this comment. 
      
    Some questions to the customer: 

    • so, also at VBAT = 3.8 V from external power supply, the chip is not waking up after some time? 
    • what are the following rail voltages when the device is not waking up and the VBAT current is 200 µA? 
      VBAT V33 V18 V18p V14 V12
      ? V ? V ? V ? V ? V ? V
    • is the XTAL32K (Low Power Clock) running?  Please measure at the Xtal32K pins using a low capacitance probe. 
         
    • The one comment about the SCH: the LED D1 can not work as it's connected like in the schematic. 
        The LED1 pin of the DA14683 is an Open-Drain output. So the LED has to be connected to a supply, e.g. +3V3. 
        

    BR,

    JH_Renesas

  • The one comment about the SCH: the LED D1 can not work as it's connected like in the schematic. 
      The LED1 pin of the DA14683 is an Open-Drain output. So the LED has to be connected to a supply, e.g. +3V3. 

    We don't use this so not an issue but will note for future Thank you

  • Hi JH

    • what are the following rail voltages when the device is not waking up and the VBAT current is 200 µA? 
      VBAT V33 V18 V18p V14 V12
      ? V ? V ? V ? V ? V ? V

    Vbat is stable at 3.653

    V33 is stable at 3.25V

    V18 is stable at 1.795V

    V12 is stable at 1.15/1.17V, but drops when unit goes to sleep, when it comes back up after the time period it has a bit more ripple on it

    V14 varies depending on state from 1.3V to 1.4V

    V18P powers up to 1.8V on power up but then decays to about 0.45V and never comes back up.

    Another thing noticed is the power consumption. On power up while running current is 1.9mA approx, when sleep starts current drops to approx 200uA, but then after the 5 seconds sleep time the current goes back up to 1.14mA but the unit does not start up properly, seems it is timing during sleep but not able to power up correctly on trying to leave sleep mode.

    so, also at VBAT = 3.8 V from external power supply, the chip is not waking up after some time? 

    Correct when powered up from an external supply at 3.7 or 3.8V it does not wake up

    KR Jeff

  • Another thing noticed is the power consumption. On power up while running current is 1.9mA approx, when sleep starts current drops to approx 200uA, but then after the 5 seconds sleep time the current goes back up to 1.14mA but the unit does not start up properly, seems it is timing during sleep but not able to power up correctly on trying to leave sleep mode.

    Hi JH

    On the dev kit board the power consumption is is 1.2mA when running and 20uA when asleep with the same firmware, as with the above the power supplies measure similarly. However after going to sleep and wakinig up for the first time the power comes back to 900uA not 1.2mA

    KR Jeff