Defective Axp M5StickC (orange edition)?

ck

Hi there,

my M5StickC orange doesn't provide any 5V power on the "hat" pins. On the other side the 5V of the Grove port don't shut off on power-down. Even triggering EXT EN of AXP192 neither enable 5V on
"hat" nor disable 5V on Grove port on power-down. There isn't even a connection between those two 5V lines as shown in the diagrams.

Looks not like as this was intended, more like a bad hardware fault.

Is this a known issue? Is this customer fixable?

Thanks,
CK

Maxrom

I can't answer your question directly, but I do have a question which is kind of related to something you mentioned.

I have two M5StickC devices, one of which cuts power to the 5v GROVE pin when it's turned off. The other one keeps power to the 5v GROVE pin when turned off. Which is correct? I need the power at the GROVE connector to be shut off when the M5StickC is turned off (like you do as well I presume), so what's the situation here? Why do I have two devices behaving differently? Is one faulty? Has there been a hardware revision between them? I need to be able to cut power to the GROVE connector when the device is powered down.

Also, checking with a multimeter, I can see that when powered up, the GROVE power pin is showing 5v, but when powered off, it's showing 3.8v. Not sure what's going on with this.

world101

@ck, if you care to open up the case (you might not want to), you could check the soldering on the Extendable Socket ("hat") at the top to see if the connections are solid.

ck

Hi Maxrom,

@maxrom said in Defective Axp M5StickC (orange edition)?:

I can't answer your question directly, but I do have a question which is kind of related to something you mentioned.

I have two M5StickC devices, one of which cuts power to the 5v GROVE pin when it's turned off. The other one keeps power to the 5v GROVE pin when turned off. Which is correct? I need the power at the GROVE connector to be shut off when the M5StickC is turned off (like you do as well I presume), so what's the situation here? Why do I have two devices behaving differently? Is one faulty? Has there been a hardware revision between them? I need to be able to cut power to the GROVE connector when the device is powered down.

Same situation here. I need the GROVE connector to be shut off either on power off or on reconfiguration of the AXP192. I don't know if that came through a different hardware revision or if it is a production fault. Thanks for clarifying to me that you have got such a device and there are devices out there functioning as expected. I will buy another device from a different reseller.

Also, checking with a multimeter, I can see that when powered up, the GROVE power pin is showing 5v, but when powered off, it's showing 3.8v. Not sure what's going on with this.

Same here, it is not 5V but seems to be approx. battery voltage with enough power to supply heavy loads such as RFID readers.

ck

@world101 said in Defective Axp M5StickC (orange edition)?:

@ck, if you care to open up the case (you might not want to), you could check the soldering on the Extendable Socket ("hat") at the top to see if the connections are solid.

OK, I'll open it. Seems to be broken anyway, I've got the tools needed at hand.
I'll let you know. Thanks for your hint.

ck

@maxrom @world101 @m5stack

I opened the M5StickC and was kind of shocked of the obviously bad quality checks. 1. the 5V raiser pin to the hat connector wasn't soldered at all. 2. they are using a MP1541 switching regulator labeled as IB3GG to provide the 5V power. This is a heavy design fail and explains a) why the power never shuts off, but only drops to ~3,6V and b) why the batteries drain when shut off. Have a look at page 9 of the datasheet: https://www.mouser.de/datasheet/2/277/mp1541_r1.5-1398052.pdf
If the regulator is disabled power from the battery flows through L1 and D1 to the output. This is an explanation for another hardware revision using another switching regulator or placing a MOSFET before the IN pin triggert by the EN signal as well.

Cheers, CK