MaxSTM(SMT) Overheating | Roman Hujer, Не могли бы вы помочь? Или поделиться своей электронной почтой?


 

Hi,

I wanted to build my own 3D printed equatorial mount, so I decided to use 100:1 gear reduction motors for my RA/DEC axis. The system was pretty much the same as built by Roman Hujer.

I had MaxSTM (SMT) boards but I believe I've burnt all of them (processor gets the correct volts). The problem was faulty stepper driver which was drawing extra current. As soon as I'd connect the stepper driver, 3.3V voltage regulator would heat up and its dead!

My questions are:

  1. Can I order STM32 BlackPill (SMD) microcontroller online and resolder it to get the boards working?
  2. My motors are rated for 1.3A amperes. Can MaxSTM (SMT) support such motors? Should they work?

Motors: 42byg Stepper Motor 40mm Body Length With 3.71:1~139:1 Ratio Nema17 Planetary Gear Stepping Motor With Gearbox - Dc Motor - AliExpress

STM32: Asourcing Buy Microcontrollers Ic Ufqfpn-48 Stm32f411ceu6 - Buy Buy Stm32f411ceu6,Electronic Components Ufqfpn-48 Stm32f411ceu6,Ic Stm32f411ceu6 Product on Alibaba.com


Howard Dutton
 

On Mon, May 16, 2022 at 07:50 AM, Fleep wrote:
  • Can I order STM32 BlackPill (SMD) microcontroller online and resolder it to get the boards working?
Hand soldering a new MCU seems like a difficult task to me.

  • My motors are rated for 1.3A amperes. Can MaxSTM (SMT) support such motors? Should they work?
Yes.

Sorry things didn't go smoothly there.  I'd be sure to focus efforts on identifying the root cause of the failure to know what correction is really needed.

Is a bad stepper driver really to blame?
Does the 3.3V regulator still work?
Does the processor function at all?


 

I powered on board 3/4 and the processor died instantly, I couldn't understand anything. (Status LED won't turn on as well). The first thing that'd overheat before each board's death would be the 3.3V voltage regulator.

So I took out board 4/4 and along with soldering headers, I removed removed the 3.3V regulator and soldered a new one which I bought locally(Both had 1A rating).

Now this board worked fine, I had my finger on the processor all the time. I connected stepper driver one and it was good. As soon as I connected the second driver, it started to overheat rapidly. I mean very rapidly!

So I pulled that driver out and it was back to normal temp. I tried to limit the current by reducing Vref on driver and connected it again, it overheated! I pulled the driver out maybe a second late but before I could do that board was damaged.

Damaged in a way that it works fine, only the processor maintains high temperature of 80-90 degrees.

(I had 4 boards in total. Board 2/4 died when I connected an Asus 19V 45W wall brick, even though 5V voltage regulator hadn't been connected yet, a flash ran through the Status and Power LEDs, they turned on for a second and it was dead.) 

To answer your questions precisely:

  1. I think bad stepper driver is to be blamed.
  2. The 3.3V regulator which I bought locally work fine. The one that came pre-soldered they died every time.
  3. The processor for board 3/4 died in an instant. The processor for board 4/4 heats up.

IRUN Current = 600

TMC2130 Vref = 1.15

Also when the processor was fine, onstep app would not allow alignment, it'd say "Hardware Fault." And the status tab would show "Motor/Driver" fault.


 

Hand soldering a new MCU seems like a difficult task to me.

I can get it soldered professionally, can it fix the boards? 

:(


Howard Dutton
 

On Mon, May 16, 2022 at 09:17 AM, Fleep wrote:
I can get it soldered professionally, can it fix the boards? 
Obviously I can't say for sure.


 

On Mon, May 16, 2022 at 11:09 AM, Fleep wrote:

I powered on board 3/4 and the processor died instantly, I couldn't understand anything. (Status LED won't turn on as well). The first thing that'd overheat before each board's death would be the 3.3V voltage regulator.

So I took out board 4/4 and along with soldering headers, I removed removed the 3.3V regulator and soldered a new one which I bought locally(Both had 1A rating).

Now this board worked fine, I had my finger on the processor all the time. I connected stepper driver one and it was good. As soon as I connected the second driver, it started to overheat rapidly. I mean very rapidly!

So I pulled that driver out and it was back to normal temp. I tried to limit the current by reducing Vref on driver and connected it again, it overheated! I pulled the driver out maybe a second late but before I could do that board was damaged.

Damaged in a way that it works fine, only the processor maintains high temperature of 80-90 degrees.

(I had 4 boards in total. Board 2/4 died when I connected an Asus 19V 45W wall brick, even though 5V voltage regulator hadn't been connected yet, a flash ran through the Status and Power LEDs, they turned on for a second and it was dead.) 

To answer your questions precisely:

  1. I think bad stepper driver is to be blamed.
  2. The 3.3V regulator which I bought locally work fine. The one that came pre-soldered they died every time.
  3. The processor for board 3/4 died in an instant. The processor for board 4/4 heats up.

IRUN Current = 600

TMC2130 Vref = 1.15

Also when the processor was fine, onstep app would not allow alignment, it'd say "Hardware Fault." And the status tab would show "Motor/Driver" fault.

If you are using the TMC2130 in SPI mode, why are you setting the Vref at 1.15V?  It should be at 2.4V (or close to it), and then the software sets the IRUN current.


 

And, both drivers are TMC2130s?  Which version?  The Fystec v1.0 requires a special modification on the underside to enable SPI.


 

Actually I think I fried the drivers first (not my fault, it was a wall brick with some high capacitance) and then the drivers fried the boards. But now I will set Vref to max.


 

BTT TMC2130 v3.0


George Cushing
 

Sounds like a short. The regulator's short/thermal protection is kicking in soon after power up. Even the cheap high frequency DC-DC buck converters seem to have there safeguards.

Start with all the modules pulled and just the regulator and the power LED connected. If the reg. doesn't shut down, start adding modules until you find the fault. It may be in the module or in its header. I've found that excess solder can short adjacent female header pins under the plastic covers.