CCS/BOOST-DRV8711: BOOST-DRV8711 burn

Hi Luca,

Did you verify that the VM and GND were connected correctly, not inverted?

Please, note that this EVM was designed to interface with TI based Launchpads, whose 20 to 40 pin headers have peripheral requirements that other company MCU PCBs might not meet. Plese, verify the pins you utilize from the MCU PCB interface with the correct pins on the boosterpack.

Hi Hector

Of course VM was correctly connected since I'm able to get/set the driver configuration through the tiva SPI line. I have noted that the SPI is not active if VM is unpowered. And I have enabled the driver from the control register but at that moment the DRV8711 burn out.

regards

Hi Luca,

Did you verify the pins you are interfacing between the MCU PCB and the BOOST-DRV8711 are correctly selected and configured?

Hi Hector,

As I have stated in the previous post all working fine before enabling the driver.

Luca 

Hi Luca,

Have you tried to isolate if the issue is boosterpack related and not MCU PCB related by supplying enable externally and making sure the DRV8711 on the EVM is not getting damaged?

Hi Hector

I have disconnected the boosterpack from the launch pad, the launch pad seems to work properly and it is USB powered. If I try to power the boosterpack alone I have a short on the VM with respect GND.

Luca

Hi Luca,

If you are probing the on the boosterpack that you saw the burn occur on, then it makes sense that you measure a short from VM to GND if the device was damaged.

I suggest you order a second boosterpack for your testing. If possible, please share with me as much data as possible about your connections and your setup. I am in the blind over here in terms of your setup, so there might be something I am not aware of that might be critical.

Please, let me know. Thank you.

Hi Hector

Just this evening we receive two more kit that we have ordered some time ago. Now I have ten days holiday but when I'm back and I'm ready again I get in contact again whit you before next power up

regards

Hi Luca,

Sounds good. Please, keep me updated.

Hi Hector

I'm back!

I have to perform some test to see if the launch pad is Ok and after I'm ready to switch on again the driver. The main characteristics of motor winding are:

Phase resistance = 0.35 Ohm
Phase inductance = 0.7 mH
Nominal Current = 5,3A (But I will work at 2.5A)

Let me know if you have a suggested setting for the driver.

Regards

Hi Luca,

Alright, thanks for the motor information. For now, we jus want to power this up and not damage the driver. So, if you can, please follow the steps to power up the EVM as per user's guide without the motor connected. You can start by power up the EVM by itself, make sure nothing is off, then use the launchpad you indicated you are utilizing.

Make sure the firmware you are utlizing on that MCU LP is manipulating the correct pins for switching on the enable and there are no other pins turning on (when they should not) that interface to the motor driver EVM. You can do this by running the code up to the point where the EVM was damaged and probe the pins that interface from LP to boosterpack.

Hi Hector

I have powered the driver and the launch pad too, and with disconnected motor all is good. I have correct some mistake that I have in firmware:

• I reset the driver after I have exit the sleep mode (not before as it was)
• I keep the reset active for longer time about 50us
• I wait some time before setting up the driver register after reset is exited

I have noted that EXTSTALL bit seems negated because if I set it I have stall led light if I try to commnad some steps.

Now how I can go on?

Regards