BOOSTXL-DRV8305EVM: SPI register show that VCPH_UVFL pin is fault

Savas PINAR

Part Number: BOOSTXL-DRV8305EVM
Other Parts Discussed in Thread: DRV8305

Hi everyone,

I designed DRV8305 boostxl myself for using with c2000 piccolo launchpad. I mentioned before about spi registers in instaspin_universal gui { https://e2e.ti.com/support/applications/motor_drivers/f/38/t/574580 }

I fixed this previous fault changing the related mosfet. But I have new one. In status register 0x01, VCPH_UVFL shows 1 which default is 0. I think the driver IC DRV8305 is responsible for this fault and I think changing it with new one. But before doing that, I want to ask if there is another responsible for this fault or another solution to this fault.

Thank you,

Savas

over 7 years ago

0 Rick Duncan over 7 years ago

TI__Guru** 114905 points

Hi Savas,

What is the voltage on the VCPH pin? It should be 8V or more above VM. If not, please determine the reason the VCPH voltage is not.

0 Savas PINAR over 7 years ago in reply to Rick Duncan

Intellectual 270 points

Hi Rick,

Thank you for return. I checked the VCPH pin voltage. My VM is 17 V and my VCPH is 27.2 V. Do you have another idea?
Thank you.

Savas

0 Rick Duncan over 7 years ago in reply to Savas PINAR

TI__Guru** 114905 points

Hi Savas,

Is EN_GATE set to a logic high during power up? If so, please clear the fault after power up and report if the fault remains cleared.

0 Savas PINAR over 7 years ago in reply to Rick Duncan

Intellectual 270 points

Hi Rick,

EN_GATE is set to logic high during power up. But, I dont understand 'clear the fault' advice. How can I do that? Doing that in GUI spi register tab?

Savas

0 Rick Duncan over 7 years ago in reply to Savas PINAR

TI__Guru** 114905 points

Hi Savas,

Please write to the CLR_FLTS bit in the IC Operation Register. This should clear the fault. If the fault does not return it could have been set during the power up procedure.

0 Savas PINAR over 7 years ago in reply to Rick Duncan

Intellectual 270 points

Hi Rick,
I have written to CLR_FLTS. But, fault returned.
Savas

0 Rick Duncan over 7 years ago in reply to Savas PINAR

TI__Guru** 114905 points

Hi Savas,

Did the fault return immediately? If not, what event triggered the fault?

Do you have a second board to try? Does it exhibit the same issue?

0 Savas PINAR over 7 years ago in reply to Rick Duncan

Intellectual 270 points

Hi Rick,

I will try with second board, but before this, I think maybe I am wrong with pcb layout design. Can you explain me what is the purpose of net-tie in the schematic of DRV8305 and how should I apply it my own design.

Thank you

Savas

0 Rick Duncan over 7 years ago in reply to Savas PINAR

TI__Guru** 114905 points

Hi Savas,

A Net-tie allows two nets with different names to be connected in the schematic. In the layout it is a piece of metal with different names on each side.

Using Phase A as an example, SL-A, SN1, and SP1 carry little current as compared to the path from R4 to the source of Q4. The width of the trace can be less.

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BOOSTXL-DRV8305EVM: SPI register show that VCPH_UVFL pin is fault