DRV8245H-Q1EVM: DIAG function fail

James Liu2

Part Number: DRV8245H-Q1EVM
Other Parts Discussed in Thread: DRV8434

Hello Team:

DRV8245H-Q1EVM

DIAG pin set to LVL1 (Fault reaction in Retry mode), Motor stall, nFAULT LED on, OUT1/OUT2 no power off, The motor is in a stalled state.

DIAG pin set to LVL2 (Fault reaction in Latch mode), Motor stall, nFAULT LED on, OUT1/OUT2 no power off, The motor is in a stalled state.

Is this state normal?

11 months ago

0 Keerthivasan Kumanan 11 months ago

TI__Expert 8615 points

Hello James,

Are you in PH/EN mode? How is your load configured? Can you send me your configuration of all your jumpers, so I can try to replicate the issue.

Best regards,

Keerthi Kumanan

0 James Liu2 11 months ago in reply to Keerthivasan Kumanan

Prodigy 50 points

DRV8245H-Q1EVM

MODE --> LVL1 PH/EN

SR --> LVL3

DIAG --> LVL2

IPROPI --> 1.0K

ITRIP --> LVL3

Thanks

0 Keerthivasan Kumanan 11 months ago in reply to James Liu2

TI__Expert 8615 points

Hello James,

Can you probe the IN1 and IN2 signals as well as monitor the output current on power on. Does your motor ever spin or is the nFault LED on to begin with? Does the fault clear when you press the clear fault button in the GUI?

Best,

Keerthi

0 James Liu2 11 months ago in reply to Keerthivasan Kumanan

Prodigy 50 points

1. I can probe the IN1 and IN2 signals

2. Motor can spin.

3. nFault LED on at stalled state. but DIAG function fail. It can not into Retry mode or Latch mode.

Thanks

0 Keerthivasan Kumanan 11 months ago in reply to James Liu2

TI__Expert 8615 points

Hi James,

What do you mean by it can not into Retry mode or Latch mode. So if I understood correctly, the motor spins for a bit and then when it stalls the nFault LED comes on. Can you check the voltage on VM as well for an undervoltage event?

Best regards,

Keerthi Kumanan

0 James Liu2 11 months ago in reply to Keerthivasan Kumanan

Prodigy 50 points

We conduct the DIAG function test, let the motor run, and use the equipment to cause the motor to stall, forming an nFault state. The correct state is when DIAG = LVL1 Retry mode, the motor encounters a stall, nFAULT LED on, the motor stops, and nFAULT LED off , and then re-energize to run, repeat until the stall situation is resolved; when DIAG = LVL2 Latch mode, the motor will stop when it encounters a stall, nFAULT LED is on, and the situation is relieved by the MCU.

The current problematic EVM has not achieved this function. When encountering a stalled situation, it has not reached the DIAG function, and has been in a stalled state, and the motor is powered on again.
thanks

0 Keerthivasan Kumanan 11 months ago in reply to James Liu2

TI__Expert 8615 points

Hello James,

It seems like it is an over voltage event:

This behavior seems normal as there is no direct way to detect stall in this driver IC. If you are looking for stall detection feature, then the DRV889 or the DRV8434 might be better suited for the application. If you want to implement with this IC, you could use current sense as described in this FAQ:

[FAQ] How to detect motor stall using current sensing - Motor drivers forum - Motor drivers - TI E2E support forums

Best regards,

Keerthi Kumanan