DRV8837: Spikes in the simulation of DRV8837

Danilo A.

Part Number: DRV8837
Other Parts Discussed in Thread: DRV8838,

Hi Team,

Our customer noticed some spikes in the Orcad pspice simulation of DRV8837. He downloaded the Pspice model of DRV8837 from the product page. According to our customer,

I downloaded the model of "DRV8837" for pspice simulation. I connected the component in this why:

I need this component for inductive load a-coil of 3.5mF, the problem it's the voltage on the coil. The plot in the simulation shows a small "spikes" that happens every 22us as you can see in the picture I added. I don't know why are they happens if its because the setup or it something in the simulation. please tell me what is the problem and how can I fixed it?

I hope you can see the spikes where the cursor's placed and every 22us after that.

**(Top plot its the current and the bottom its the voltage)

Another picture only voltage: In addition I couldn't find a model for "DRV8838", are you have a model for that component?

Regards,

Danilo

over 1 year ago

0 Pablo Armet over 1 year ago

TI__Mastermind 37683 points

Hi Danilo,

Can you ask the customer to capture the IN1 and IN2 and the opposite OUT signal. Seeing these signals will help better understand what is going on.

Danilo A. said:
Another picture only voltage: In addition I couldn't find a model for "DRV8838", are you have a model for that component?

The DRV8838 and the DRV8837 are similar devices expect that the DRV8838 is the phase/enable interface variant. So the DRV8837 can still be used for evaluating the DRV8838.

Regards,

Pablo Armet

0 Danilo A. over 1 year ago in reply to Pablo Armet

TI__Mastermind 25505 points

Hi Pablo,

Thank you for your response. Please see the email of our customer below.

First thanks for your service, I'm sending the capture you asked for.

This is the link to the simulation file that I downloaded : https://www.ti.com/lit/zip/slvm958,

I have a problem sending the file with my changes but you can see the setup I did in the pictures that I sent you previously.

Regards,

Danilo

0 Pablo Armet over 1 year ago in reply to Danilo A.

TI__Mastermind 37683 points

Hi Danilo,

Thank you for relaying the information. I was able to confirm the results with my own simulation. There seems to be an unexpected behavior with the SPICE model. I tried various variations of the load (resistive only, higher/lower inductance, higher/lower resistance) but the spikes are present exactly in the same location. I will have to investigate this further as I don't have an explanation for this issue.

Regards,

Pablo Armet

0 Pablo Armet over 1 year ago in reply to Pablo Armet

TI__Mastermind 37683 points

Hi Danilo,

Right after sending my previous reply, I remembered I answered a similar E2E question in the past (https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/958753/drv8837-swiching-noise-in-drv8837-simulation?ReplyFilter=Answers&ReplySortBy=Answers&ReplySortOrder=Descending).

The spikes in the OUT pins is similar to what the customer is seeing. Unfortunately, at the moment we are unable to fix the model. I suggest ordering a DRV8837CEVM for the customer. They can do evaluations with the EVM.

Regards,

Pablo Armet

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DRV8837: Spikes in the simulation of DRV8837