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DRV8842: it was burnt immediately when VM power on

Part Number: DRV8842

Hello,

we try to control a 24V dc motor with drv8842. In the test, we did not connect the motor.

When we connected VM to 24V power supply, the PIN 11(VM) got fired immediately. After burnt, no pin is short to GND.

It already burnt three pieces.

pin settings when power on:

I0~I4: H, Decay: open, nRESET: H, IN1: H, IN2: H

R76 = 2K, R78 = 10K

  • Hi M.Zhang,

    If you have damaged multiple devices with no load, please double check your layout.

    Also slowly power the device while monitoring the current.

    There are a couple of comments about the schematic:

    1) Please change the CP1/CP2 capacitor to 10nF per the datasheet
    2) Please change the VCP/VM capacitor to 100nF per the datasheet
    3) C60 is not required, and can be removed

  • Thank you for your reply.

    1) 2) it refers page 17 of datasheet, Figure 11. Example Layout. 

    3) it was removed already in the test.

    We will try your comments next week, waiting for new samples.

  • Hi M.Zhang,

    Unfortunately, the example layout is incorrect, although this capacitor values is probably not the cause.

    The pin description section is correct.

    Please let us know what you find.