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DRV8876: Samples

Part Number: DRV8876

Hello,

Is it possible to get 100 samples of the DRV8876RGTR?

If we are unable to get these parts in 2wk we will have to design out the part.  

Thanks!

  • Hattie,

    DRV8876RGTR is out of stock in TI sample room and other place.

    Let me check our planner to see if we can get some samples. If I don't have any update this week, I won't think we can get the samples in two weeks.

    Regards,

    Wang

  • Hello Wang, we were able to reserve parts due at mouser the 20th. Which fab makes these? Is there a email I could send you my schematic/layout for review?

  • Hi Hattie,

    I'm an application's engineer from the motor driver's group.

    I got your schematic files from another TI employee and reviewed it.

    The schematic looks good to me. You're using our recommended component values for the passive components. My one concern is regarding the VM supply voltage. The VM supply written in the schematic is 4.5V which is right on the Under-voltage lockout (UVLO) threshold. Where are you getting the VM supply from? A battery? Or constant power supply?

    The table below shows the max and min UVLO values. If the voltage is below this threshold, the device will trigger a UVLO fault and disable the outputs. There is some hysteresis in these values but a UVLO fault may be triggered if there is significant ripple in the VM line or if the VM voltage drops due to battery discharging or from large inrush currents. Have you tested the load driving at 4.5V using our EVMs?

     

    If possible, I recommend increasing the VM voltage to at least 5V to avoid UVLO faults.

    Let me know if there are any questions.

  • Thank you Pablo, this is great (and speedy) feedback. That VVM rising max is a concern. 

    We are using a boost from a lipo battery and I think we could bump the boost voltage to 5V without impacting other systems that are sharing the rail (LED driver, nothing sensitive.)

    I have tested using 4.5V with the EVM but using a power supply and not the boost/battery. I looked at the startup current. I was designing to motor max datasheet currents, actual required operating currents are much lower than than the system was designed to - I have an 650mAh battery and a 800mA boost (so 3.6W at 4.5V.) The motor is nominally operating at 0.34W, so ~75mA.  

  • We just received notice that the parts we were expecting from Mouser are not available. This puts us in a very difficult spot, as we have already released board for fabrication. I have a few questions - are there *any* parts or samples available you can help us with? Are you able to confirm that parts are set aside for mouser? What would you recommend as the closest in footprint size and compatibility with this part? It turns out we actually need a lower voltage and power than when we originally designed the part, so something with a lower voltage and current would be fine. 

    Thank you for any help you can provide. 

  • Hi Hittie,

    I have asked our planning and marketing team when new samples will be available. I will let you know as soon as I get a response. If the lead time is too long, we may have to look into alternative parts that can replace the DRV8876 with minimal effort from your end.

  • Thank you. Yeah, any suggestions would be helpful as we evaluate spinning the board. The layout is tight, so again, something lower voltage/lower power, same or similar package would be good. Cheaper. Also good.

  • Hi Hattie,

    I was made aware that a product marketing engineer from our team is talking with your assigned FAE regarding the availability of the samples you need. I will post to this thread once I hear back from the marketing engineer regarding the availability. 

  • Hi Hattie,

    While we wait to hear back about availability of this part. I can help in suggesting other alternative parts we have in stock right now. I do have a couple questions for you to help me narrow down the options:

    1. What is the voltage and current ratings you need for your application?
  • We are operating at 4.5V and I expect the current to remain under 600mA.

  • Thank you for the information. 

  • Hello Hattie,

    I talked to my colleague and it looks like we are in the process of getting samples to you. I will close this thread for now but feel free to reply if you need further assistance.