• TI Thinks Resolved

TIDA-010042: TIDA-010042 MOSFETS for 40A

Intellectual 290 points

Replies: 12

Views: 153

Part Number: TIDA-010042

Can you please send me a board layout with the 40A CSD19531Q5A MOSFETS listed in the TIDA reference?

Along with part number where I can order them.

OR

swap the footprint with STP75NF75 MOSFET?

I wasn`t sure how to modify board layout

Thanks

  • Amar,

    Thanks for your interest in our FETs.

    If you are looking for an EVM to buy unfortunately this is not available, this design is a reference design in paper form only, it would have been validated on a single board but not made for public purchase.

    If you are looking to simply purchase the power MOSFET then samples can be purchased here:

    All the gerber files for this reference design can be found here, which include the MOSFET layout

    If you are looking for the MOSFET pcb footprint recommendation, this can be found on page 10 of the CSD19531Q5A datasheet.

    I hope this helps

    Best Regards

    Chris Bull

    www.ti.com/mosfet

  • In reply to Chris Bull:

    Would these MOSFETS be acceptable to use if we want the TIDA reference to handle 40A? 

    Has a 40A TIDA version been verified on a single board? If so, is there a board layout I can open in Altium? This would save me time in changing footprint and adjusting trace widths. I can access the 20A version but need a 40A version.

    Regards,

  • In reply to Amar Brar:

    Amar,

    I think we may have a MOSFET option from TI that may not mean changing the PCB too much.

    We have lower resistance MOSFETs like the 100V CSD19532Q5B or 80V CSD19502Q5B that I think could do the job. They will run quite hot and you will need to adjust the switching frequency down to say 50kHz, then also adjust the inductor to about 30uH to get acceptable ripple current. I am not sure if there is such high inductance high current available on the market, you will need to check.

    The CSD19502Q5B and the CSD19532Q5B should both fit on the same PCB footprint as the design.

    I ran some calculations of losses using this tool, as this is a 2 phase design I used the tool assuming 20A per phase:

    I came up with around 2.5-3Watts of losses @ 50kHz, this is about as much as this package can handle in a typical application, see article here for reference:

    Best Regards

    Chris Bull

    www.ti.com/mosfet

  • In reply to Chris Bull:

    I have added the STP75NF75 mosfets to the PCB design. Please let me know if there is any issue with using these before I order the board. I am planning to add a heat sink.

    Thanks

  • In reply to Amar Brar:

    Amar,

    I think it best you pursue this information from the manufacturer of the MOSFET, in this case ST Microelectronics.

    Best Regards

    Chris Bull

    www.ti.com/mosfet

  • In reply to Chris Bull:

    Ok I will, thank you for your help.

    Regards,

  • In reply to Amar Brar:

    What Vgs voltage is applied to each MOSFET?

    Thanks,

  • In reply to Amar Brar:

    Amar,

    I am assuming you are referring to TIDA-010042, this is dictated by Vcc applied to Vdd pin of the driver. In the schematic it shows 10V Vcc applied to the Vdd pin. So the gate drive on the MOSFET gate will be 10V.

    Absolute max rating for each MOSFET if the Vgs spec in the datasheet. For the case of the ST FETs and the TI FETs I suggested the max allowed Vgs voltage is 10V

    Best Regards

    Chris Bull

    www.ti.com/mosfet

  • In reply to Chris Bull:

     Ok, so the STP75NF75 should work.

    Thanks

  • In reply to Amar Brar:

    Amar,

    I mad an error in my previous statement and said max allowed for the TI and ST MOSFETs was 10V, this is incorrect, I should have said 20V. So a 10V gate drive if fine for any of them.

    Best Regards

    Chris Bull

    www.ti.com/mosfet