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LM74610-SQEVM: LM74610-SQEVM for 24V <-> GND (reverse polarity protection)

Part Number: LM74610-SQEVM
Other Parts Discussed in Thread: LM74610-Q1, LM74700-Q1, LM74700EVM

Hello, what would be necessary to have a reverse polarity protection of 24V for the LM74610-SQEVM? I have this device here but it is only ratet for +12V to -20V. I would need to have protectet 24V and GND against each other. Which components do I have to change?

  • Hello,

    LM74610 device can work upto -40V and 40V.

    For the EVM to work, TVS at the input needs to be modified to suit the 24V reverse polarity protection.

    TVS D1_1 needs to be rated as per the maximum voltage seen in the 24V rail, 33V rated TVS would be good.

    TVS D1_2 has to be atleast 24V rated or more, 28V TVS is better.

    Would you like to have a look at LM74700-Q1 in place of LM74610-Q1?

    Regards,

    Kari.

  • Hello Kari,

    thank you for the explanation.

    I will give it a try. After ordering and resoldering, I will give you some feedback and klick on "Solved".

    Can you tell me why I should have a look at the LM74700 instead? Do you mean the schematic of the LM74700EVM? Or do you think, the LM74700-Q1 itself is bether in my case?

    Kind regards,

    Max

  • Hello Maxim,

    LM74700-Q1 has a wider operating range than LM74610-Q1.

    LM74610-Q1 maximum rating is 42V across its cathode to anode, but LM74700-Q1 has 75V absolute maximum ratings.

    Depending on the maximum reverse voltage (after clamping), either LM74700 or LM74610 can be chosen.

    Is this for automotive application? 24V reverse battery protection is discussed in detail in application section of datasheet.

    Regards,

    Kari.

  • Hello Kari,

    thank you for the informations.

    I`ll give the lm74700 a try, as this case is described in detail in the datasheet.

    It is not for automotive use. It is for industrial use (24V DC). It is just to prevent damage if someone plugs the device the wrong way.

    Regards,

    Max

  • Hello Kari,

    Just wanted to let you know - the tested Version with the Diodes you recommended was sucessfull. Thank you for your help and efford!

    Regards,

    Max