• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 62 subscribers
  • Views 294 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM5050-1-Q1: What are the functional differences between lm5050 and lm74700-q1?

SHENG YANG
Expert 1090 points
Part Number: LM5050-1-Q1
Other Parts Discussed in Thread: LM74700-Q1, , CSD17571Q2, LM5050-1

ALL HI！

What is the difference between lm5050 and lm74700-q1 in use function? Whether it can be used interchangeably. My use requirements are: 1. Prevent the reverse flow of power supply; 2. Prevent the reverse connection of power supply at the input end; 3. Be able to pass 10A forward current. If the demand is met, can both chips be realized? thank you!

  • 0
    TI__Guru 57737 points

    Hi Sheng,

    1. Both LM74700-Q1 and LM5050-1-Q1 can block reverse current.

    2. LM74700-Q1 has input reverse polarity protection (IRPP) integrated but LM5050-1-Q1  does not have this feature integrated. But, LM5050-1-Q1 along with a diode (D3) in the return path as shown below can be reused to achieve IRPP.

    3. Both these devices can drive an external FET or multiple FETs in parallel to pass 10A forward current.

    Are you looking to make a common layout for these devices and use them interchangeably ?

     

  • 0 in reply to Praveen GD
    Expert 1090 points

    HI!Praveen GD!

    There is no need to make a compatible design between the two. In the current design, I use lm74700-q1 and lm5050-1-q1. In order to optimize the design, I wonder whether it is necessary to use one material for lm74700-q1 and lm5050-1-q1. The current use demand is that lm74700-q1 has the reverse connection of the input power supply at the input end of the power supply, so there is no problem with using lm74700-q1, I refer to demo design to make lm74700-q1 drive two field tubes to meet the requirements of passing 10A. The lm5050-1-q1 is connected to the DC-DC output side to prevent the reverse flow of current.

    Does the field tube driven by lm5050-1-q1 have requirements for internal resistance? It is estimated that the current passing through 5A currently uses field tube csd17571q2, and the internal resistance is 20mo. Will the internal resistance affect the time when lm5050-1-q1 turns off the reverse current?

  • 0 in reply to SHENG YANG
    TI__Guru 57737 points

    Hi Sheng Yang,

    LM74700-Q1 offers both input reverse polarity protection and reverse current blocking which serves your 2 requirements on the board. So, you can replace LM5050-1-Q1 on your board with LM74700-Q1.

    Please refer to datasheet Mosfet selection guidelines for understanding the Rds(on) selection for a specific load current requirement.

    As the effective Rds(on) of the FETs is reduced, the reverse current required for the controller (LM74700-Q1 or LM5050-1) to detect it and turn OFF the FETs  increases. This is because the controller requires a fixed voltage (Vsd(rev)) across OUT-IN to detect a reverse current.

  • 0 in reply to Praveen GD
    Expert 1090 points

    Thank you！Praveen GD!