• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 62 subscribers
  • Views 32 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.

LM74720-Q1: LM74720-Q1 Oring circuit using Two Inputs

Sanath P
Prodigy 90 points
Part Number: LM74720-Q1

Tool/software:

Hi TI,

In my custom board, Two inputs are received from two external battery power supplies, 28V each. I need to implement Oring circuit, where these 2 battery power supplies are given to an ORing circuit (LM74720-Q1 U1 and U2) and ORed output  VOUT is given to my on-board components.

Now, I'm facing issue where VBAT_1 goes low and VBAT_2 goes high, then EN pin of U1 goes low, thus PD pin of U1 pull down Q2 will be turned OFF, so Vout path will be OFF. Vout will be 0 volts. ORing function is not happening.

What changes can I do in the attached circuit, to get output voltage as expected as shown in above image?

  • 0
    TI__Genius 12755 points

    Hi Sanath,

    You are trying to achieve the design as shown.

    You can either OR EN pins also using a small signal diode such that controllers are always ON. Or you will have to power EN externally.

    Although these abs-max violations has to be taken care of.

    Regards,

    Shiven Dhir