MPM5452 output current is reduced with load current

Integrated Inductor Power Modules
1

Hi Team
We are using MPM5452 in one of out application, with all 4 channal , in current sharing mode . Our observation is we are increasing load current . Output volatge is decreasing (both load current and volatge Read from Active ELB ) . Please do let me know following

  1. If this behaviour is expected
  2. Does output voaltage varies depends on drrop voltage and which eventaully depends of load current. VOUTx = VREFx - VDROOP
    2)Can we change output voltage in run time
  3. How i can read load current and voltage ?
  4. Can you let us know how passive current balancing will work here , request you please share some applaication note .
2

Hello Singhab, Welcome to MPS forums!

Can you please clarify the part number? Are you’re referring to MPM54522?

Best,
Vignesh

3

Hi Vignesh

Sorry for mistake i ma referring to MPM54524.

4

  1. If the AVP feature is enabled, then the behavior you’re experiencing is expected.

    image
    image534×669 90.7 KB

  2. Yes, it depends on the load current as per the relation Vout = Vref - Vdroop.

    1. Whether you can change the output voltage during run time depends on whether you’re using the internal divider to set the output voltage or an external divider to set it.

      image
      image318×783 58.3 KB
      image
      image300×530 38.3 KB

  3. Can you kindly share your schematic and the bench setup you’re working with for further assistance with the measurements?

  4. With AVP enabled the current in each phase is inherently balanced.

    image

Can you also share the part suffix you’re using for MPM54524?

Best,
Vignesh

5

Hi Vingesh
Can you please share your e mail for sharing schematic .
Complete part no is MPM54524GCQ-0029Z
Regarding droop volatge ,while calculating (droop volatge what should be my Iout ie
Iout= load current or Iout =Load current/ 4 (ie no of o/p shared).

6

Hi Singhab,
I apologize for the delayed response, vignesh.iyer@monolithicpower.com is my email id.

for calculating droop voltage you’d use the total Load current.

Best,
Vignesh.