LM5119: Parallel LM5119 in redundant PSU

Eric Lai

Expert 4940 points

Part Number: LM5119
Other Parts Discussed in Thread: TPS40050, UCC39002

Hi Expert,

The customer would like to consider the LM5119 into their redundant PSU.

Condition:

PSU1 12V from LM5119 ( Interleaved Single Output)

PSU2 12V from LM5119 ( Interleaved Single Output)

Do we have the LM5119 reference design include the current sharing in for this applicant? And we want to know any concern had for parallel the PSUx with LM5119(s) now.

Thanks.

Best regards,

Eric Lai

Field Application Engineer

Texas Instruments Taiwan Limited

O: +886-2-2175-2582

M: +886-909-262-582

E-Mail:Eric.Lai@ti.com

over 5 years ago

0 Qian Chen over 5 years ago

TI__Mastermind 24075 points

Hi Eric,

Is PSU1 and PSU2 a 2phase or 4phase design?

LM5119 can be used for single output 2phase design. The reference design is availble on datasheet page 31.

Also, two LM5119 can be used for a interleaved 4phase design. The relevant information is on datasheet page 20.

Thanks

Qian

0 Eric Lai over 5 years ago in reply to Qian Chen

TI__Expert 4940 points

Hi Qian,

We are saying parallel the LM5119 for redundant applicant as below applicant report fig.2.
There are two PSU,and each of them has a single LM5119 ( Interleaved with Single Output) inside.Then system will parallel the 2 PSU.

Load-Sharing TPS40050 Modules Using the UCC39002 Load-Share Controller (slua311.pdf)
www.ti.com/.../slua311

For this applicant,will need to consider the current sharing.
Do we have the reference design or any concern might need to considered?

Thanks.

Best regards,

Eric Lai

Field Application Engineer

Texas Instruments Taiwan Limited

O: +886-2-2175-2582

M: +886-909-262-582

E-Mail:Eric.Lai@ti.com

0 Qian Chen over 5 years ago in reply to Eric Lai

TI__Mastermind 24075 points

Hi Eric,

When two LM5119 work together, one should be master and the other should be slave.
The master part use control loop to regulate Vout and provide COMP signal to slave part.
If master part does not work or is removed, the slave part is not able to work any longer.

We can not set both parts to master, because current sharing between two parts can not be achieved.
So two LM5119 can not be used for redundant design.

Thanks
Qian

0 Eric Lai over 5 years ago in reply to Qian Chen

TI__Expert 4940 points

Hi Qian,

Thanks.
Do you think whether we can use UCC39002 for this redundant applicant?

Best regards,
Eric Lai

Field Application Engineer
Texas Instruments Taiwan Limited
O: +886-2-2175-2582
M: +886-909-262-582
E-Mail:Eric.Lai@ti.com

0 Qian Chen over 5 years ago in reply to Eric Lai

TI__Mastermind 24075 points

Hi Eric,

I think UCC39002 can work with LM5119 parts for redundant appliation.

Thanks
Qian

Power management

Power management forum

LM5119: Parallel LM5119 in redundant PSU