LM5157EVM-FLY: Some question regarding the output voltage and current.

Aaron Chen (FAE)

Intellectual 1310 points

Part Number: LM5157EVM-FLY

Hi Experts,

Regarding to the LM5157EVM-FLY, the three isolated outputs are in different current.

1. May I know how to set these output current?

2. From my perspective, three phases mean the three output will be the same.

Am I making sense? what is the definition of three phases? or It only means there are three outputs in this device.

3. From your perspective, what are these outputs for?

What application will need 10V/250mA & 20V/75mA & 20V/150mA?

BR, Thanks

Aaron Chen

over 2 years ago

0 Stefan Schauer over 2 years ago

TI__Mastermind 48961 points

Hi Aaron,

For a flyback you can have several independent output. The output voltage will then be cross regulated.

The load is just set by the design - identical to a flyback with a single output.

Just yesterday there has been an application report been published describing the calculation, perhaps this gives you the additional information you need.

https://www.ti.com/lit/an/snva940/snva940.pdf

Best regards,

Stefan

0 Aaron Chen (FAE) over 2 years ago in reply to Stefan Schauer

TI__Intellectual 1310 points

Hi Stefan,

I am curious about the schematic after these three output.

1. What will be connected after Vout 2,3,4? Do you have a function block or schematic of it? Does TI have the device that can be connected after this flyback?

2. Why does it need flyback structure on three phase inverter gate driver? For what kind of application that need the isolation power?

3. Why does the current of Vout 4 higher than others? Does this difference have any considerations?

4. From your perspective, main output 10V is for what applications or device?

BR,

Thanks

Aaron Chen

+1 Stefan Schauer over 2 years ago in reply to Aaron Chen (FAE)

TI__Mastermind 48961 points

Hi Aaron,

Sorry, I pasted the wrong link above, this is the right one:

https://www.ti.com/lit/an/snva994/snva994.pdf

(Target application is described in the introduction.)

Best regards,

Stefan

+1 Stefan Schauer over 2 years ago in reply to Stefan Schauer

TI__Mastermind 48961 points

Hi Aaron,

I have not seen an update on this thread for the last 27 days.

If the issue is solved it would be great to press the is solved button.

If there is still something open, just let me know with the new details.

Best regards,

Stefan

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LM5157EVM-FLY: Some question regarding the output voltage and current.