LM5155: Replacement for opto coupler while using LM5155

ARCHIN N BABU

Part Number: LM5155

Tool/software:

Hi,

I am using LM5155 driver for isolated flyback transformer. In reference designs optocoupler is recommended for isolated feedback. But we have a requirement of system lifetime 15years. As photocoupler has less lifetime can you suggest a replacement for this.

Regards

ARCHIN N BABU

4 months ago

0 Moritz 4 months ago

TI__Mastermind 20835 points

Hi ARCHIN N BABU,

Thanks for reaching out.

There are opto-emulators like this device: https://www.ti.com/product/ISOM8111-Q1 It is available in an automotive and non-automotive version.

Best regards

Moritz

0 ARCHIN N BABU 4 months ago in reply to Moritz

Prodigy 130 points

Hi Moritz,

Thank you for your reply. We are looking for photo emulator with more than 6kV isolation. Can you suggest a part?

Regards

ARCHIN N BABU

+1 Moritz 4 months ago in reply to ARCHIN N BABU

TI__Mastermind 20835 points

Hi Archin n babu,

Please check all available opto emulators here : https://www.ti.com/product-category/isolation/opto-emulators/products.html

The max. isolation RMS volte is 5kV. Transients can go up to 7kV.

For more detailed information, please reach oput to the responsible team by oening a new E2E thread.

Best regards

Moritz

0 ARCHIN N BABU 3 months ago in reply to Moritz

Prodigy 130 points

Hi Moritz,

Thanks for reply.

For more lifetime I have selected above opto-emulator instead of opto-coupler. But I have observed photo emulator have larger response time. Will this cause any issue/delay in voltage regulation of flyback transformer used as gate supply to drive SIC modules (Totem pole topology)? Kindly confirm.

Regards

ARCHIN N BABU

0 Moritz 3 months ago in reply to ARCHIN N BABU

TI__Mastermind 20835 points

Hi ARCHIN N BABU,

ARCHIN N BABU said:
But I have observed photo emulator have larger response time.

How did you see a larger response time? Can you share your schematic and the measurements that show a larger response time?

Best regards

Moritz

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LM5155: Replacement for opto coupler while using LM5155