Maximum isolation working voltage

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ergin
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Hello everyone,

I am looking for a gate-driver IC, which need to possess high insulation characteristics. I am trying to build a 3-phase bidirectional inverter (2 Level AFE) with a DC-Link voltage of 1200V. Where a RMS-voltage of 1200V appears across power modules (in my case are SiC-MOSFET power modules). Therefore there should be an Isolation between high- and low voltage sides accordingly. I've checked the Infineon's gate driver ICs  but the maximum isolation working voltage (in RMS) is not mentioned in most of the driver data sheets. "Reinforced insulation data according to VDE 0884-11" and "according to time dependent dielectric breakdown voltage TDDB test". There are some IC data sheets, in which this voltage of Viowm = 1000V is given, but it is not enough for my application voltage of 1200V. I've found a IC from texas instruments, and all isolation datas are given in data sheet. I've attached a screenshot of isolation part.  But the problem is this IC and many of Infineon ICs are not available. 

best regards

ergin

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Guru_Prasad
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250 replies posted 100 solutions authored 25 likes received

Hello @ergin 

Infineon has a maximum rating of 2300V class. Those are filtered on the product page .please click here.

I just want to know your product application and voltage class.

looks the link which was provided will help with your application.

Note: The relation for Viowm and Viorm is  given below

Viowm=Viorm/1.414

Note: Unfortunately, Infineon doesn't have Viowm>1k 

Thanks

Guru

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Guru_Prasad
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250 replies posted 100 solutions authored 25 likes received

Hello @ergin 

Thanks for posting your question in the Infineon community.

Please let me know what is your  Viowm?

Thanks

Guru 

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ergin
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ucc21750_isolation.png

Hello Guru,

Thanks for responding my question,

Viowm is maximum isolation working voltage defined in RMS, which is determined by AC Voltage (sine wave) time dependent dielectric breakdown (TDDB) test. This value is defined in insulation specifications according to VDE 0884-11. And VDE 0884-11 is active certification standard for evaluating the intrinsic insulation characteristics and high-voltage capabilities of magnetic and capacitive galvanic isolation products.

best regards 

ergin

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ergin
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Hello,

Viowm is in another words, the consistent voltage that the isolation barrier of product needs to withstand for the lifetime of the system.

best regards

ergin 

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Guru_Prasad
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250 replies posted 100 solutions authored 25 likes received

Hello @ergin 

Yes, I agreed with the explanation of   Viowm.

May I know what is the preferred voltage value for Viowm in your application?

Infineon have maximum rating of 2300V class . Those are filtered in the product page .please click here. 

let me know if you need any help

Thanks

Guru

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ergin
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Untitled.png

Here is the insulation characteristics part of the datasheet of IC "1ED3491MC12M".

Untitled.png

Can you please show me here the value Viowm? it is not defined. To define its value, it should first be tested. I already checked other similar IC with Viowm defined in its own datasheet, which have a maximium working voltage of 1000 Vrms. But I need an IC at least with Viowm of 1200 Vrms. 

best regards 

ergin

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ergin
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Untitled.png

here is a Half-bridge drive IC "2EDF7275F" with voltage class of 650 V. And Viowm (max. Isolation working voltage for reinforced isolator between high- and low-voltage side) is given to be 1000Vrms. 

best regards 

ergin

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Guru_Prasad
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250 replies posted 100 solutions authored 25 likes received

Hello @ergin 

Yes, correct 

Viowm=Viorm/1.41 is the relation 

Thanks

Guru

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ergin
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5 replies posted First reply posted 5 sign-ins

Hello @Guru_Prasad 

So can you help me with it? or i should seek another solution for it. 

best regards

ergin

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ergin
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5 replies posted First reply posted 5 sign-ins

because it is actually material characteristic, which used as Isolation barier. There may be an additional info sheet which describes insulation characteristics for some Infineon IC family.

best regards

ergin 

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Guru_Prasad
Moderator
Moderator
Moderator
250 replies posted 100 solutions authored 25 likes received

Hello @ergin 

Infineon has a maximum rating of 2300V class. Those are filtered on the product page .please click here.

I just want to know your product application and voltage class.

looks the link which was provided will help with your application.

Note: The relation for Viowm and Viorm is  given below

Viowm=Viorm/1.414

Note: Unfortunately, Infineon doesn't have Viowm>1k 

Thanks

Guru

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