SR PWM in 3300W 52 V LLC converter

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Rakesh_rp
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First solution authored 10 replies posted 10 questions asked

Hi,

 

I am testing   EVAL_3.3kw  52 LLC  Infineon code on a customized LLC board , we are following the Infineon reference design .

As per my understanding  to drive the synchronous rectifier at LLC secondary ,  microcontroller should generate two  PWM signals - > PWM_H  &  PWM_L.    The PWM_L   should be  a inverted signal of PWM_H.

But in the Infineon code , configuration of timer is done in such a way that  both  PWM_H  and PWM_L  are  same , no inversion is done . Both signals are generated from different timer slice.

I want to know  how synchronous rectification is achieved with this configuration ?

In the application note the software implementation is not mentioned. The code is documented partially, not enough to understand  the algorithm of the code.

Expecting a reply soon.

 

Regards,

RAKESH

 

 

 

 

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Vinay
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Hello @Rakesh_rp,

Good Day!

 

Sorry for the delayed response.

 

Synchronous rectification and signals inversion are not achieved via software. Here  synchronous rectification IC is used.

 

Please refer the data sheet of IR1161LPBF and the hardware schematic of the evaluation board (EVAL_3K3W_LLC_HB_CFD7).

 

Thank you!

 

Best Regards,
Vinay

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Vinay
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Hi @Rakesh_rp,

Good Day!

 

you are referring to Infineon code , "configuration of timer is done in such a way that  both  PWM_H  and PWM_L  are  same , no inversion is done . Both signals are generated from different timer slice".

 

 Could you please share the screenshot of the code you are referring?

 

Thank you!

 

Best Regards,
Vinay
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Hi,

Thanks for replying . The screenshot for configuring the two timer slice is shown below. These two are used to generate PWMs to drive the  Synchronous rectifier in LLC

Rakesh_rp_1-1654766949420.png

Rakesh_rp_2-1654767053396.png

 

 

 

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Vinay
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Hello @Rakesh_rp,

Good Day!

 

Sorry for the delayed response.

 

Synchronous rectification and signals inversion are not achieved via software. Here  synchronous rectification IC is used.

 

Please refer the data sheet of IR1161LPBF and the hardware schematic of the evaluation board (EVAL_3K3W_LLC_HB_CFD7).

 

Thank you!

 

Best Regards,
Vinay
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Vinay
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Hi Rakesh,

Good Day!

Sorry for the delay in responding. Please share the screenshot of the External event settings of PWM synch1 and PWM synch2

 

Thank you!

 

 

Best Regards,
Vinay
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