CCS/TMS320F28035: LLC issue

AndongSun

Part Number: TMS320F28035
Other Parts Discussed in Thread: UCD7138, TIDM-1001

Tool/software: Code Composer Studio

Hi expert:

There is a problem when my customer use TMS320F28035 for LLC control. Thanks for your support.

The output signal driven by synchronous rectifier will generate high level at the same time with a certain probability, resulting in the damage of the minor side short-circuit MOS.

As shown in the attached picture:

CH1,CH2:synchronous drive signal,

CH3 :output voltage,

CH4 LLC :resonant current

Best regards.

over 6 years ago

0 Chen Jiang ti over 6 years ago

TI__Genius 15935 points

Hi Andong,

Just want to let you know I am looking into it and will get back to you soon.

Regards,

Chen

0 Chen Jiang ti over 6 years ago

TI__Genius 15935 points

Hi Andong,

1. What is the topology? half bridge or full bridge LLC?

2. Is this based on our TMDSHVRESLLCKIT? Or it is based on the a customized board?

3. Is it based on TI reference design software? Or it is based on the customized code?

4. What do you mean by "minor side short-circuit MOS."?

Regards,

Chen

0 Chen Jiang ti over 6 years ago

TI__Genius 15935 points

Hi Andong,

Just want to follow up on the questions below. Have you already figured it out?

Regards,

Chen

0 AndongSun over 6 years ago in reply to Chen Jiang ti

Intellectual 600 points

Hi Chen,

1 TOP is half bridge LLC.

2 It is based on the customized board.

3 It is based on the TI reference softwareRefer to the code , and my customer have modified it.

4 Side SR MOS is short-circuiting.

Best regards

0 Chen Jiang ti over 6 years ago in reply to AndongSun

TI__Genius 15935 points

Hi,

We have the deadband implemented in TMDSHVRESLLCKIT_v1.0. Have the customer taken a look at it? Also we have TIDM-1001 using UCD7138 for SR.

We have the flexibility to add deadband after T1 T2 trip in type-4 PWM, but since the customer uses f2803x without type-4 PWM, they probably can not use that.

Regards,

Chen

C2000™︎ microcontrollers

C2000 microcontrollers forum

CCS/TMS320F28035: LLC issue