LM5045: LM5045 EVM Overshoot Issue

James Su

Intellectual 280 points

Part Number: LM5045

My CTMR test LM5045 EVM dig out Vout Overshoot Issue, We need to know what's happen,

and how to explanation and solve this Issue, thanks !

over 7 years ago

0 Brian Johnson96 over 7 years ago

TI__Expert 3200 points

James,

An AE should be helping / contacting you soon on this E2E question.

0 Oliver Pan91 over 7 years ago

TI__Intellectual 2230 points

Hi James,

Have you modified anything on the EVM? We never saw such issue on the EVM, would you let me know how did you reproduce this issue.

Thanks

Oliver

0 James Su over 7 years ago in reply to Oliver Pan91

Intellectual 280 points

Hi Oliver,

No any modify, maybe you can try power on - off - on ... can more easy to dig out,

and I will order new LM5045 EVM to check again, thanks !

B/R James

0 James Su over 7 years ago

Intellectual 280 points

Hi Oliver,

Test new LM5045 EVM today,

The status is the same, pls noted.

0 Wangxin Huang over 7 years ago in reply to James Su

TI__Intellectual 1550 points

Hey James,

Can you provide SSSR cap, SS cap, Q6, Q8 and SR PWMs, voltage across R30 and Vo waveforms?

Regards,
Wangxin

0 James Su over 7 years ago in reply to Wangxin Huang

Intellectual 280 points

Hi Wangxin,

Customers take LM5045 standard EVM test found the problem (

), do not have the customer to do the board problem, the customer can't understand why we should continue to capture the waveform, TI should be able to obtain LM5045 EVM and measured problems, Thanks!

0 Oliver Pan91 over 7 years ago in reply to James Su

TI__Intellectual 2230 points

Hi James,

Sorry for the delay, I believe this issue was caused by the secondary reference not fully discharged during the short power-off time, it is important to keep secondary reference slowly rise from 0V to its final value during start-up, please increase the off time or add the dummy load on the SBias the accelerate the discharging and try again, thanks.

Thanks
Oliver

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

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LM5045: LM5045 EVM Overshoot Issue