TPS92641 uto-zero calibration

T Kishi

Genius 4425 points

Other Parts Discussed in Thread: TPS92640

Please answer to our questions.

1.Or "auto-zero calibration" is performed at any timing?

　Such as, for example, are synchronized to the SW frequency, please tell me if there is.

2.To start the "auto-zero calibration", it is necessary to satisfy " Roff<(100xVout)xRf".

　⇒Is no problem in recognition?Also, there are other conditions?

Regard

T Kishi

over 8 years ago

0 Clinton Jensen over 8 years ago

TI__Mastermind 25500 points

LM3419_true0_analysis_April12.docxI am not sure I understand the question. All the zero calibration is doing is introducing an offset so that you can dim all of the way to zero current through the LEDs. The TPS92640/41 used to be called the LM3418/19. See the attached file explaining how the zero calibration works.

0 T Kishi over 8 years ago in reply to Clinton Jensen

Genius 4425 points

Hi Clinton
Thank you for reply.

The question background,My customer has evaluat in the EVM.
However, offset voltage of VADJ have received a question because there is about 2.5mV.
Therefore, the error at the time of light load is has become very large.
First, let me use this article.

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TPS92641 uto-zero calibration