TPS40210-Q1: Current Sense Filter

Zhang Yuxi

Part Number: TPS40210-Q1

In TPS40210-Q1 datasheet 7.3.4 : Current Sense Filtering, the suggested time constant is then: R × C = 0.1×Ton，Why the coefficient is 0.1? I hope get some theoretical explanation.

As the same the TI snubber design recommend : Fsnubber ≈ 0.1 Fring, here is the same coefficient 0.1. Is a same theoretical explanation between two formula?

over 5 years ago

0 Garrett Roecker over 5 years ago

TI__Mastermind 21720 points

Hi Zhang,

The value is a suggestion to set the current sense filter time constant. This allows for the current sense filter to have accurate current sense information while reducing the impact of the leading edge spike. These values can be modified based on the performance of the PCB.

Thanks,

Garrett

0 Zhang Yuxi over 5 years ago in reply to Garrett Roecker

Prodigy 70 points

Garrett,
Is there some theoretical explanation for the time constant 0.1?

0 EricLee over 5 years ago in reply to Zhang Yuxi

TI__Mastermind 46081 points

Hi,
The responsible engineer is out now. We will reply by 4/10.
Regards,
EL

0 Garrett Roecker over 5 years ago in reply to Zhang Yuxi

TI__Mastermind 21720 points

Zhang,

The value is based on experience is a guide line to find a starting point for the current sense resistor filter and snubber. Once the board is built the component values should be tuned in to help improve the performance of the circuit.

-Garrett

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TPS40210-Q1: Current Sense Filter