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What's the maximum output current of STLD40D?

TIENHUA
Associate II

Hi Sir,

 

What's the max output current?

There only shows the min current 20mA of Io.

TIENHUA_0-1720405408225.png

Thank you.

@STLD40D

@Led

1 ACCEPTED SOLUTION

Accepted Solutions
Peter BENSCH
ST Employee

As with any boost regulator, the maximum output current depends on various parameters: output voltage = length of the LED chain, duty cycle, inductance, peak current, ripple current, etc. If you set the maximum peak current to 1A with Rset, you may be able to achieve a current of 35mA instead of 20mA, but this also requires a coil with a corresponding saturation current (min. 2A).

Please also take a look at AN2333, which deals with the dimensioning of the circuitry.

Does it answer your question?

Regards
/Peter

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

View solution in original post

2 REPLIES 2
Peter BENSCH
ST Employee

As with any boost regulator, the maximum output current depends on various parameters: output voltage = length of the LED chain, duty cycle, inductance, peak current, ripple current, etc. If you set the maximum peak current to 1A with Rset, you may be able to achieve a current of 35mA instead of 20mA, but this also requires a coil with a corresponding saturation current (min. 2A).

Please also take a look at AN2333, which deals with the dimensioning of the circuitry.

Does it answer your question?

Regards
/Peter

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

Hi Peter,

 

Thanks for your feedback.

Could you help share the equation of  ILIMIT and RSET, ILed and RLED?

I cannot find the equation in datasheet.

TIENHUA_0-1720506742919.png

 

TIENHUA_1-1720506838084.png