DP83822I: how to calculate LED0/1 current.

Motoyasu Hattori

Part Number: DP83822I

Hi,

According to datasheet, A 1.96kΩ to 2.49kΩ resistor should be used as the parallel pull resistor. But we do not know how to calculate LED0/1 current or how to define Rcl registors. Please advise us. In other words, please let us know the MAX current to LED_0/1 pins.

We see the following comments, but it is too tough for everyone to calculate from IBIS. Also, we want to MAX current on output high or low, (Not during transition).
https://e2e.ti.com/support/interface/f/138/p/784329/2900641?tisearch=e2e-sitesearch&keymatch=DP83822%20AND%20LED%20AND%20current#2900641

Thanks and best regards,
M.HATTORI.

over 5 years ago

0 Cecilia Reyes over 5 years ago

TI__Genius 9920 points

Hi Motoyasu,

What is the reason you are interested in calculating the LED current on your device?

Thanks,

Cecilia

0 Motoyasu Hattori over 5 years ago in reply to Cecilia Reyes

TI__Genius 10955 points

Cecilia-san

LED brightness is determined by current. So we want how current of LED we want to flow.

Thanks and best regards,
M.HATTORI

0 Cecilia Reyes over 5 years ago in reply to Motoyasu Hattori

TI__Genius 9920 points

Hello,

You will need to add the R_CL resistor (Current limiting resistor) in series with the LED that will be in parallel with your strap resistor. There, you can measure the current through those resistors.

Thanks,

Cecilia

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DP83822I: how to calculate LED0/1 current.