LP3943: LP3943 led resistance selection

Aaron Chen (FAE)

Intellectual 1310 points

Part Number: LP3943

Hi Experts,

I am writing to know how to select these resistance (the red mark on the below picture).

Is there any consideration in the selection of resistance?

Thank you for the help.

over 3 years ago

+1 Aaron Bing over 3 years ago

TI__Expert 4160 points

Hi Aaron,

This document Pullup_Resistor_Calc introduces the basic equations to calculate the range of pull-up resistors from Page #2~4. In addition, the resistor values also depends on the forward voltage of LEDs chosen in the circuit. It can be roughly estimated by (5V - Vf) / 0~25mA.

Best Regards,

Aaron Bing

Power management

Power management forum

LP3943: LP3943 led resistance selection