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LP5018: VLED Usage

Part Number: LP5018


I am Youssef Elbadri, an Embedded Systems Engineer in the research and development department (I-D Tech) at Nile University, a leading institution in engineering in Egypt and the MENA region. I invite you to visit our website at

Our team is currently engaged in a project that involves the integration of a RGB LED driver, and we are considering the use of your solution (LP5018). In this regard, we are interested in obtaining information on the VLED pin utilization and the calculation of RIREF.

Specifically, we would like to get a clarify if there are any limits associated with the VLED pin or if it plays a role in determining LED current. We have observed that VLED does not appear to contribute to the selection of RIREF for a particular LED current.

Thank you in advance.

Best regards,
Youssef Elbadri

  • Hi Elbadri,

    Nice to hear you, I hope your project is running well!

    I noticed that you want to know the VLED pin's function, but our device LP5018 doesn't have this pin, so I guest you want to know the usage of VLED power supply.

    So, for your question, VLED will not affect the output current, the maximum output current is determined by RIREF.

    When you select a suitable VLED voltage, hear is something you need to concern:

    - Forward voltage of LED you selected(Vf)

    - Saturation voltage for your application condition:(Vsat)

    And when you select the VLED voltage, please make sure VLED>.Vf+Vsat

    Besides, the RIREF is used to determine the maximum output current for each channel, its value could be calculated by below formula:

    If you have more questions about TI's LED driver, please let me know.



    Ives Li