This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM3643: VIN voltage level

Part Number: LM3643

Hi,

The customer plans to drive two LED (one @ LED1 pin and one @ LED2 pin) with LED spec as below.  Is there any concern here?  And is it ok to use 3.3V as input power to IN pin?  Thanks!

AntonySFH 4770SR7S_20190730.pdf

  • Hi Antony,

        The recommended operating range of Vin is 2.5~5.5V.  Hence, the 3.3V Vin is OK.

        The total output current(the sum of two channel) is about 1.5A in flash mode. And the LM3643 has 16 timeout levels ranging from 10 ms to 400 ms, which means the flash mode will not last more than 400ms. In Torch mode, the LED current sources (LED1/2) provide 128 target current levels from 0.977 mA to 179 mA(No time limit).

        So can you provide more details about your application?  For example, the nominal current of LED(corresponding to each channel in torch mode)? the flash current of LED? the last time of flash current?

  • Hi Antony,

        Do you have any more questions?

  • HI Charles,

    Currently no.  I'll make a new post if there's further question.  THanks for your support.

    Antony