820-02020 No backlight 0,8v on BKLT_EN_R

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  • hassie2001@gmail.com
    Member
    • Aug 2020
    • 12
    • Neteherlands
    #21
    Re: 820-02020 No backlight 0,8v on BKLT_EN_R

    Back at it again! Was on a holiday. Got my small LCD cable but still no luck. Now im thinking this was the problem all along... But while I was looking somewhere else I destroyed something!

    Originally posted by hassie2001@gmail.com
    The enable signal (BL_PWR_EN) comes directly from u8100, does that mean that u8100 is failing? It produces 0.8v but not enough to logic high (1.2v-1.8v)?
    I noticed that RP842 pin 1 has a diode mode reading 0.019 and 0v which was 0.187 and 0.8v. But should have been 0.375.

    When I remove RP842 I can see diode mode reading of pin 2 is 0.575 and pin 1 is 0.019! im really out of ideas now!

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