I am having a faulty BOE-hm185wx1-400 panel, where the MLG voltage has dropped to 15 V instead of the usual 25.4 volts. After a bit of diagnosis, it appears that the DC-DC ic below is possibly faulty.


But I am unable make out the ic datasheet or find replacement based on what is written on it ER=1B 73H

Is this it's IC number? Just googling does not fetch anything... Please help me.

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    \$\begingroup\$ Only if they are forward biased would they read that <0.8V. Depends on what they are for in the circuit. In any case, diodes usually fail short. \$\endgroup\$
    – DKNguyen
    Aug 17, 2021 at 14:25
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    \$\begingroup\$ It's possible it's bad. It's also possible that your multimeter is not telling you the whole story if there are pulsed waveforms and filter caps involved. As @DKNguyen says, a short would be much more typical and you seem to have two anomalies. \$\endgroup\$ Aug 17, 2021 at 15:15
  • \$\begingroup\$ @DKNguyen @SpehroPefhany thanks for your help. Could you please help me a little bit more by helping me gather more information about the ic with ER=1B 73H written on it... So that I can possibly order a replacement... \$\endgroup\$ Aug 18, 2021 at 21:19
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    \$\begingroup\$ If I understand correctly, you've ruled out the diodes as a problem and are now looking to identify the DC/DC controller. Is that right? If so, please edit your question to reframe it as an ID question. Don't use "Update" or "Edit" or similar in the question text as we can already see the post history if we want to. \$\endgroup\$
    – Null
    Aug 19, 2021 at 12:32
  • \$\begingroup\$ @Null, you are correct. Ok I would make the changes to the question. Thank you for your guidance... :) \$\endgroup\$ Aug 19, 2021 at 15:38


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