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Can someone identify IC "U1" in the below LED lamp PCB?
I've tried to google the identifiers but didn't find anything :-(

It's an 18 W lamp for 240 V AC, and according to the customer it's the second lamp within a few weeks that blew up (obviously fuse FS1 triggered after U1 experienced a "thermal anomaly").

What could be wrong? U1 simply overloaded? Wrong driver concept at all?

enter image description here enter image description here

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  • \$\begingroup\$ Sounds like you aren't the designer/manufacturer, but a reseller of a product. Can you just contact your supplier chain to ask for a root-cause determination? And is this just the one customer experiencing this difficulty? Or more than one? Am I misreading the situation? \$\endgroup\$ Jan 5 at 16:49
  • \$\begingroup\$ @periblepsis: Neither nor. I'm just the one who was asked to "have a look" by that customer (an old lady from the neighborhood). I recommended her to bring it back to the shop, but am anyway interested in the root cause of the failure. \$\endgroup\$
    – mic
    Jan 5 at 16:57
  • \$\begingroup\$ Understood and thanks. \$\endgroup\$ Jan 5 at 17:00

1 Answer 1

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It's hard to read the markings, but it seems to be a Kiwi Instruments KP18106WPA LED driver.

enter image description here

enter image description here

(Source: lcsc.com)

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    \$\begingroup\$ Nice. +1 Linear LED driver chip with integrated 800V bridge rectifier.. for 3 or 4 cents. \$\endgroup\$ Jan 5 at 19:57
  • \$\begingroup\$ Thanks! RCS is 10 Ohm. With V_RCS being 600mV typically, this means I = 60 mA, correct? This would be maximum current, but not outside the specification. Maybe the heat slug was not soldered? But the datasheet does also mention a thermal derating function... then I guess it's just poor silicon quality? \$\endgroup\$
    – mic
    Jan 5 at 21:20

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