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In the words of David Byrne, "So... how do I work this?"

I'm trying to figure out how to bypass the dubious "motion sensor" (the black rectangle with the two circular openings) so the panel will just Go On When There's Power.

The power comes in via the brass-colored contacts just next to that, and goes out to the light via the three white wires (the two that are next to each other on the left are connected together on the light-panel terminal, despite the fact that one of them is labeled "LED+" and the other is labeled "LED-").

I could post a photo of the underside, but it's not very... illuminating.

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@woozle Ugh. Why did they have to mask the whole thing in white? You can't really see the traces...

I assume that IC1 is responsible for the motion sensing/time out stuff and that transistor next to the "real" LED- is what actually switches it on and off.

Is that bit of oddness on the left side of IC2 just a larger contact? If so IC2 is probably a voltage regulator.

If this were mine, what I would consider for ditching the motion sensing would be to ditch the whole board. Measure the voltage going to the LEDs when it's operational (and not actual polarity, since we already have reason not to trust the labels on the board), and then find a suitable replacement wall-wart.

Are there any markings on IC1? Maybe a datasheet can be found that would give some clues as to how this thing works and how a simple bypass might be constructed. (really hoping something like "a wire from this output pin to that resistor to enable the transistor", but it's hard to guess without being able to see any of the traces to build a schematic of the thing)

@woozle if you want detailed help we need better photos, both sides from a couple angles and with enough illumination contrast to see traces

@scanlime @woozle Based on just the components and their relative orientation, I'm going to say that's a 555 in the SOIC-8 package there on the right and that's an analog output IR prox sensor. Do you have a way of looking at the voltages on pin Q4 while the light is off and on? I'm guessing if you crowbar Q4 on or off, it'll keep the light on or off.

@jond @woozle really doubt that's a 555, i would assume app specific constant current flashlight driver chip

@jond @woozle if you try this be ready to disconnect quickly if the leds are brighter than usual 😳

@scanlime @jond

To be fair, the device does support dimming -- so there's probably some kind of oscillator in there.

If it's a 555, though, it's the smallest 555 I've ever seen... and also unlabeled. Is there a miniaturized surface-mount version of the 555?

@woozle @scanlime If it dims, my bet is off. You're right there has to be some current control there.

But, yes, you can get 555s in SOIC-8. Still the cheapest one-shots you can get.

@woozle @jond yes 555 comes in that package but i expect a higher level of integration with this few capacitors on the board

@scanlime I may do that tomorrow.

Amendments to a couple of things I said:

Actually, the two wires on the left are not tied together on the panel; they just looked that way from the easiest angle.

There are circuit traces faintly visible on the back side I don't know if I could photograph them as-is, but I could probably outline them with sharpie.

Additional info:

The input is 24vdc. The plug can be inserted upside down (not that there's any way to tell which way is "right side up") and it will work; the two outer terminals on the jack are +24v, and the middle one is ground/neutral.

I need extra limbs to hold the power plug in place while also measuring output voltages; I will see if I can use alligator clips instead, as my extra limbs have been on backorder.

The unit is designed to be chained with up to two additional panels (the top panel is the only one with a motion sensor). Unfortunately, plugging power directly into the other two does not switch them on, even though they use the same kind of plug -- from which I conclude that their power may (must?) have a different pinout.

@woozle i would assume a +-+ and -±- plug layouts for the two panels maybe. can you post the non-sensored panels too? would be interesting to see what their current regulation (if any) looks like

@scanlime Sure! This one was only slightly difficult to get apart because of the sensor poking up through the bezel; hopefully the others are easier.

@woozle you might be able to get photos showing the traces if you shine a light from a very low angle

@scanlime Got some photos taken, but still working on this; today has been a Day of Interruptions.

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