I can't understand this circuit board

AI Thread Summary
The discussion highlights the difficulty in understanding the circuit board due to the lack of a circuit diagram, with members noting that it's just a collection of components. There is speculation about the function of the board, with suggestions that it may involve battery management and LED control, but its purpose remains unclear. The PR 9490 component is identified as likely being an infrared detector, raising questions about its potential use in applications like motion sensing or fire alarms. The presence of a USB connector adds to the confusion regarding the board's functionality. Overall, without more detailed information or markings, it's challenging to determine the exact purpose of the circuit board.
Shauryafrom2006
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TL;DR Summary
I am unable to understand this circuit, help would be appreciated.
EC (4).jpg
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Since you have posted no circuit diagram, just a pic of some components, no one here is going to be able to figure it out either. It's a bunch of components, not a circuit, as far as we can see.
 
Some kind of cheap battery management and some kind of (likely cheap) LED control.
Can't even see the chip markings.
What's written on U1?
 
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Shauryafrom2006 said:
I am unable to understand this circuit, help would be appreciated.
What does it do, is it a motion sensing light, or a fire alarm ?
Why does it have a USB connector ?

The PR 9490 component in the middle of the PCB looks like an infrared detector.
Does it have a multi-facetted lens in the outer case that is not shown ?
 
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