Looking for explanation of how a transistor and resistor can make a flashing circuit with my local 5 meter lights.

Thread Starter

James90s

Joined Mar 3, 2021
31
Hello everyone.

I recently bought these 5 meter fairy lights from the local market. It operates with a slide switch, one transistor, and one resistor.
I was just wondering how the circuit can flash by only using a transistor and one resistor, and what is the name of a circuit like this.

Pictures below.

Thanks you.
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1630666808469.jpeg
 

Thread Starter

James90s

Joined Mar 3, 2021
31
It is connected to the slide switch. On what looks like a transistor it has the letter G. Could this help?
 

Danko

Joined Nov 22, 2017
1,823
It is: (see PDF).
ADDED:
I doubt that is a transistor, more likely a dedicated 'flasher' chip. What is the top LH solder blob (circled in red below) connected to?

Edit: like this one: https://www.ebay.co.uk/itm/301124079844, though different pinout.
Standby current is 1...2uA (see PDF-2), so they ON/OFF LED only (pin "OUT").
 

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zophas

Joined Jul 16, 2021
165
I think it's an indication of where electronics as a hobby is going. Everything is becoming smaller and smaller. Soon you will no longer put together circuits out of individual components. It will all be tiny little "modules" for any function you need. Kids will laugh at Grandad when he talks about a single transistor in it's own package. Lol.
 

Irving

Joined Jan 30, 2016
3,798
Note that the M34 chip I linked to in post #3 and the datasheet @Danko posted is NOT your chip. The pinout is different and the M34 chip is limited to 2 or 3 LED, not a 5m string.
 
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