Circuitry in self-blinking LEDs ?

[Externet]

Hello.
What is likely the microcircuitry inside the self-blinking monochrome LEDs ? Also looking for 0.3 to 0.5 Hz LEDs; do you know if those exist in any single color ?

 

[Audioguru]

Red or blue on and off LEDs and red-blue-red-blue etc LEDs are available, probably sold by ebay and AliExpress.

 

[BradtheRad]

Blinking circuit is internal custom IC (according to my Radio Shack Semiconductor guide 1980). If we were to build one from scratch, its timing capacitor might be an electrolytic as large as the led itself!
Therefore I imagine the store-bought led contains a tiny high-frequency pulse generator feeding a multi-stage frequency divider.

The flasher led is handy for providing an all-purpose flashing signal useful to turn any circuit On-and-Off.

 

[Externet]

Thanks.
That is the part am curious about. For timing, the typical is the duration of a capacitor charge/discharge. It just does not fit in a square mm. Divider circuits... yes, can be but still need an oscillator...

Wonder if there is a light sensor that shuts the LED driver off when light gets emitted; but would still need a capacitor to tailor time...

 

[Audioguru]

All modern opamps have a tiny capacitor in the IC for frequency compensation. The timer in a flashing LED could have the same tiny capacitor in an oscillator circuit with a frequency divider circuit.

 

[ZASto]

WOW, oscilators and who knows what
Basic astable multivibrator. Simple as that, easy to make on silicone wafer.

 

[Audioguru]

WOW, oscilators and who knows what
Basic astable multivibrator. Simple as that, easy to make on silicone wafer.

The capacitors on a silicon (not silicone "rubber") wafer must be tiny with a very low value which makes the oscillator operate at a very high frequency, needing a digital divider to lower the frequency to a flashing speed.