Normally On Blinking Light Bulb From 555 Timer Circuit

[Circuit Dude]

Hi all,

I’m designing a circuit that will use a 555 timer to blink a light bulb. However, the bulb needs to be normally on and will blink only after the timer starts oscillating. The light bulb load will be 12VDC at ~5A.

Attached is a schematic of a circuit that I built using a N-channel enhancement mode MOSFET. The design works great with an LED. However, once I replace the LED with an incandescent light, the bulb stays dark. Does anybody have suggested changes to this circuit that will make a bulb like an automotive taillight blink?

Thanks for your help!

 

[colin55]

Where did you put the globe?

 

[Circuit Dude]

Where the LED is shown.

 

[colin55]

It must go in place of the resistor.

 

[Circuit Dude]

Thanks for the suggestion. The globe now blinks, but it is normally off. I need it to be normally on.

 

[colin55]

Try the first circuit. Obviously use the correct value components.

**broken link removed**

 

[Circuit Dude]

Will do...does the globe stay, as you previously suggested, on the drain side of the MOSFET?

 

[colin55]

The globe stays the same