hello all, here is what i need to do. i need a circuit that when it gets a constant 12v input, will pulse 12v at maybe 100mA or less every 5 seconds roughly. doesn't need to be super accurate. i want to use this to cycle through the flash patterns on my emergency lights. i was thinking a 555 timer but I'm not exactly an electronic engineer. any help is appreciated

12v constant input
pulse 12v 100mA output every ~5 seconds

 

You're right, for a standard LED flasher you need a 555 circuit called an astable multivibrator. Take a look here, or Bill's blog.

 

You're right, for a standard LED flasher you need a 555 circuit called an astable multivibrator. Take a look here, or Bill's blog.

So which schematic would I use? I need a 12v output

 

555 flasher

 

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