I am interested in making an LED blink fast with a low duty cycle. To make the LED bright again (despite the low duty cycle), I thought I'd try to use some sort of charge pump to overdrive the LED. I'm hoping I can charge the capacitor while the LED is off, and place it in series with my voltage source when the LED is on.
Here's an example that doesn't work at all:
(ignore the LED model, ignore the capacitor rating)
The circuit correctly charges the capacitor when the LED is off. However the capacitor needs to be reversed during the "on" part. Is there some way to accomplish this with minimal additional transistors/diodes? One way I can guess is to have a sort-of H-bridge around the capacitor, but I'm hoping for something simpler.