{Edited - Putting the LEDs closer to each other makes them easier to defuse}
Can anyone suggest a simple circuit I could use to PWM two strings of LED? To stay within my batteries current limit, I need the circuit to alternate the two strings. They can't be on at the same time. Bonus points if the circuit is dimmable i.e. one pulses, both dark, second pulses, both dark for adjustable periods.
I'm building a tapered, illuminated cylinder. I'm having trouble getting even brightness across the surface. The white LEDs I'm using show up as hot spots in the narrower sections. I don't have room for more diffusion material. Plus, I don't want to lose the light. Putting the LEDs closer makes diffusion easier. But I can't just jam in more LEDs due to my current limit. Hopefully, PWM on two strings will diffuse like one string.
The circuit has to be small and low power. I know I could do this with a small foot print Arduino, but I'd prefer to avoid that much complexity and cost.
Any other suggestions for solving this problem are welcome.