What I'm doing here is using 2 PWM signals generated by 555 timers to control the warmth of the LEDs and the brightness. The top 555 is the brightness control and bottom one is the warmth. For the warmth, I run the same signal through an inverter so that when I change the duty cycle of the bottom 555 timer, one LED gets brighter and the other darker. For the brightness, I combine the top 555 with the bottom PWM signals using AND gates.
This circuit works, but the only problem is that when I finally combine the signals, the lowest brightness setting is not dim enough. Both of the 555s duty cycles range from 95% to 5%. On the other hand, the warmth control works perfectly fine. Could this be of the big difference between the timer frequencies? Or perhaps there are some design flaws in the circuit?
Also no, using an MCU is not an option. Thank you for your help.
EDIT: Forgot to add to the circuit, but I have added decoupling caps at both 555s to reduce noise.