I'm using a Hobby King remote and 2.4ghz receiver to control an animatronic head. I'd like to enhance things a bit by putting a 5V SMD LED (ws2812b type) in each eye. Each channel of the receiver has 3 pins: ground, Vin and PWM. I get plenty of power to light the LED, but I'd like to use the PWM info (ideally without a microcontroller) to determine how bright the LED is. Depending on the position of the transmitter's potentiometer, the output voltage on the PWM is between .13 and .36.
Simply put, when the servo for the eyelids are in a closed position, I'd like the LEDs to be off or super dim, but when they are open, I want them to brighten up, all menacing like. Is there a simple circuit to facilitate this, maybe using a transistor or 555 timer? Or am I gonna need to use a 'duino to read in the PWM and pass it back out to light them up.