I am using these PCA9685 servo driver boards to drive LEDs on several model railroad signals. I have them hooked directly to the PWM pins and the grounds as shown below. I have the servo value set at 4096 for their max brightness.
I have lost two PWM pins on the board that seem to have failed. I swapped to other pins to keep the LEDs working for now.
My question is am I damaging or stressing something with his operation? Should I add a resistor? It was my understanding that this board limits the current to a safe level so no resistors are needed.