I want to use a step-down LED driver and configure it to deliver a constant current to some LEDs. This one looks nice:
I can control the brightness with a PWM signal into the CTRL pin. But how do I control the on/off of the LEDs?
Should I send a PWM signal with a 0 % duty cycle (is it possible?), or switch off the LED driver with an external transistor?
In the datasheet they seem to make the distinction between PWM frequency and switching frequency. Moreover they are talking about a soft-start which is 0.1 ms. Does it apply only when the LED driver is supplied with current, or each time the PWM signal reaches 0?