I'm planning on building my own 5W high power LED Lamp, and this is my current setup:
My power source is going to be 3 Li Ion Batteries in series, giving 14.8 volts for most of the time.
I then have the positive wire hooked directly to a Single Pole Single Throw switch, so if I have the circuit open there will be no current flowing, i.e. 0 power output from the battery.
These wires then lead to an adjustable buck boost converter with CC/CV, which I will set to a Constant Voltage of 12V and a Constant Current of 350mA as required by the LED
The output then goes through an adjustable PWM Dimmer with a potentiometerwhich then finally leads to the LED
This is my question - Is there anything wrong with having the PWM dimmer AFTER the Buck Boost converter?
I also want to know whether the entire circuit is going to be using 5W (exluding inefficiencies) all the time, regardless of whether I set the PWM dimmer to a duty cycle of 10%, 50%, or 100%?
Should I move the PWM dimmer BEFORE the Buck/Boost converter, so that I control the duty cycle before the power is sent on?