I am trying to build a boost converter to drive a powerful LED. The input will be 21 volts from 5S 18650 batteries to an adjustable 43V-54V (general voltage range) output with a 3A cap. I am looking at an integrated switch DC switching regulator as the center of the circuit. This one in particular because of its 10 amp current capability, its short parts list, as well as the wide input voltage range. Below is the schematic for a 5v-12v boost converter included in the Datasheet (I understand this is for a different chip however, from what I can tell they are functionally the same just with different maximum switch currents and this datasheet has all of the details). Now finally to my question. In the datasheet (page 7), it specifies that the pin (Vc) can be used for current limit adjustment. Specifically, Vc=0.9V is low output current and Vc=2V is high output current. The reference voltage is 1.244 volts at the FB pin with 0.8V at the VC pin. This indicates that I need some sort of potentiometer set up in the circuit to have an adjustable current supply. Would I do so by changing the resistance value of the resistor coming off of the Vc pin, or by changing resistor 2 of the voltage divider going into the FB pin to GND?
I understand that I will have to change some values because I am using a higher voltage.
Please ask if you need me to clarify anything.
I understand that I will have to change some values because I am using a higher voltage.
Please ask if you need me to clarify anything.