I’m working on a 0-35V/18A voltage generator and I want to limit the current to 15A max independently of the output voltage. I use the MP5048 for current control and a dsPIC33EP512MU810 microcontroller for setpoint management.
Questions :
Is it possible to set a current limit of 15A on the MP5048 without using an MP5920?
If yes, how to configure the CLREF voltage to obtain this limitation?
What is the exact relationship between VCLREF and current limit, based on the internal shunt of the MP5048?
Can my dsPIC directly control current via CLREF?
I will answer your questions numerically in the order asked:
1.) You can set up the current limit by using the CLREF pin where the current threshold is based on a reference voltage. See page 16 of the MP5048 datasheet for more details. Here is a relevant snippet:
2.) This is how to configure the CLREF voltage to obtain this limitation, see more on page 17 of the datasheet.
3.) The exact relationship between VCLREF and current limit based off the internal shunt is a linear relationship. This is expressed in the equation above.
4.) Yes, your dsPIC33EP512MU810 should be able to output a DAC voltage or PWM (be sure to filter to DC) to set Vclref, allowing for real-time adjustment of the current limit from the MCU.
