Hi.
I'm developing a DC/DC based on two balanced LM5116 controllers, with a 66-78V input and 48V 5A output. And I'm having difficulties setting accurate overcurrent threshold using the CS and CSG inputs on the controllers. Firstly, the overcurrent threshold where the controller resets is very dependent on the input voltage. Secondly, changing the Cramp capacitor value will greatly change the overcurrent threshold. With the setup I'm using now, a 5% tolerance in Cramp, leads to that the overcurrent threshold varies from 2A and 3A through the sense resistors.
My question is if it's at all possible to achieve an accurate overcurrent threshold using the overcurrent feature in the LM5116? Or do I have to have a current measuring opamp with a separate sense resistor or similar on the input voltage, and turn the LM5116s off using the UVLO pin?
Any help would be grateful!
BR,
Øystein Johnsen.
