Hi,
I am trying to design a Power Board Supply with the LM5118 that will output 24V 2A that is then further connected to a 12V (OKI-78SR-12/1.0-W36-C) & 6V regulator (L7806CV-DG).
I have two problems:
1. When I start up the from an adjustable DC power supply and supply >10V, the LM5118 output drops below 5V. Even when the either of the regulators are not connected. However, when I dial the power supply back to 9.8V it resets and the Vout is the expected 24V. Is there a way to ensure that the output will 24V when it boots up with input voltages up to 24V?
2. When the lm5118 outputs 24V and it is connected to the 12V & 6V regulator are connected, the mosfet (Q1, KIA50N06B) that is connected to Vin will heat up very quickly. Is there a way to fix this? Does this have anything to do with the gate driver pin H0?
Thank you for your time.
Please note:
That I have removed R10 to ensure the EN pin has a high enough voltage supply.
Here is the schematic diagram.