Other Parts Discussed in Thread: CSD18503KCS,
This is in relation to a 12V boost to 24V 20A application for the LM5122MH-NOPB.
I have hot air reflow soldered 2 samples onto 2 circuit boards. On the first board the output voltage slowly rises and stays somewhere between 6V and 7V open circuit but I have seen it rise to 9V once. The output voltage increases as the input voltage increases. On the second board, the output voltage is 10V but also has a high idle current (0.1A) in open circuit. I have tried connecting RES to ground with no change, measured the UVLO pin at 1.5V, and the bench top power supply was 12V with a 500mA current limit set.
I've been so busy lately that this has been low priority, but it seems like these particular boards really need the voltage boosting to be more desirable for customers. I have attached the circuit diagram below and the top and bottom layers of the relevant PCB area. Please note the transistors are not the ones listed on the PCB layer images, they are all TI CSD18503KCS. The inductors are 3.3 milliohm each and the ones I've used on the prototype boards support up to 27A as they were currently easier to obtain.
I'm looking for advice on either the circuit design if there is any outstanding issues, or if it is down to the PCB layout or even some component choices.