Hello,
I'm using TPS5450 on my PCB as the main power supply. Input voltage is 15 Volts
I have two issues with the design ;
1) As can be seen from the screen captures the signal waveform (on the PH pin) is not square. These are from two different boards. Same PCB, same parts.
2) The second issue I have is that sometimes the voltage won't go above 5 volts. I need to repeatedly plug / unplug until it starts running. (I have recently added a component that draws 300mA's and the non-start issue has disappeared, before the current draw was around 80mA )
I am a mechanical engineer, so my knowledge of electronics is limited. I have used parts suggested by the design tool, BUT have deviated from the suggested layout A LOT. As in putting the inductor on the other side of the PCB and using plenty of vias to make the connection (space limitations).
I am starting to design a new PCB (same overall schematic different layout) - I plan to follow the suggested layout this time but I am not sure the problem is really the layout or suggested parts.
Any input would greatly be appreciated, attached is the schematic I use.
Thanks
