I am using a DC1601B-C buck-boost converter in an automotive circuit to power some various electronics that I have added. It worked fine for a couple months, but under a less-than-normal load of 2.25A (when it should be able to output up to 20A) the input power pin caught fire.
In my circuit I also have a SLD8S17A TVS diode attached between the input power and ground to block the load dump. The diode was still functional after the fire so I don't believe the fire was caused by load dump.
In the DC1601B-C datasheet, the test instructions say not to "hot plug" the board. It also says to start power with the J1 jumper in the "OFF" position and switch it to the "ON" position after input power was applied. I had the board soldered into the circuit and left the jumper in the "ON" position, then applied power by turning a key switch with the load already attached.
I tried to research what hot plugging was and all I could find was hot plugging devices into a computer while the computer was still on, which I am not doing, so I am not sure what hot plug means in relation to a voltage converter.
My question is, was I "hot plugging" the converter by having it soldered into my circuit with the load attached before the power was turned on? And a follow up question is what else could have caused the input line to blow/what other protection circuitry am I missing?
As you can see in the photos below, the regulator caught fire only at the input power pin.
How can I prevent the DC1601 demo board from catching on fire?