I am new to the construction of DC/DC power supplies (still a university student) and have built basic supplies using simple linear voltage regulators. I have recently discovered the world of switching power supplies and their increased efficiency (in exchange for higher part counts). This is useful since I am building a project that can use 1.5A peak current at 5V, and I am using ~12V source. Linear Voltage Regulators are, from what I am reading at least, not a good selection for high current applications and heat becomes an issue.
I am wanting to use a TI TPS5420 step down switching voltage converter. I noticed the package (8-SOIC) is much smaller than many high current linear regulators, and that raises the question about heat and power dissapation. Linear regulators can require large heatsinks and larger packages at "higher currents" ( > 1A, but really counts on other factors like input voltage, output voltage, etc).
Can someone help me through how I would calculate the power dissipated through heat on this chip and if I should worry about the IC being too hot to touch? Even though the IC is more efficient than a large linear regulator, its also much smaller and doesn't have a thermal pad -- this makes me worry about how the heat is dissipated. Or am I just overthinking the issue?