(K/W) time (s) IMS PCB Simulated FR4 4-layer Simulated IMS PCB Measured FR4 4-layer Measured 10 1 10 -2 10 10 10 1 10 10 10 2 3 10 4 -1 -2 -3 Z th(j-amb) aaa-037922 10 10 -1 2 IMS FR4 1-layer FR4 4-layer FR4 2-layer FR4 2-layer Simulated FR4 2-layer Measured FR4 1-layer Simulated FR4 1-layer Measured