A similar study is then made to check if the customer has chosen the right bus converter; for the study there are 3 FPGAs each requiring 4.35A, requiring a total current draw of 13A. The TDK-Lambda IQL24021A120V-009-R appears suitable, has an input range of 20V-36V and is rated at 21A with an output voltage of 12V. Looking at the derating curves shown here, it can supply 13A in a 70°C ambient, and the system has derating of 50°C ambient. A heat sink could be used if further derating is needed.