8.2.2.14 Safe Operating Area

The safe operating area (SOA) of the device is shown in Figure 33 through Figure 36 for 3.3 V, 5 V, and 12 V outputs and varying amounts of forced air flow. The temperature derating curves represent the conditions at which the internal and external components are at or below the manufacturer’s maximum operating temperatures. Derating limits apply to devices soldered directly to a double-sided PCB with 2 oz. copper, similar to the EVM. Pay careful attention to the other components chosen for the design, especially the catch diode. In most of these test conditions, the thermal performance is limited by the catch diode. When operating at high duty cycles or at higher switching frequency the TPS54560B thermal performance can become the limiting factor.

Figure 33. 3.3-V Outputs

ƒSW = 800 kHz

Figure 35. 12-V Outputs

Figure 34. 5-V Outputs

ƒsw = 800 kHz

VIN = 36 V

VO = 12 V

Figure 36. Air Flow Conditions