SLUUCN1C June 2022 – December 2022 UCC28C50 , UCC28C50-Q1 , UCC28C51 , UCC28C51-Q1 , UCC28C52 , UCC28C52-Q1 , UCC28C53 , UCC28C53-Q1 , UCC28C54 , UCC28C54-Q1 , UCC28C55 , UCC28C55-Q1 , UCC28C56H , UCC28C56H-Q1 , UCC28C56L , UCC28C56L-Q1 , UCC28C57H , UCC28C57H-Q1 , UCC28C57L , UCC28C57L-Q1 , UCC28C58 , UCC28C58-Q1 , UCC28C59 , UCC28C59-Q1
As shown in figure 5-35, the UCC28C56H EVM was placed in a protective enclosure to isolate the high-voltage (VIN > 50V) from test personnel. The enclosure did not provide any forced air movement (i.e. there are no fans). The following thermal results should be considered worst-case due to the dead-air environment. For each load condition, the soak time was 30 – 45 minutes.
The hottest component on the EVM is the transformer. The transformer temperature was taken two ways: (1) by a thermocouple taped directly to the top of the windings (see figure 5-36), and (2) using a thermal camera and black electrical tape placed directly over the thermocouple/windings (see figure 5-37). The two methods provided results within 2 °C of each other. Temperature of the output rectifier diode and switching MOSFET were taken only with the thermal camera. The PCB temperature near the transformer was measured with a thermocouple.
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Transformer & PCB Temperatures:
Transformer TRISE = 53.9 °C - 30.6 °C = 23.3 °C |
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Transformer & PCB Temperatures:
Transformer TRISE = 86.5 °C - 37.6°C = 48.9 °C |
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