Datasheet

Efficiency
2-4
2.2 Efficiency
The TPS54973EVM−017 efficiency peaks at a load current of about 1 A to 2 A
and then decreases as the load current increases towards full load. Figure 2−2
shows the efficiency of the TPS54973 at an ambient temperature of 25°C. The
efficiency is lower at higher ambient temperatures due to temperature
variation in the drain-to-source resistance of the MOSFETs. Efficiency is
slightly lower at 700 kHz than at lower switching frequencies due to the gate
and switching losses in the MOSFETs.
Figure 2−2. Measured Efficiency, TPS54973
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I
O
− Output Current − A
Efficiency − %
EFFICIENCY
vs
OUTPUT CURRENT
V
I
= 3.3 V