Texas Instruments Evaluation Board for the LM25118 Wide Vin Buck-Boost Controller LM25118EVAL/NOPB LM25118EVAL/NOPB Datenbogen
Produktcode
LM25118EVAL/NOPB
Efficiency
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Efficiency
Figure 1. Efficiency
illustrates the efficiency of the converter vs. input voltage and output current. These curves
highlight the high efficiency of the converter, especially considering the simplicity of design offered by a
non synchronous implementation. Note the discontinuity in the curves at approximately 17 V and 13 V
which represent mode transition boundaries. The lower efficiencies in the buck-boost region reflect
additional losses at higher input and inductor currents. The decrease in efficiency at higher input voltages
represents higher switching losses.
non synchronous implementation. Note the discontinuity in the curves at approximately 17 V and 13 V
which represent mode transition boundaries. The lower efficiencies in the buck-boost region reflect
additional losses at higher input and inductor currents. The decrease in efficiency at higher input voltages
represents higher switching losses.
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Air Flow
Prolonged operation without airflow at low input voltage and at at full power will cause the MOSFET’s and
Diodes to overheat. A fan with a minimum of 200 LFM should always be provided.
Diodes to overheat. A fan with a minimum of 200 LFM should always be provided.
illustrates the
temperature rise of various components with no airflow. The ambient was 25°C, and V
IN
was 8 V.
Figure 2. Temperature vs Load Current With No Airflow – 25°C Ambient
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SNVA614B – January 2012 – Revised January 2014
AN-2205 LM25118 Evaluation Board
Copyright © 2012–2014, Texas Instruments Incorporated