Texas Instruments Evaluation Board for the LM5015 LM5015ISOEVAL/NOPB LM5015ISOEVAL/NOPB 데이터 시트
제품 코드
LM5015ISOEVAL/NOPB
Board Connections/Start-up
Figure 1. Evaluation Board Layout
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Board Connections/Start-up
shows the PC board layout. The input connections are made to connectors J1 (high potential)
and J2 (input return). The load is connected between connectors J3 (5V) and J4 (5V return). Ensure the
wires are adequately sized for the intended load current.
wires are adequately sized for the intended load current.
A DC power supply capable of at least 75V and 0.5A is recommended as the input power source for the
evaluation board. Use the output over-voltage and over-current limit features of the DC power supply to
protect the board against damage by errant connections.
evaluation board. Use the output over-voltage and over-current limit features of the DC power supply to
protect the board against damage by errant connections.
A resistive load is optimal, but an appropriate electronic load is acceptable. The maximum load current is
3A. Exceeding this current will cause the LM5015 to enter cycle-by-cycle peak current limit mode, and the
output voltage will fall below the regulated 5V. Current limit mode is triggered whenever the primary switch
current exceeds 1.2A (nominal).
3A. Exceeding this current will cause the LM5015 to enter cycle-by-cycle peak current limit mode, and the
output voltage will fall below the regulated 5V. Current limit mode is triggered whenever the primary switch
current exceeds 1.2A (nominal).
During the first power up, the load should be kept reasonably low (<0.1A). Before start-up, a voltmeter
should be connected to the input terminals, and to the output terminals. The load current should be
monitored with an ammeter or a current probe. It is recommended that the input voltage be increased
gradually.
should be connected to the input terminals, and to the output terminals. The load current should be
monitored with an ammeter or a current probe. It is recommended that the input voltage be increased
gradually.
Before the input voltage reach about 34V, which is the evaluation board’s Under Voltage Lock-Out (VULO)
threshold preset with R9 and R10, there should be no output voltage, and the input current should be
lower than 10 mA. Otherwise, remove power immediately and verify if the input polarity is reversed.
threshold preset with R9 and R10, there should be no output voltage, and the input current should be
lower than 10 mA. Otherwise, remove power immediately and verify if the input polarity is reversed.
When the input voltage is increased to 36V, the output voltage should be established at 5V nominal. If that
indicates correctly, increase the input voltage gradually to 72V maximum and the output voltage should be
regulated at 5V ±1.5% over the entire input voltage range from 36V to 72V. Otherwise, remove power and
check if the connection is correct.
indicates correctly, increase the input voltage gradually to 72V maximum and the output voltage should be
regulated at 5V ±1.5% over the entire input voltage range from 36V to 72V. Otherwise, remove power and
check if the connection is correct.
Once the proper setup has been established, full load can be applied. A final check of efficiency is
suggested to confirm that the unit is operating properly. Efficiency significantly lower than 80% at full load
indicates a problem.
suggested to confirm that the unit is operating properly. Efficiency significantly lower than 80% at full load
indicates a problem.
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AN-1724 LM5015 Isolated Two-Switch DC-DC Regulator Evaluation Board
SNVA291A – October 2007 – Revised April 2013
Copyright © 2007–2013, Texas Instruments Incorporated