AIF25R48_03 Datasheet, PDF (14/29 Pages) Astec America, Inc – Isolated DC/DC Converter Module

AIF25R48 Series Technical Reference Note
Minimum Load Requirement
Fig.4 Trim Down Circuit and Formula
The minimum load of AIF25R48 series is 2.5A.
Output Over-Current and Short Protection
AIF25R48 series DC/DC converters feature foldback current limiting as part of their
Over-current Protection (OCP) circuits. When output current exceeds 110 to 140% of rated
current, such as during a short circuit condition, the module will work on intermittent mode,
also can tolerate short circuit conditions indefinitely. When the over-current condition is
removed, the converter will automatically restart.
A sound may occur from module when the output is shorted.
Output Over-Voltage Protection
The over-voltage protection has a separate feedback loop, which activates when the output
voltage exceeds 120% to 140% of the nominal output voltage. The module can restart by
turning on the power or turning on the CNT (CNT1 or CNT2/CNT3) signal again.
Over Temperature Protection
AIF25R48 series DC/DC converters will shut down when the temperature of the baseplate
reaches 101 to 120 , and the module will automatically restart if the temperature of the
baseplate is under 100 . The measurement point is indicated in below Fig 5. The module
must be mounted on a heatsink of 270mm 220mm 43mm when measuring OTP point.
DATE: May 28, 2003
MODEL : AIF25R48 SERIES
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