Version 2

    Inrush Current Limiters In Switching Power Supplies

     

    The problem of current surges in switch-mode power supplies is caused by the large filter capacitors used to smooth the ripple in the rectified 60 Hz current prior to being chopped at a high frequency.

     

    In the circuit above the maximum current at turn-on is the peak line voltage divided by the value of R; for 120 V, it is approximately 120 x √2/RI. Ideally, during turn-on RI should be very large, and after the supply is operating, should be reduced to zero. The NTC thermistor is ideally suited for this application. It limits surge current by functioning as a power resistor which drops from a high cold resistance to a low hot resistance when heated by the current flowing through it.

     

    GE SENSING / THERMOMETRICS - CL-11 - NTC THERMISTORGE SENSING / THERMOMETRICS - CL-11 - NTC THERMISTOR

    GE SENSING / THERMOMETRICS - CL-21 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-21 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-30 - THERMISTOR, SERIES CLGE SENSING / THERMOMETRICS - CL-30 - THERMISTOR, SERIES CL

    GE SENSING / THERMOMETRICS - CL-40 - THERMISTOR, SERIES CLGE SENSING / THERMOMETRICS - CL-40 - THERMISTOR, SERIES CL

    GE SENSING / THERMOMETRICS - CL-50 - ThermistorGE SENSING / THERMOMETRICS - CL-50 - Thermistor

    GE SENSING / THERMOMETRICS - CL-60 - THERMISTOR, SERIES CLGE SENSING / THERMOMETRICS - CL-60 - THERMISTOR, SERIES CL

    GE SENSING / THERMOMETRICS - CL-70 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-70 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-80 - THERMISTOR, SERIES CLGE SENSING / THERMOMETRICS - CL-80 - THERMISTOR, SERIES CL

    GE SENSING / THERMOMETRICS - CL-90 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-90 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-101 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-101 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-110 - THERMISTOR, SERIES CLGE SENSING / THERMOMETRICS - CL-110 - THERMISTOR, SERIES CL

    GE SENSING / THERMOMETRICS - CL-120 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-120 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-130 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-130 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-140 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-140 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-150 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-150 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-160 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-160 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-170 - THERMISTOR, SERIES CLGE SENSING / THERMOMETRICS - CL-170 - THERMISTOR, SERIES CL

    GE SENSING / THERMOMETRICS - CL-180 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-180 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-190 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-190 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-200 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-200 - NTC Thermistor

    GE SENSING / THERMOMETRICS - CL-210 - NTC ThermistorGE SENSING / THERMOMETRICS - CL-210 - NTC Thermistor