80 and 160 W. Triple output, low-noise, and feature packed — our most popular bench DC power supply. E36200 Series. 200 and 400 W. Single and dual output, autoranging provides more current at all voltages for power hungry devices. E36100 Series. 30 to 40 W. Single output, low-noise, designed for today's low power devices. CC - Constant Current mode: When the power supply is in constant current mode, it will limit the output to voltage that gives the setup current value through the load. OCP - OverCurrent Protection: When over current function is turned on, if the output current is higher than protection setup value, the output cuts off - ie. goes to 0V. Simple Current Limit Circuit: . 5V. GND. R2. +12V. Q1 2N3904. 1K Q2. 2N3904. R1. 14. GND. This circuit will limit the current through the load to about 50ma. As before when the input to the base resistor is 5V Q1 turns on and current flows through the load. When the input is low Q1 is off and no current flows through the load. September 19, 2008. Most AC-DC power supplies and DC-DC converters have internal current-limiting circuits to protect the power device, and to some degree its load. The majority of over-current-protections include an automatic recovery feature. In practice, the current limit feature typically starts operating when the output current exceeds it In your example, the current limit is set to turn on when the voltage on Rsens is enough to turn on Q2, or about 0.7 volts. When shorted, your system does not shut down but continues to deliver this current into your short. switch-mode-power-supply; dc-dc-converter; protection; or ask your own question. The Overflow Blog Can GenAI 10X Many power supplies employ constant current limiting protection; foldback goes one step further by linearly reducing the output current limit as output voltage decreases. However, it adds complexity to the power supply. If one has enough space, and is operating at low enough power levels, that having the supply draw the maximum current from its source transform and dissipate all the power as heat would not pose a problem, a transformer, a regulator, some caps, a handful of resistors and two LM317 regulators would suffice [without current limiting one would Often a power supply design team will browse potential thermistors from different suppliers and seek to balance thermistor inrush current characteristics against the impact on power supply efficiency. An example NTC thermistor suitable for inrush current limiting in AC-DC power supplies is the TDK B57464S109M. This thermistor has a nominal Tg0qgR.