Search results
Results from the WOW.Com Content Network
A switched-mode power supply will be affected if the brownout voltage is lower than the minimum input voltage of the power supply. As the input voltage falls, the current draw will increase to maintain the same output voltage and current, until such a point that the power supply malfunctions or its under-voltage protection kicks in and disables ...
Some devices may expose such attributes in multiple "pages", as for example one page managing each power supply rail (maybe 3.3V, 5V, 12V, −12V, and a programmable supply supporting 1.0–1.8V). The device may set warning and fault limits, where crossing a limit will alert the host and possibly trigger fault recovery.
A switched-mode power supply operating at the current limit with the output short-circuited does not have increased power dissipation in the power transistor(s), so foldback current limiting is an application feature only rather than one that also prevents a load fault from also destroying the power supply. The safety benefit of reducing the ...
In contrast, a linear power supply regulates the output voltage by continually dissipating power in the pass transistor. The switched-mode power supply's higher electrical efficiency is an important advantage. Switched-mode power supplies can also be substantially smaller and lighter than a linear supply because the transformer can be much smaller.
The resetting will often not take place even if the fault alone has been removed with the power still flowing as the operating current may be above the holding current of the PPTC. The device may not return to its original resistance value; it will most likely stabilize at a significantly higher resistance (up to 4 times initial value).
The values of the resistors are selected such that R 1 gives the highest load resistance, R 1 ||R 2 gives the nominal load resistance and either R 1 ||R 2 ||R 3 or R 2 ||R 3 gives the lowest load resistance. A voltmeter is then connected in parallel to the resistors and the measured values of voltage for each load state can be used to calculate ...
The output of the SEPIC is controlled by the duty cycle of the electronic switch (S1). A SEPIC is essentially a boost converter followed by an inverted buck-boost converter. While similar to a traditional buck-boost converter, it has a few advantages. It has a non-inverted output (the output has the same electrical polarity as the input).
A crowbar circuit is an electrical circuit used for preventing an overvoltage or surge condition of a power supply unit from damaging the circuits attached to the power supply. It operates by putting a short circuit or low resistance path across the voltage output (V o ), like dropping a crowbar across the output terminals of the power supply.