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Switched-mode power supplies are used for DC-to-DC conversion as well. In heavy vehicles that use a nominal 24 V DC cranking supply, 12 V for accessories may be furnished through a DC/DC switch-mode supply. This has the advantage over tapping the battery at the 12 V position (using half the cells) that the entire 12 V load is evenly divided ...
A power semiconductor device is a semiconductor device used as a switch or rectifier in power electronics (for example in a switch-mode power supply). Such a device is also called a power device or, when used in an integrated circuit, a power IC.
In this mode, the operating principle is described by the plots in figure 4: [2] When the switch pictured above is closed (top of figure 2), the voltage across the inductor is =. The current through the inductor rises linearly (in approximation, so long as the voltage drop is almost constant).
A variant of this is to use two capacitors in series for the output smoothing on a bridge rectifier then place a switch between the midpoint of those capacitors and one of the AC input terminals. With the switch open, this circuit acts like a normal bridge rectifier. With the switch closed, it acts like a voltage doubling rectifier.
Modern regulated supplies mostly use a transformer, silicon diode bridge rectifier, reservoir capacitor and voltage regulator IC. There are variations on this theme, such as supplies with multiple voltage lines, variable regulators, power control lines, discrete circuits and so on. Switched mode regulator supplies also include an inductor.
A silicon controlled rectifier or semiconductor controlled rectifier is a four-layer solid-state current-controlling device. The name "silicon controlled rectifier" is General Electric 's trade name for a type of thyristor .
Whereas normal semiconductor diodes have a roughly fixed voltage drop of around 0.5 to 1 volts, active rectifiers behave as resistances, and can have arbitrarily low voltage drop. Historically, vibrator -driven switches or motor-driven commutators have also been used for mechanical rectifiers and synchronous rectification.
The input is on the left, the output with load (rectangle) is on the right. The switch is typically a MOSFET, IGBT, or BJT. Switching converters or switched-mode DC-to-DC converters store the input energy temporarily and then release that energy to the output at a different voltage, which may be higher or lower. The storage may be in either ...