Just a little bored and felt like edumacating people...
Non-isolated boost converters, such as those used in a boost laser driver use an inductor to bump up the voltage. An inductor is a coil of wire --a device that resists change in current. If you have current flowing through an inductor and the current wants to change, the inductor attempts to prevent this the only way it can; by changing the voltage in the circuit.
See this image: http://www.ecnmag.com/uploadedImages/Ecn/Articles/ec7dsm100bFigure1.jpg
In a boost converter, a switch (typically a mosfet) will create a current through the inductor for a short time period. The mosfet then switches off and the current no longer flows. The inductor does not like this and will attempt to keep current flowing by boosting the voltage (turning its stored magnetic energy into electrical energy). However because the mosfet is open there is nowhere for the current to go: except through the diode.
The new electricity (at a higher voltage yet lower current) flows through this diode, typically a fast one such as a schottky, and out into a capacitor: a device that resists change in voltage. This capacitor will store the energy that the inductor discharges.
With the inductor almost fully discharged the mosfet switches on again and repeats the process (tens of thousands of times a second), and the voltage on the capacitor will reach a certain level determined by the % time (duty cycle) that the mosfet was on. A higher duty cycle will create a higher voltage, at the expense of current.
While all this is happening the laser diode uses the electricity stored in the capacitor. Typically boost converters are 80 to 95% efficient.
>gu'bai<
Non-isolated boost converters, such as those used in a boost laser driver use an inductor to bump up the voltage. An inductor is a coil of wire --a device that resists change in current. If you have current flowing through an inductor and the current wants to change, the inductor attempts to prevent this the only way it can; by changing the voltage in the circuit.
See this image: http://www.ecnmag.com/uploadedImages/Ecn/Articles/ec7dsm100bFigure1.jpg
In a boost converter, a switch (typically a mosfet) will create a current through the inductor for a short time period. The mosfet then switches off and the current no longer flows. The inductor does not like this and will attempt to keep current flowing by boosting the voltage (turning its stored magnetic energy into electrical energy). However because the mosfet is open there is nowhere for the current to go: except through the diode.
The new electricity (at a higher voltage yet lower current) flows through this diode, typically a fast one such as a schottky, and out into a capacitor: a device that resists change in voltage. This capacitor will store the energy that the inductor discharges.
With the inductor almost fully discharged the mosfet switches on again and repeats the process (tens of thousands of times a second), and the voltage on the capacitor will reach a certain level determined by the % time (duty cycle) that the mosfet was on. A higher duty cycle will create a higher voltage, at the expense of current.
While all this is happening the laser diode uses the electricity stored in the capacitor. Typically boost converters are 80 to 95% efficient.
>gu'bai<
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