Pumppujännitesovittimien

Pumppujännitesovittimet, known in English as charge pumps or voltage multipliers, are electronic circuits that produce a higher voltage than the input voltage by using capacitors as temporary energy storage elements. They do not rely on inductive components like transformers. Instead, they employ switching elements, often diodes or transistors, to transfer charge from one capacitor to another in a controlled sequence, effectively stacking voltages.

The operation of a basic charge pump involves charging a capacitor to the input voltage and then reconfiguring the circuit so that this stored voltage is added to the input voltage, resulting in a higher output. This process is typically driven by an oscillating signal, which synchronizes the charging and discharging of the capacitors. Multiple stages of this process can be cascaded to achieve significantly higher output voltages.

Charge pumps are advantageous due to their small size, low cost, and simplicity, especially when compared to inductive voltage converters for low-power applications. They are widely used for tasks such as generating higher gate drive voltages for MOSFETs, powering LCD displays, boosting voltage for analog circuits, and providing negative voltage rails. However, their efficiency can decrease significantly at higher output currents or voltage ratios, and they can introduce more noise than linear regulators. The output voltage regulation is typically not as precise as with other voltage regulation methods without additional feedback circuitry.