Jännitealuked

Jännitealuked is a Finnish term that translates to "voltage divider" in English. It refers to an electrical circuit that produces an output voltage that is a fraction of its input voltage. This is achieved by connecting two or more resistors in series across a voltage source. The output voltage is then taken across one of the resistors.

The fundamental principle behind a voltage divider is Ohm's Law and the properties of series circuits. When resistors are connected in series, the total resistance is the sum of individual resistances. The same current flows through all resistors in a series circuit. According to Ohm's Law (V=IR), the voltage drop across each resistor is proportional to its resistance. Therefore, the voltage across a specific resistor in a series chain will be a fraction of the total voltage, determined by the ratio of that resistor's value to the total resistance.

A simple voltage divider consists of two resistors, R1 and R2, connected in series across an input voltage, Vin. The output voltage, Vout, is taken across R2. The formula for the output voltage is Vout = Vin * (R2 / (R1 + R2)). This circuit is widely used in electronics for various purposes, such as scaling down voltages for microcontrollers, setting reference voltages, and as part of more complex circuits like sensor interfaces. However, it's important to note that a basic voltage divider circuit has a high output impedance and is not suitable for powering loads that draw significant current, as the output voltage will drop under load.