Jännitejakajat

Jännitejakaja, or voltage divider in English, is a simple passive linear circuit that produces an output voltage (Vout) that is a fraction of its input voltage (Vin). It is typically constructed using two or more resistors in series. The most basic form consists of two resistors, R1 and R2, connected in series across a voltage source. The input voltage Vin is applied across the series combination of R1 and R2, and the output voltage Vout is taken across R2.

The principle behind the voltage divider is Ohm's Law. Since the resistors are in series, the same current flows through both R1 and R2. This current is determined by the total resistance of the series combination (R1 + R2) and the input voltage (Vin). The voltage drop across each resistor is then calculated by multiplying this current by the resistance of that individual resistor. Therefore, the output voltage Vout across R2 can be calculated using the formula: Vout = Vin * (R2 / (R1 + R2)).

Voltage dividers have numerous applications in electronics. They are commonly used to step down a higher voltage to a lower one for components that require a specific, lower voltage level. They can also be used to create reference voltages, adjust signal levels, and in sensor applications where the resistance of a sensor changes with a physical quantity, thereby altering the output voltage of the divider. However, it's important to note that a voltage divider's output voltage is load-dependent. If a significant current is drawn from the output, the effective resistance in the R2 position changes, altering the output voltage from its calculated value.