Question 1

What is a voltage divider and how does it work?

Accepted Answer

A voltage divider is a simple circuit that produces an output voltage that is a fraction of the input voltage. It works using two resistors in series, with the output taken from the connection between them. The output voltage is determined by the ratio of the resistors according to the formula: Vout = Vin × (R2 / (R1 + R2)).

Question 2

When should I use a voltage divider?

Accepted Answer

Voltage dividers are commonly used for: creating reference voltages for op-amps and comparators, biasing transistors, scaling input signals for ADCs, level shifting signals between different voltage domains, and creating simple voltage sources for low-current applications.

Question 3

What are the limitations of voltage dividers?

Accepted Answer

The main limitation is that the output voltage changes when a load is connected. The divider assumes no current draw from the output. For accurate voltage division under load, the impedance of the connected circuit should be at least 10x higher than the output impedance of the divider (R1||R2).

Question 4

How do I choose resistor values for my voltage divider?

Accepted Answer

Choose resistor values based on: the required output voltage ratio, acceptable power consumption (lower resistances = higher power), noise immunity (lower resistances = less susceptible to noise), and load current (the divider must supply enough current without significant voltage drop).

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