Voltage Divider Calculator
Calculate output voltage, or any resistor value in a voltage divider circuit.
Calculate Voltage Divider Values
Common Voltage Divider Scenarios
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Understanding Voltage Dividers
A voltage divider is a simple passive linear circuit that produces an output voltage (Vout) that is a fraction of its input voltage (Vin). It consists of two series resistors (R1 and R2) connected across a voltage source.
Formulas
Resistor 1 (R1): R1 = R2 × ((Vin / Vout) - 1)
Resistor 2 (R2): R2 = R1 × (Vout / (Vin - Vout))
Where:
• Vin = Input Voltage
• Vout = Output Voltage
• R1 = Resistor connected to Vin
• R2 = Resistor connected to ground
Key Concepts
- Voltage Division: The process of reducing a voltage to a lower level using resistors.
- Resistor (R): An electrical component that opposes the flow of electric current.
- Input Voltage (Vin): The total voltage applied across the voltage divider circuit.
- Output Voltage (Vout): The voltage measured across the second resistor (R2) in the series.
Typical Resistor Values and Applications
| Application | Vin (V) | R1 (Ω) | R2 (Ω) | Vout (V) |
|---|---|---|---|---|
| LED Brightness Control | 5 | 1000 | 220 | 0.9 |
| Sensor Interfacing | 3.3 | 4700 | 10000 | 2.3 |
| Battery Voltage Monitoring | 12 | 10000 | 2200 | 2.16 |
| Audio Attenuator | 1 | 10000 | 1000 | 0.09 |
Frequently Asked Questions
What is the purpose of a voltage divider?
A voltage divider is used to scale down a voltage to a desired lower level. This is useful for various applications, such as providing a reference voltage, biasing transistors, or interfacing sensors with microcontrollers that operate at lower voltage levels.
Can a voltage divider be used to step up voltage?
No, a passive voltage divider can only step down voltage. It cannot increase the voltage. To step up voltage, you would need an active circuit like a boost converter.