Voltage divider calculator
Calculate the output voltage of a resistor divider circuit
Input Parameters
Calculation Results
Please enter parameters and click the calculate button.
Output voltage (Vout)
0 V
Equivalent resistance
0 Ω
Output current
0 mA
Formula: Vout = Vin × R2 / (R1 + R2)
R1: pull-up resistor, R2: pull-down resistor
Common partial voltage ratio reference
| R1:R2 ratio | Partial pressure ratio | Output voltage (12V input) |
|---|---|---|
| 1:1 | 50% | 6.00 V |
| 1:2 | 66.7% | 8.00 V |
| 1:3 | 75% | 9.00 V |
| 1:4 | 80% | 9.60 V |
| 2:3 | 60% | 7.20 V |
| 3:1 | 25% | 3.00 V |
Voltage divider circuit application scenarios
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Voltage signal sampling
The ADC front-end voltage divides the high voltage down to the ADC input range.
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Reference voltage generation
Provide stable reference voltage for comparators and operational amplifiers
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Level conversion
Convert 5V signals to low voltage levels such as 3.3V
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bias circuit
Provide static operating points for transistors and operational amplifiers
Precautions for use
- -The output impedance of the voltage divider circuit is equal to the parallel value of R1 and R2
- -When loaded, the actual output voltage will be lower than the theoretical value
- -For high precision applications it is recommended to use 1% or higher precision resistors
- -For high-power applications, consider the resistor power rating.