This tool provides the Analog-to-Digital Converter resolution and the digital value for an analog signal input to a 12-bit ADC.
Enter:
- Input Voltage Vin
- Reference Voltage Vref
- Number of bits
Formula for 12-bit ADC
The analog resolution or the smallest value that can be measured by the ADC is given by the formula:
(Vref)/212
where
- Vref is the reference voltage
The digital output from an ADC is given by the following formula for a 12-bit ADC.
Digital output = 212 * (Vin)/(Vref)
where
- Vin is the analog input
- Vref is the analog reference
Example Calculation for 12-bit ADC
For example, if an 12-bit ADC has a reference voltage (Vref) of 5V, the smallest change it can detect (quantum) is Vref / 212 = 5V / 4096 ≈ 1.22 mV. This means each step of the digital output corresponds to a change of about 1.22 mV in the input signal.
Analog input voltage of 1 Volt gives a digital output level of 1100110011.
Background
What is a 12-bit ADC?
An 12-bit Analog-to-Digital Converter (ADC) is a device that converts analog signals into digital signals. The “12-bit” part refers to the resolution of the ADC, meaning it can produce 212 = 4096 discrete values.
A 12-bit ADC is commonly used in applications where moderate resolution is sufficient and where a balance between cost, power consumption, and precision is needed. Examples include:
- Audio signal processing
- Industrial automation
- Medical instrumentation
- Consumer electronics
Advantages and Limitations
Advantages:
- Provides a good balance between resolution and conversion speed.
- Suitable for a wide range of applications.
Limitations:
- Higher resolutions (e.g., 16-bit or 24-bit) may be needed for applications requiring very high precision.
- Limited by noise and other analog signal integrity issues, which can affect accuracy.