An Analog-to-Digital Converter (ADC) is an electronic device that converts continuous analog signals into discrete digital numbers. This process is essential in various applications, including audio processing, video processing, and data acquisition systems, where real-world signals (like sound, light, temperature, etc.) need to be digitized for processing, storage, or transmission.
The ADC captures a snapshot of an analog voltage at a specific moment and produces a digital output code that represents this voltage. The resolution of an ADC, determined by the number of bits used, affects how accurately it can represent the analog signal. For instance, a 4-bit ADC has a resolution of 1 in 15, while an 8-bit ADC has a resolution of 1 in 255.
The conversion process can be achieved through various methods, including parallel encoding (flash ADCs), which use multiple comparators to detect different voltage levels and output their states to an encoder. Flash ADCs are simple to construct and provide fast conversion without needing timing clocks.
For example, a simple 2-bit ADC requires three comparators to produce four distinct digital outputs based on the input voltage. As the input voltage changes, the comparators output HIGH or LOW signals, which are then encoded into a binary format. Increasing the resolution (e.g., to a 3-bit ADC) requires more comparators and allows for finer voltage measurements.
While higher resolution ADCs require more complex circuitry, they offer faster real-time conversion rates, making them suitable for various applications. Additionally, the process can be reversed using Digital-to-Analog Converters (DACs), which convert digital binary codes back into analog signals for controlling devices like motors or audio systems.
Simulate 2-Bit ADC with priority encoder
🧠Simulation : 3-bit ADC