What Are Sampling Rate and Resolution?
Two basic values set the quality of an ADC or DAC: the sampling rate (how often in time) and the resolution (how fine in amplitude).
Sampling Rate
It shows how many times per second the signal is measured; its unit is samples/second (Sa/s) or Hz. Fast-changing signals need high sampling; for example, CD audio quality is 44,100 samples/second.
The Nyquist Theorem
To capture a signal correctly, the sampling rate must be at least twice the signal's highest frequency. Below this limit, aliasing (false frequencies) occurs and the signal is corrupted.
Resolution (Bit Depth)
It's how many bits represent each sample. n bits means 2ⁿ different levels: 8-bit is 256, 12-bit is 4096, 16-bit is 65,536 levels. Higher resolution provides finer amplitude distinction.
| Concept | Sets |
|---|---|
| Sampling rate | Time axis (frequency) |
| Resolution | Amplitude axis (fineness) |
The Two Together
For a good conversion both must be adequate: a high-frequency but low-resolution measurement stays coarse; a high-resolution but slow measurement misses fast changes. Both also increase the amount of data.
Common Mistakes
- Aliasing: sampling below Nyquist produces false frequencies.
- Overdoing it: higher-than-needed rate/resolution creates needless data and cost.
- Skipping the filter: an anti-alias filter should be placed before sampling.
Frequently Asked Questions
What is the Nyquist frequency?+
Which matters more, resolution or rate?+
Search parts related to "What Are Sampling Rate and Resolution?"
Find the right part by comparing price, stock and distributors.