Filtering
- Updated2025-06-30
- 1 minute(s) read
You can configure a filter for each bank on the FD-11634.
FieldDAQ supports three types of lowpass filtering:
- Brickwall (default)
- Butterworth
- Comb
| Attribute | Brickwall (Default) | Butterworth | Comb |
|---|---|---|---|
| Passband | Tracks sample rate | Configurable independent of sample rate | Tracks sample rate |
| Alias Protection | Best—Full protection | Better—Configurable protection level | Good—Partial protection |
| Latency | High | Medium to high (configuration-dependent) | Low |
| Input Delay Variation versus Frequency | Constant input delay | Variable input delay | Constant input delay |
| Flatness | Best | Best | Good |
| Step Response (Time Domain) | Most delay, ringing (overshoot/undershoot) | Mid-level delay, overshoot | Short delay, no overshoot/undershoot |
| Typical Applications |
Analyzing dynamic properties of signals Analyzing spectrum of signals |
Filtering out specific noise sources Analyzing signals in the time domain Reducing measurement noise |
Filtering out specific noise sources Analyzing signals in the time domain Control applications |
Configurable filtering is supported in NI-DAQmx 18.6 and later. Previous versions of NI-DAQmx support only brickwall filtering. Refer to the FD-11634 Specifications for details on the amount of variation in the response you can expect for different input frequency ranges.
Learn more about FieldDAQ filters.