National Instruments pxi ni 5401 用户手册
Chapter 2
Function Generator Operation
©
National Instruments Corporation
2-13
Analog Filter Correction
The NI 5401 can correct for slight deviations in the flatness of the
frequency characteristic of the analog lowpass filter in its passband, as
shown in Figure 2-13. Curve A shows a typical lowpass filter curve. The
response of the filter is stored in an onboard EEPROM in 1 MHz
increments up to 16 MHz. Curve C is the correction applied to the
frequency response. The resulting Curve B is a flat response over the entire
passband. If you want to generate a sine wave at a particular frequency with
filter correction applied, you have to specify that frequency through your
software.
frequency characteristic of the analog lowpass filter in its passband, as
shown in Figure 2-13. Curve A shows a typical lowpass filter curve. The
response of the filter is stored in an onboard EEPROM in 1 MHz
increments up to 16 MHz. Curve C is the correction applied to the
frequency response. The resulting Curve B is a flat response over the entire
passband. If you want to generate a sine wave at a particular frequency with
filter correction applied, you have to specify that frequency through your
software.
Figure 2-13. Analog Filter Correction
Note
You can change the filter frequency correction at any time during waveform
generation.
A
B
C
Frequency (MHz)
Gain (dB)
A. Typical Analog Filter Characteristics
B. Corrected Filter Characteristics
C. Correction Applied
B. Corrected Filter Characteristics
C. Correction Applied