NIRFSG_ATTR_LO_FREQUENCY_STEP_SIZE
- Updated2024-05-08
- 2 minute(s) read
NIRFSG_ATTR_LO_FREQUENCY_STEP_SIZE
| Numeric Value | Data type |
Access | Coercion | High Level Functions |
|---|---|---|---|---|
| 1150151 | ViReal64 | R/W | None | None |
Description
Specifies the step size for tuning the local oscillator (LO) phase-locked loop (PLL).
When the NIRFSG_ATTR_LO_PLL_FRACTIONAL_MODE_ENABLED attribute is enabled, the specified step size affects the fractional spur performance of the device. When the NIRFSG_ATTR_LO_PLL_FRACTIONAL_MODE_ENABLED attribute is disabled, the specified step size affects the phase noise performance of the device.
The valid values for this attribute depend on the NIRFSG_ATTR_LO_PLL_FRACTIONAL_MODE_ENABLED attribute.
PXIe-5644/5645/5646—If you disable the NIRFSG_ATTR_LO_PLL_FRACTIONAL_MODE_ENABLED attribute, the specified value is coerced to the nearest valid value.
PXIe-5840/5841—If you disable the NIRFSG_ATTR_LO_PLL_FRACTIONAL_MODE_ENABLED attribute, the specified value is coerced to the nearest valid value that is less than or equal to the desired step size.
| NIRFSG_ATTR_LO_PLL_FRACTIONAL_MODE_ENABLED Attribute Setting |
NIRFSG_ATTR_LO_FREQUENCY_STEP_SIZE Attribute Valid Values on PXIe-5644/5645 |
NIRFSG_ATTR_LO_FREQUENCY_STEP_SIZE Attribute Valid Values on PXIe-5646 |
NIRFSG_ATTR_LO_FREQUENCY_STEP_SIZE Attribute Valid Values on PXIe-5840/5841 |
NIRFSG_ATTR_LO_FREQUENCY_STEP_SIZE Attribute Valid Values on PXIe-5830/5831/5832 |
NIRFSG_ATTR_LO_FREQUENCY_STEP_SIZE Attribute Valid Values on PXIe-5841 with PXIe-5655* |
|
| LO1 | LO2 | |||||
| NIRFSG_VAL_ENABLE | 50 kHz to 24 MHz | 50 kHz to 25 MHz | 50 kHz to 100 MHz | 8 Hz to 400 MHz | 4 Hz to 400 MHz | 1 nHz to 50 MHz |
| NIRFSG_VAL_DISABLE | 4 MHz, 5 MHz, 6 MHz, 12 MHz, or 24 MHz | 2 MHz, 5 MHz, 10 MHz, or 25 MHz | 1 MHz, 5 MHz, 10 MHz, 25 MHz, 50 MHz, or 100 MHz | — | — | |
| * Values up to 100 MHz are coerced to 50 MHz. | ||||||
Units: hertz (Hz)
Default Values:
PXIe-5644/5645/5646: 200 kHz
PXIe-5830: 2 MHz
PXIe-5831/5832 (RF port): 8 MHz
PXIe-5831/5832 (IF port): 2 MHz, 4 MHz
PXIe-5840/5841:
- Fractional mode: 500 kHz
- Integer mode: 10 MHz for frequencies less than or equal to 4 GHz. 20 MHz for frequencies greater than 4 GHz.
PXIe-5841 with PXIe-5655: 500 kHz
Supported Devices: PXIe-5644/5645/5646, PXIe-5830/5831/5832/5840/5841