2.3.3.3.65. NXphase_lock_loop

Status:

base class (contribution), extends NXcomponent

Description:

A base class definition for a phase-locked loop (PLL) used in AFM experiments. ...

A base class definition for a phase-locked loop (PLL) used in AFM experiments.

The PLL has three main components:

  1. Phase-detector

  2. Loop-filter

  3. Voltage-controlled oscillator (VCO)

Depending on the phase error from the phase detector due to the phase difference between the Reference and output from the VCO signals, the PLL adjusts the output frequency to minimize the phase error.

Measuring the phase error, the PLL can be in one of three states:

  • Zero phase error: The output signal is in coherence with the reference signal (lock condition).

  • Constant phase error: The output signal has a constant phase difference from the reference signal, and therefore,

    both reference signals have the same frequency (lock condition).

  • Continuous increasing phase error: The output signal’s phase continuously changes therefore they have different frequencies,

    indicating the PLL is in an unlock condition.

Symbols:

No symbol table

Groups cited:

NXcalibration, NXcomponent, NXfabrication

Structure:

center_frequency: (optional) NX_NUMBER {units=NX_FREQUENCY}

The center frequency of the PLL is the middle frequency of the PLL's operating ...

The center frequency of the PLL is the middle frequency of the PLL’s operating range.

frequency_bandwidth: (optional) NX_NUMBER {units=NX_FREQUENCY}

The frequency bandwidth of the PLL is where it responds or is stable. ...

The frequency bandwidth of the PLL is where it responds or is stable. If phase difference (also called phase error) is calculated from the input and output signal frequencies.

phase_bandwidth: (optional) NX_NUMBER {units=NX_FREQUENCY}

The phase bandwidth of the PLL is where it responds or is stable. ...

The phase bandwidth of the PLL is where it responds or is stable. If phase difference (also called phase error) is calculated from the input and output signal phases.

frequency_step: (optional) NX_NUMBER {units=NX_FREQUENCY}

The frequency step size of the PLL determines the resolution of frequency ...

The frequency step size of the PLL determines the resolution of frequency changes.

hardware: (optional) NXfabrication ⤆

Manufacturer and model of the PLL hardware or controller.

type: (optional) NX_CHAR

Types (design parameter for circuit) of the PLL from type-1, type-2, and typ ...

Types (design parameter for circuit) of the PLL from type-1, type-2, and type-3 available in device specifications (for mathematical details: https://www.nxp.com/docs/en/application-note/AN535.pdf). Type is defined by the number of poles that exist in the transfer function of the PLL.

Any of these values: type-1 | type-2 | type-3

order: (optional) NX_NUMBER {units=NX_UNITLESS}

Order of the PLL. This is characteristic of circuit design and is defined as ...

Order of the PLL. This is characteristic of circuit design and is defined as the number of roots of characteristics polynomial of the PLL circuit.

calibration: (optional) NXcalibration

Calibration information for the PLL, including any relevant parameters ...

Calibration information for the PLL, including any relevant parameters or procedures.

phase_detector: (optional) NXcomponent

The phase detector component of the PLL, which compares the phase between the ...

The phase detector component of the PLL, which compares the phase between the reference signal generated (e.g., in AFM, generated by the cantilever) and the signal coming from the VCO.

reference_frequency: (optional) NX_NUMBER {units=NX_FREQUENCY}

The input reference frequency to the PLL through the component Phase-detector.

frequency_shift: (optional) NX_NUMBER {units=NX_FREQUENCY}

Measured or target shift in oscillation from the VCO. relative to the refere ...

Measured or target shift in oscillation from the VCO. relative to the reference signal.

reference_phase: (optional) NX_NUMBER {units=NX_ANGLE}

Reference phase of the input signal to the phase detector.

phase_error: (optional) NX_NUMBER {units=NX_ANGLE}

Measured phase error (also called phase difference) between the reference si ...

Measured phase error (also called phase difference) between the reference signal and the VCO output.

Kp_coefficient: (optional) NX_NUMBER {units=V/rad}

The gain coefficient of the phase detector which determines how much the out ...

The gain coefficient of the phase detector which determines how much the output voltage changes in response to a phase difference (V/rad).

loop_filter: (optional) NXcomponent

The loop filter component of the PLL filters the voltage from the phase detect ...

The loop filter component of the PLL filters the voltage from the phase detector to the VCO. It extracts the average voltage of the phase error signals emitted from the phase detector.

Kf_coefficient: (optional) NX_NUMBER {units=NX_UNITLESS}

The Kf coefficient, called loop filter gain, determines the gain of the ...

The Kf coefficient, called loop filter gain, determines the gain of the loop filter circuit in the PLL.

voltage_controlled_oscillator: (optional) NXcomponent

The voltage-controlled oscillator (VCO) component of the PLL, which generates ...

The voltage-controlled oscillator (VCO) component of the PLL, which generates the output signal based on the filtered voltage from the loop filter.

output_frequency_range: (optional) NX_NUMBER {units=NX_FREQUENCY}

The output frequency range (written in an array of frequencies as [min, max] ...

The output frequency range (written in an array of frequencies as [min, max]) of the VCO which is the range of frequencies it can generate. The range is either the same as the frequency bandwidth of the PLL or shorter and inside that.

Kn_coefficient: (optional) NX_NUMBER {units=NX_UNITLESS}

The Kn coefficient, called the input-output frequency ratio, relates the inp ...

The Kn coefficient, called the input-output frequency ratio, relates the input frequency to the output frequency of the VCO. This coefficient is used to adjust the output frequency based on the input frequency.

Ko_coefficient: (optional) NX_NUMBER {units=NX_ANY}

The output voltage coefficient of the VCO, which determines how much the out ...

The output voltage coefficient of the VCO, which determines how much the output frequency changes in response to a change in input voltage (Hz/V).

Hypertext Anchors

List of hypertext anchors for all groups, fields, attributes, and links defined in this class.

NXDL Source:

https://github.com/FAIRmat-NFDI/nexus_definitions/tree/fairmat/contributed_definitions/NXphase_lock_loop.nxdl.xml