Integer N PLL with Dual Modulus Prescaler
Frequency synthesizer with dual modulus prescaler based integer N PLL architecture
Libraries:
Mixed-Signal Blockset /
PLL /
Architectures
Description
The Integer N PLL with Dual Modulus Prescaler reference architecture uses a Dual Modulus Prescaler block as the frequency divider in a PLL system. The frequency divider divides the frequency of the VCO output signal by an integer value to make it comparable to a PFD reference signal frequency.
Ports
Input
clk in — Input clock signal
scalar
Input clock signal, specified as a scalar. The signal at the clk in port is used as the reference signal for the PFD block in a PLL system.
Data Types: double
Output
clk out — Output clock signal
scalar
Output clock signal, specified as a scalar. The signal at the clk out port is the output of the VCO block in a PLL system.
Data Types: double
Parameters
Edit System — Break library block links and replace internal variables by appropriate values
button
Click to break the block links to the library. The internal variables are replaced by their values and the block becomes a simple subsystem.
Enable increased buffer size — Enable increased buffer size
button
Select to enable increased buffer size during the simulation. This increases the buffer size of all the building blocks in the PLL model that belong to the Mixed-Signal Blockset™/PLL/Building Blocks Simulink® library. The building blocks are PFD, Charge Pump, Loop Filter, VCO, and Dual Modulus Prescaler. By default, this option is deselected.
Buffer size for loop filter — Buffer size for loop filter
1000
(default) | positive integer scalar
Buffer size for the loop filter, specified as a positive integer scalar. This sets the number of extra buffer samples available during the simulation to the Convert Sample Time subsystem inside the loop filter.
Selecting different simulation solver or sampling strategies can change the number of input samples needed to produce an accurate output sample. Set the Buffer size for loop filter to a large enough value so that the input buffer contains all the input samples required.
Dependencies
This parameter is only available when the Enable increased buffer size option is selected.
Programmatic Use
Use
get_param(gcb,'NBufferFilter')
to view the current value of Buffer size for loop filter.Use
set_param(gcb,'NBufferFilter',value)
to set Buffer size for loop filter to a specific value.
Buffer size for PFD, charge pump, VCO, prescaler — Buffer size for PFD, charge pump, VCO, and prescaler
10
(default) | positive integer scalar
Buffer size for the PFD, charge pump, VCO, and prescaler, specified as a positive integer scalar. This sets the buffer size of the PFD, Charge Pump, VCO, and Dual Modulus Prescaler blocks inside the PLL model.
Selecting different simulation solver or sampling strategies can change the number of input samples needed to produce an accurate output sample. Set the Buffer size for PFD, charge pump, VCO, prescaler to a large enough value so that the input buffer contains all the input samples required.
Dependencies
This parameter is only available when the Enable increased buffer size option is selected.
Programmatic Use
Use
get_param(gcb,'NBuffer')
to view the current value of Buffer size for PFD, charge pump, VCO, prescaler.Use
set_param(gcb,'NBuffer',value)
to set Buffer size for PFD, charge pump, VCO, prescaler to a specific value.
PFD
ConfigurationDeadband compensation (s) — Delay added for active output near zero phase offset
40e-12
(default) | positive real scalar
Delay added for active output near zero phase offset, specified as a positive real scalar in seconds. Deadband is the phase offset band near zero phase offset for which the PFD output is negligible.
Programmatic Use
Use
get_param(gcb,'DeadbandCompensation')
to view the current value of Deadband compensation (s).Use
set_param(gcb,'DeadbandCompensation',value)
to set Deadband compensation (s) to a specific value.
Data Types: double
Enable impairments — Add circuit impairments to simulation
off (default) | on
Select to add circuit impairments such as rise/fall time and propagation delay to simulation. By default, this option is deselected.
Output step size calculation — Determine how output step size is calculated
Default
(default) | Advanced
Determine how output step size is calculated:
Select
Default
to calculate output step size from rise/fall time. Output step size (ΔT) is given by .Select
Advanced
to calculate output step size from maximum frequency of interest. Output step size (ΔT) is given by .
Dependencies
To enable this parameter, select Enable Impairments in the PFD tab.
Maximum frequency of interest (Hz) — Maximum frequency of interest at output
10e9
(default) | positive real scalar
Maximum frequency of interest at the output, specified as a positive real scalar in Hz.
Dependencies
To enable this parameter, select Enable Impairments in the PFD tab and choose Advanced for Output step size calculation.
Programmatic Use
Use
get_param(gcb,'MaxFreqInterest')
to view the current value of Maximum frequency of interest (Hz).Use
set_param(gcb,'MaxFreqInterest',value)
to set Maximum frequency of interest (Hz) to a specific value.
Data Types: double
Rise/fall time (s) — 20% – 80% rise/fall time for up output port of PFD
3e-11
(default) | positive real scalar
20% – 80% rise/fall time for the up output port of the PFD, specified as a positive real scalar in seconds.
Dependencies
To enable this parameter, select Enable Impairments in the PFD tab.
Programmatic Use
Use
get_param(gcb,'RiseFallTime')
to view the current value of Rise/fall time (s).Use
set_param(gcb,'RiseFallTime',value)
to set Rise/fall time (s) to a specific value.
Data Types: double
Propagation Delay (s) — Delay from input port to output port of PFD
50e-12
(default) | positive real scalar
Delay from the input port to output port of the PFD, specified as a positive real scalar in seconds.
Dependencies
To enable this parameter, select Enable Impairments in the PFD tab.
Programmatic Use
Use
get_param(gcb,'PropDelay')
to view the current value of Propagation Delay (s).Use
set_param(gcb,'PropDelay',value)
to set Propagation Delay (s) to a specific value.
Data Types: double
Charge pump
ConfigurationOutput current (A) — Design output current
1e-3
(default) | positive real scalar
Full scale magnitude of design output current, specified as a positive real scalar in amperes. This parameter is also reported as Charge pump current in the Loop Filter tab and is used to automatically calculate the filter component values of the loop filter. This parameter is tunable.
Programmatic Use
Block parameter:
OutputCurrent |
Type: character vector |
Values: positive real scalar |
Default:
1e-3 |
Data Types: double
Input threshold (V) — Logic switching threshold at input ports
0.5
(default) | real scalar
Logic switching threshold at input ports, specified as a real scalar in volts.
Programmatic Use
Use
get_param(gcb,'InputThreshold')
to view the current value of Input threshold (V).Use
set_param(gcb,'InputThreshold',value)
to set Input threshold (V) to a specific value.
Data Types: double
Enable current impairments — Add current impairments to simulation
off (default) | on
Select to add current impairments such as current imbalance and leakage current to simulation. By default, this option is deselected.
Current imbalance (A) — Difference between full scale positive and negative current
1e-7
(default) | positive real scalar
Difference between full scale positive and negative current, specified as a positive real scalar in amperes.
Dependencies
To enable this parameter, select Enable current impairments in the Charge pump tab.
Programmatic Use
Use
get_param(gcb,'CurrentImbalance')
to view the current value of Current imbalance (A).Use
set_param(gcb,'CurrentImbalance',value)
to set Current imbalance (A) to a specific value.
Data Types: double
Leakage current (A) — Output current without any input
1e-8
(default) | nonnegative real scalar
Output current when both inputs are at logic zero, specified as a nonnegative real scalar in amperes.
Dependencies
To enable this parameter, select Enable current impairments in the Charge pump tab.
Programmatic Use
Use
get_param(gcb,'LeakageCurrent')
to view the current value of Leakage current (A).Use
set_param(gcb,'LeakageCurrent',value)
to set Leakage current (A) to a specific value.
Data Types: double
Enable timing impairments — Add timing impairments to simulation
off (default) | on
Select to add timing impairments such as rise/fall time and propagation delay to simulation. By default, this option is deselected.
Output step size calculation — Determine how output step size is calculated
Default
(default) | Advanced
Determine how output step size is calculated:
Select
Default
to calculate output step size from rise/fall time. Output step size (ΔT) is given by .Select
Advanced
to calculate output step size from maximum frequency of interest. Output step size (ΔT) is given by .
Dependencies
To enable this parameter, select Enable timing impairments in the Charge Pump tab.
Maximum frequency of interest (Hz) — Maximum frequency of interest at output
10e9
(default) | positive real scalar
Maximum frequency of interest at the output, specified as a positive real scalar in Hz.
Dependencies
To enable this parameter, select Enable timing impairments in the Charge Pump tab and choose Advanced for Output step size calculation.
Programmatic Use
Use
get_param(gcb,'MaxFreqInterestCp')
to view the current value of Maximum frequency of interest (Hz).Use
set_param(gcb,'MaxFreqInterestCp',value)
to set Maximum frequency of interest (Hz) to a specific value.
Data Types: double
Rise/fall time (s) — 20% – 80% rise/fall time for up input port
5e-9
(default) | positive real scalar
20% – 80% rise/fall time for the up input port of the charge pump, specified as a positive real scalar in seconds.
Dependencies
To enable this parameter, select Enable timing impairments in the Charge pump tab.
Programmatic Use
Use
get_param(gcb,'RiseFallUp')
to view the current value of Up Rise/fall time (s).Use
set_param(gcb,'RiseFallUp',value)
to set Up Rise/fall time (s) to a specific value.
Data Types: double
Propagation delay (s) — Total propagation delay from up input port to output port of charge pump
6e-9
(default) | positive real scalar
Total propagation delay from the up input port to output port of the charge pump, specified as a positive real scalar in seconds.
Dependencies
To enable this parameter, select Enable timing impairments in the Charge pump tab.
Programmatic Use
Use
get_param(gcb,'PropDelayUp')
to view the current value of Up Propagation delay (s).Use
set_param(gcb,'PropDelayUp',value)
to set Up Propagation delay (s) to a specific value.
Data Types: double
Rise/fall time — 20% – 80% rise/fall time for down input port
2e-9
(default) | scalar
20% – 80% rise/fall time for down input port of charge pump.
Dependencies
To enable this parameter, select Enable timing impairments in the Charge pump tab.
Programmatic Use
Use
get_param(gcb,'RiseFallDown')
to view the current value of Down Rise/fall time (s).Use
set_param(gcb,'RiseFallDown',value)
to set Down Rise/fall time (s) to a specific value.
Data Types: double
Propagation delay (s) — Total propagation delay from up input port to output port of charge pump
4e-9
(default) | positive real scalar
Total propagation delay from the up input port to output port of the charge pump, specified as a positive real scalar in seconds.
Dependencies
To enable this parameter, select Enable timing impairments in the Charge pump tab.
Programmatic Use
Use
get_param(gcb,'PropDelayUp')
to view the current value of Down Propagation delay (s).Use
set_param(gcb,'PropDelayUp',value)
to set Down Propagation delay (s) to a specific value.
Data Types: double
VCO
Specify using — Define how VCO output frequency is specified
Voltage sensitivity
(default) | Output frequency vs. control voltage
Define how VCO output frequency is specified:
Select
Voltage sensitivity
to specify output frequency from Voltage sensitivity (Hz/V) and Free running frequency (Hz).Select
Output frequency vs. control voltage
to interpolate output frequency from Control voltage (V) vector versus Output frequency (Hz) vector.
Programmatic Use
Block parameter:
SpecifyUsing |
Type: character vector |
Values:
Voltage sensitivity | Output frequency
vs. control voltage |
Default:
Voltage sensitivity |
Voltage sensitivity (Hz/V) — Measure of change in output frequency of VCO
100e6
(default) | positive real scalar
Measure of change in output frequency for input voltage change, specified as a positive real scalar with units in Hz/V. This parameter is also reported as VCO voltage sensitivity in the Loop Filter tab and is used to automatically calculate the filter component values of the loop filter.
Dependencies
To enable this parameter, select Voltage sensitivity
in
Specify using in the VCO tab.
Programmatic Use
Block parameter:
Kvco |
Type: character vector |
Values: positive real scalar |
Default:
100e6 |
Data Types: double
Free running frequency (Hz) — VCO output frequency without control voltage
1.8e9
(default) | positive real scalar
Frequency of the VCO without any control voltage input (0
V), or
the quiescent frequency, specified as a positive real scalar in Hz.
Dependencies
To enable this parameter, select Voltage sensitivity
in
Specify using in the VCO tab.
Programmatic Use
Block parameter:
Fo |
Type: character vector |
Values: positive real scalar |
Default:
1.8e9 |
Data Types: double
Control voltage (V) — Control voltage values
[-5 0 5]
(default) | real valued vector
Control voltage values of the VCO, specified as a real valued vector in volts.
Dependencies
To enable this parameter, select Output frequency vs. control
voltage
in Specify using in the
VCO tab.
Programmatic Use
Block parameter:
ControlVoltage |
Type: character vector |
Values: real valued vector |
Default:
[-5 0 5] |
Data Types: double
Output frequency (Hz) — VCO output frequency values
[2e9 2.5e9 3e9]
(default) | real valued vector
Output frequency of the values of the VCO, corresponding to the Control voltage (V) vector, specified in Hz.
Dependencies
To enable this parameter, select Output frequency vs. control
voltage
in Specify using in the
VCO tab.
Programmatic Use
Block parameter:
OutputFrequency |
Type: character vector |
Values: real valued vector |
Default:
[2e9 2.5e9 3e9] |
Data Types: double
Output amplitude — Maximum amplitude of VCO output voltage
1
(default) | positive real scalar
Maximum amplitude of the VCO output voltage, specified as a positive real scalar.
Programmatic Use
Block parameter:
Amplitude |
Type: character vector |
Values: positive real scalar |
Default:
1 |
Data Types: double
Add phase noise — Add phase noise as function of frequency
off (default) | on
Select to introduce phase noise as a function of frequency to the VCO. By default, this option is deselected.
Phase noise frequency offset (Hz) — Frequency offsets of phase noise from carrier frequency
[10e3 100e3 1e6 3e6 10e6]
(default) | real valued vector
Frequency offsets of the phase noise from the carrier frequency, specified as a real valued vector in Hz.
Dependencies
To enable this parameter, select Add phase noise in the VCO tab.
Programmatic Use
Block parameter:
Foffset |
Type: character vector |
Values: real valued vector |
Default:
[10e3 100e3 1e6 3e6 10e6] |
Data Types: double
Phase noise level (dBc/Hz) — Phase noise power at specified frequency offsets relative to the carrier
[-77 -108 -134 -145 -154]
(default) | real valued vector
Real valued vector specifying the phase noise power in a 1 Hz bandwidth centered at the specified frequency offsets relative to the carrier. The value is specified in dBc/Hz.
Dependencies
To enable this parameter, select Add phase noise in the VCO tab.
Programmatic Use
Block parameter:
PhaseNoise |
Type: character vector |
Values: real valued vector |
Default:
[-77 -108 -134 -145 -154] |
Data Types: double
Estimate phase noise parameters — Automatically estimate phase noise parameters
on (default) | off
Select to automatically estimate the phase noise parameters. By default, this option is selected.
You can deselect this option to define custom period jitter and flicker corner frequency.
Dependencies
To enable this parameter, select Add phase noise in the VCO tab.
Data Types: double
Period jitter (S) — Standard deviation of period jitter
2.6794e-15
(default) | positive real scalar
Standard deviation of the period jitter, specified as a positive real scalar in seconds. Period jitter is the deviation in cycle time of a clock signal with respect to the ideal period.
To enable this parameter, select Add phase noise and deselect Estimate phase noise parameters in the VCO tab.
Programmatic Use
Block parameter:
PeriodJitter |
Type: character vector |
Values: positive real scalar |
Default:
2.6794e-15 |
Data Types: double
Flicker corner frequency (Hz) — Corner frequency of flicker noise
517103.8168
(default) | scalar
Corner frequency of the flicker noise, specified as a scalar in hertz. Flicker corner frequency (Hz) is defined as the frequency at which the phase noise transitions from 1/f2 to 1/f3 due to flicker noise. At this frequency, the spectral densities of period jitter and flicker noise are equal.
Dependencies
To enable this parameter, select Add phase noise and deselect Estimate phase noise parameters in the VCO tab.
Programmatic Use
Block parameter:
CornerFrequency |
Type: character vector |
Values: scalar |
Default:
517103.8168 |
Data Types: double
Plot fit — Plot specified and expected VCO output phase noise density
button
Click to plot the specified phase noise density and realizable expected output phase noise density of the VCO.
Prescaler
Program counter value, P — Value of the program counter inside dual modulus prescaler
18
(default) | positive real scalar
Value of the program counter inside the dual modulus prescaler, specified as a positive real scalar. Program counter value, P is used to calculate the effective divider value. This parameter is tunable. For more information, see Dual Modulus Prescaler.
Programmatic Use
Use
get_param(gcb,'ProgramCounter')
to view the current Program counter value, P.Use
set_param(gcb,'ProgramCounter',value)
to set Program counter value, P to a specific value.
Data Types: double
Prescaler divider value, N — Value of the prescaler divider inside dual modulus prescaler
5
(default) | positive real scalar
Value of the prescaler divider inside the dual modulus prescaler, specified as a positive real scalar. Prescaler divider value, N is used to calculate the effective divider value. This parameter is tunable. For more information, see Dual Modulus Prescaler.
Programmatic Use
Use
get_param(gcb,'PrescalerDivider')
to view the current Prescaler divider value, N.Use
set_param(gcb,'PrescalerDivider',value)
to set Prescaler divider value, N to a specific value.
Data Types: double
Swallow counter value, S — Value of the swallow counter inside dual modulus prescaler
10
(default) | positive real scalar
Value of the swallow counter inside the dual modulus prescaler, specified as a positive real scalar. Swallow counter value, S is used to calculate the effective divider value. For more information, see Dual Modulus Prescaler.
Programmatic Use
Use
get_param(gcb,'SwallowCounter')
to view the current Swallow counter value, S.Use
set_param(gcb,'SwallowCounter',value)
to set Swallow counter value, S to a specific value.
Data Types: double
Min clock divider value — Minimum value by which clock divider can divide input frequency
100
(default) | positive real scalar
Minimum value by which the clock divider can divide input frequency, specified as a positive real scalar. This parameter is also reported in the Loop Filter tab and is used to automatically calculate the filter component values of the loop filter.
Programmatic Use
Use
get_param(gcb,'Nmin')
to view the current value of Min clock divider value.Use
set_param(gcb,'Nmin',value)
to set Min clock divider value to a specific value.
Data Types: double
Loop Filter
Filter component values — Determines how filter components are computed
Automatic
(default) | Manual
Select how filter components for the loop filter are computed:
Select
Automatic
to automatically compute filter components from system specifications. Resistance and capacitance edit boxes in the Loop Filter tab are not editable if this option is selected. Rather, the filter component values are calculated from Loop bandwidth (Hz), Phase margin (degrees), VCO voltage sensitivity, Charge pump current, and Min clock divider value. By default, this option is selected.Select
Manual
to manually enter the resistance and capacitance values to design a customized loop filter.
Loop bandwidth (Hz) — Frequency at which magnitude of open loop transfer function becomes 1
1e6
(default) | positive real scalar
Frequency at which the magnitude of the open loop transfer function becomes 1, specified as a positive real scalar in Hz.
As a rule of thumb, the loop bandwidth should be 1/10th of input reference clock. Lower values of Loop bandwidth (Hz) result in reduced phase noise and reference spurs at the expense of longer lock time and less phase margin.
Dependencies
This parameter is only available when Automatic
is
selected for the Filter Component values parameter in the
Loop Filter tab.
Programmatic Use
Use
get_param(gcb,'Fc')
to view the current value of Loop bandwidth (Hz).Use
set_param(gcb,'Fc',value)
to set Loop bandwidth (Hz) to a specific value.
Data Types: double
Phase margin (degrees) — Phase of open loop transfer function at loop bandwidth subtracted from 180°
45
(default) | positive real scalar
Phase of the open loop transfer function at the loop bandwidth subtracted from 180°, specified as a positive real scalar in degrees. For optimum lock time, select a phase margin between 40° and 55°.
Dependencies
This parameter is only available when Automatic
is
selected for the Filter Component values parameter in the
Loop Filter tab.
Programmatic Use
Use
get_param(gcb,'Phi')
to view the current value of Phase margin (degrees).Use
set_param(gcb,'Phi',value)
to set Phase margin (degrees) to a specific value.
Data Types: double
Loop filter type — Order of the loop filter
3rd Order Passive
(default) | 2nd Order Passive
| 4th Order Passive
Order of the loop filter. Applies a second-, third-, or fourth-order passive RC loop filter in the PLL system.
C1 (F) — Capacitance 1
5.24e-12
(default) | positive real scalar
Capacitor value C1, specified as a positive real scalar in farad.
Dependencies
This parameter is only editable when Manual
is selected
for the Filter Component values parameter in the Loop
Filter tab.
Programmatic Use
Use
get_param(gcb,'C1')
to view the current value of C1 (F).Use
set_param(gcb,'C1',value)
to set C1 (F) to a specific value.
Data Types: double
C2 (F) — Capacitance 2
5.77e-11
(default) | positive real scalar
Capacitor value C2, specified as a positive real scalar in farad.
Dependencies
This parameter is only editable when Manual
is selected
for the Filter Component values parameter in the Loop
Filter tab.
Programmatic Use
Use
get_param(gcb,'C2')
to view the current value of C2 (F).Use
set_param(gcb,'C2',value)
to set C2 (F) to a specific value.
Data Types: double
C3 (F) — Capacitance 3
3.76e-13
(default) | positive real scalar
Capacitor value C3, specified as a positive real scalar in farad.
Dependencies
To enable this parameter, select
3rd Order Passive
or4th Order Passive
in Loop filter type.This parameter is only editable when
Manual
is selected for the Filter Component values parameter in the Loop Filter tab.
Programmatic Use
Use
get_param(gcb,'C3')
to view the current value of C3 (F).Use
set_param(gcb,'C3',value)
to set C3 (F) to a specific value.
Data Types: double
C4 (F) — Capacitance 4
1e-12
(default) | positive real scalar
Capacitor value C4, specified as a positive real scalar in farad.
Dependencies
To enable this parameter, select
4th Order Passive
in Loop filter type.This parameter is only editable when
Manual
is selected for the Filter Component values parameter in the Loop Filter tab.
Programmatic Use
Use
get_param(gcb,'C4')
to view the current value of C4 (F).Use
set_param(gcb,'C4',value)
to set C4 (F) to a specific value.
Data Types: double
R2 (ohms) — Resistance 2
6.66e+03
(default) | positive real scalar
Resistor value R2, specified as a positive real scalar in ohms.
Dependencies
This parameter is only editable when Manual
is selected
for the Filter Component values parameter in the Loop
Filter tab.
Programmatic Use
Use
get_param(gcb,'R2')
to view the current value of R2 (ohms).Use
set_param(gcb,'R2',value)
to set R2 (ohms) to a specific value.
Data Types: double
R3 (ohms) — Resistance 3
8.51e+04
(default) | positive real scalar
Resistor value R3, specified as a positive real scalar in ohms.
Dependencies
To enable this parameter, select
3rd Order Passive
or4th Order Passive
in Loop filter type.This parameter is only editable when
Manual
is selected for the Filter Component values parameter in the Loop Filter tab.
Programmatic Use
Use
get_param(gcb,'R3')
to view the current value of R3 (ohms).Use
set_param(gcb,'R3',value)
to set R3 (ohms) to a specific value.
Data Types: double
R4 (ohms) — Resistance 4
12e3
(default) | positive real scalar
Resistor value R4, specified as a positive real scalar in ohms.
Dependencies
To enable this parameter, select
4th Order Passive
in Loop filter type.This parameter is only editable when
Manual
is selected for the Filter Component values parameter in the Loop Filter tab.
Programmatic Use
Use
get_param(gcb,'R4')
to view the current value of R4 (ohms).Use
set_param(gcb,'R4',value)
to set R4 (ohms) to a specific value.
Data Types: double
Enable impairments — Add circuit impairments to simulation
off (default) | on
Select to add circuit impairments such as operating temperature to determine thermal noise to simulation. By default, this option is deselected.
Operating temperature (℃) — Temperature to determine the level of thermal noise
30
(default) | real scalar
Temperature of the resistor, specified as a real scalar in ℃. Operating temperature determines the level of thermal (Johnson) noise.
Dependencies
To enable this parameter, select Enable impairments in the Loop Filter tab.
Programmatic Use
Use
get_param(gcb,'Temperature')
to view the current value of Operating temperature.Use
set_param(gcb,'Temperature',value)
to set Operating temperature to a specific value.
Data Types: double
Export Loop Filter Component Values — Export loop filter component values
button
Click to export loop filter component values to a spreadsheet (XLS file) or as comma-separated values (CSV file).
Probe
PFD up and PFD down (pfd_up and pfd_down) — Select to probe PFD outputs
off (default) | on
Select to probe the PFD output wires (pfd_up and pfd_down) to view the response of the PFD.
Charge pump output (cp_out) — Select to probe charge pump output
off (default) | on
Select to probe the charge pump output wire (cp_out) to view the response of the Charge Pump.
Loop filter output (lf_out) — Select to probe loop filter output
off (default) | on
Select to probe loop filter output wire (lf_out) to view the response of the Loop Filter. The loop filter output provides the control voltage to the VCO.
Prescaler output (ps_out) — Select to probe prescaler output
off (default) | on
Select to probe the prescaler output wire (ps_out) to view the response of the Fractional Clock Divider with Accumulator.
Analysis
Open Loop Analysis — Plot the presimulation open loop analysis
on (default) | off
Select to plot the gain margin and phase margin of the PLL system before simulation. By default, this option is selected.
Closed Loop Analysis — Plot the presimulation closed loop analysis
off (default) | on
Select to plot the pole-zero map, loop bandwidth, step response, and impulse response of the PLL system before simulation. You must have a license to Control System Toolbox™ to plot the step response and impulse response of the PLL system. By default, this option is deselected.
Plot Loop Dynamics — Plot loop dynamics of PLL system
button
Click to plot the presimulation loop dynamics of the PLL system.
Estimate phase noise — Estimate phase noise from input clock
off (default) | on
Select to estimate the phase noise from the input clock. By default, this option is deselected.
Reference frequency (Hz) — Reference frequency of input clock
10e6
(default) | positive real scalar
Reference frequency of input clock, specified as a positive real scalar.
Dependencies
To enable this parameter, select Estimate Phase Noise in the Analysis tab.
Programmatic Use
Block parameter:
RefFreq |
Type: character vector |
Values: positive real scalar |
Default:
10e6 |
Resolution bandwidth (Hz) — Smallest positive frequency that can be resolved
10e3
(default) | positive real scalar
Smallest positive frequency that can be resolved, specified as a real positive scalar. The Resolution bandwidth (Hz) is used to determine window length for spectral analysis using the Welch method. For more information, see Welch's Method of Averaged Modified Periodograms.
In general, Resolution bandwidth (Hz) should be less than the lowest offset frequency value.
Dependencies
To enable this parameter, select Estimate Phase Noise in the Analysis tab.
Programmatic Use
Block parameter:
Rbw |
Type: character vector |
Values: positive real scalar |
Default:
10e3 |
Frequency offset vector (Hz) — Frequency points relative to fundamental frequency where phase noise is calculated
[10e3 100e3 1e6 3e6 10e6]
(default) | real valued vector
Frequency points relative to fundamental frequency where phase noise is calculated, specified as a real valued vector in Hz.
Dependencies
To enable this parameter, select Estimate Phase Noise in the Analysis tab.
Programmatic Use
Block parameter:
FrOffset |
Type: character vector |
Values: real valued vector |
Default:
[10e3 100e3 1e6 3e6 10e6] |
Target phase-noise levels (dBc/Hz) — Target phase noise profile for given frequency offset vector
-inf
(default) | vector | scalar
Target phase noise profile for given frequency offset vector, specified in dBc/Hz. Target phase noise levels (dBc/Hz) is the phase noise power in a 1 Hz bandwidth centered at the specified frequency offsets relative to the carrier.
Dependencies
To enable this parameter, select Estimate Phase Noise in the Analysis tab.
Programmatic Use
Block parameter:
TargetPn |
Type: character vector |
Values: vector | scalar |
Default:
-inf |
Plot estimated phase noise — Plot estimated input clock phase noise
button
Click to plot the estimated input clock phase noise.
Version History
Introduced in R2019aR2023b: Estimate VCO Phase Noise Parameters
You can either estimate the phase noise parameters of the VCO, or manually define the custom period jitter and flicker corner frequency. You can also plot the specified and expected output phase noise density of the VCO.
See Also
PFD | Charge Pump | Loop Filter | Dual Modulus Prescaler | Ring Oscillator VCO
MATLAB 명령
다음 MATLAB 명령에 해당하는 링크를 클릭했습니다.
명령을 실행하려면 MATLAB 명령 창에 입력하십시오. 웹 브라우저는 MATLAB 명령을 지원하지 않습니다.
Select a Web Site
Choose a web site to get translated content where available and see local events and offers. Based on your location, we recommend that you select: .
You can also select a web site from the following list:
How to Get Best Site Performance
Select the China site (in Chinese or English) for best site performance. Other MathWorks country sites are not optimized for visits from your location.
Americas
- América Latina (Español)
- Canada (English)
- United States (English)
Europe
- Belgium (English)
- Denmark (English)
- Deutschland (Deutsch)
- España (Español)
- Finland (English)
- France (Français)
- Ireland (English)
- Italia (Italiano)
- Luxembourg (English)
- Netherlands (English)
- Norway (English)
- Österreich (Deutsch)
- Portugal (English)
- Sweden (English)
- Switzerland
- United Kingdom (English)