customs Namespace Reference

Contain the assembly functions for composite PLL circuits. More...

Functions
def	aPLL (compo, keys)
	Analog PLL composite circuit. More...
def	dPFD (compo, keys)
	Digital PLL composite circuit. More...
def	aAMPD (compo, keys)
	Analogue amplitude detection circuit. More...
def	LockInAmp (compo, keys)
	Lock in amplifier. More...

Detailed Description

Function Documentation

def customs.aAMPD	(		compo,
			keys
	)

Passed a singal throuhg a low pass filter to calculate the amplitude of it.

Initialisation parameters:

• fcut = Cut off frequency for the low pass filter

Input channels:

• signal = incoming signal

Output channels:

• amp = Amplitude of the incoming wave
• norm = normalaised input wave.

Example:

machine.AddCircuit(type="Machine",name='amp', fcut=10000, assembly=aAMPD, pushed=True)

def customs.aPLL	(		compo,
			keys
	)

Assembly function for analog PLL composite circuit. The Phase-Frequency Detector (PFD) multiplies the signals, and the result is passed to a series of lowpass Sallen-Key filters. The mount of filters and their cutoff frequencies are taken from the input parameter filters.

Note

For this to work, the output sin should be connected to signal2 in the parent circuit (as shown in example). Also, both signals should be normalised (amplitude = 1) and their offset should be removed.

schema

Initialisation parameters:

• filters = list of cutoff frequencies for PFD lowpass filters
• Kp = proportional constant of the charge pump
• Ki = integral constant of the charge pump
• gain = gain on the charge pump output
• pushed = True|False push the output buffer immediately if True

Input channels:

• signal1 = incoming signal
• signal2 = reference signal
• f0 = fundamental frequency

Output channels:

• sin = sine wave of the internal VCO
• cos = cosine wave of the internal VCO
• df = frequency shift from f0

Example:

machine = Machine(name='machine', dt=1.0e-8, pushed=True);

machine.AddCircuit(type="Machine",name='pll', assembly=aPLL, filters=[1000,500],
    gain=600.0, f0=1.0e5, Kp=0.4, Ki=500)

machine.Connect("pll.sin","pll.signal2")

def customs.dPFD	(		compo,
			keys
	)

Compares the delay between two flip flops becomoing positive allowing frequency shift between two signals to be measured.

Note

For this to work, the output sin should be connected to signal2 in the parent circuit (as shown in example). Also, both signals should be normalised (amplitude = 1) and their offset should be removed.

Initialisation parameters:

• fcut = Cutoff frequencies for dPFD lowpass filter
• Kp = proportional constant of the charge pump
• Ki = integral constant of the charge pump
• gain = gain on the charge pump output
• pushed = True|False push the output buffer immediately if True

Input channels:

• ref = incoming signal
• vco = reference signal
• f0 = fundamental frequency

Output channels:

• sin = sine wave of the internal VCO
• cos = cosine wave of the internal VCO
• df = frequency shift from f0

Example:

machine = Machine(name='machine', dt=1.0e-8, pushed=True);

machine.AddCircuit(type="Machine",name='pll', assembly=dPFD, filters=[1000,500],
 gain=600.0, f0=1.0e5, Kp=0.4, Ki=500)

machine.Connect("pll.sin","pll.signal2")

def customs.LockInAmp	(		compo,
			keys
	)

Calculates the complex phase shift and magnitude of a given signal

Initialisation parameters:

• fcut = Cut off frequency for the low pass filter
• intTime = Integration time of the lock in amp
• CentFreq = the central frequency of the lock in amp signal
• OutAmp = the outputted amplitude of the reference signal
• Gain = gain of the final outputted signal

Input channels:

• signal = incoming signal
• CentFreq = incoming signal

Output channels:

• amp = Complex magnitude of the signal.
• phase = Complex phase of the signal.
• refWave = the reference wave used in the lock in amp, oscilating at the central frequency.
• X = Real part of the complex output.
• Y = Imaginary part of the complex output.