Ejemplo n.º 1
0
 def simulate(self):
     self.netlist.to_spice('optimize.sp')
     ngspyce.source('optimize.sp')
     ngspyce.ac(**self.sim_params)
     fs = np.abs(ngspyce.vector('frequency'))
     vs = ngspyce.vector('vout')
     return fs, vs
Ejemplo n.º 2
0
def sim():
    tb = testbench(common_emitter_amplifer())
    circuit = Builder(tb).compile()
    circuit.to_spice('common_emitter_amplifier.sp')
    ng.source('common_emitter_amplifier.sp')
    ng.cmd('tran 50us 10ms')

    print('\n'.join(ng.vector_names()))
    time, tp1 = map(ng.vector, ['time', 'V(VOUT)'])
    plt.plot(time, tp1, label='VOUT')
    plt.legend()
    plt.show()
Ejemplo n.º 3
0
import subprocess
import os
import sys
from matplotlib.colors import SymLogNorm

#include store.py
import sys

sys.path.append('/home/arthurdent/covidinator/electronics/')
import store

import ngspyce

source_file = 'oscillator.cir'

ngspyce.source(source_file)


def run_sim(varactor_voltage):

    ngspyce.cmd(f'alterparam varactor_bias_voltage = {varactor_voltage}')
    ngspyce.cmd('reset')
    # ngspyce.cmd('stop after 10000')
    step_ps = 1  #not always obeyed - ngspice sets its own timestep.
    sim_duration = 100000
    n_steps = sim_duration / step_ps
    # ngspyce.cmd(" ")
    ngspyce.cmd(f'tran {step_ps}p {sim_duration}ps uic')

    timesteps = ngspyce.vector('time')
    v_collector = ngspyce.vector('v(E1)')
Ejemplo n.º 4
0
"""
Plot output voltages of an operational amplifier quadrature oscillator
"""

import ngspyce
import numpy as np
from matplotlib import pyplot as plt

# Load netlist
ngspyce.source('quad.net')
# Simulate 10 ms
ngspyce.cmd('tran 12n 10m 1n')

# Read results
time, vsin, vcos = map(ngspyce.vector, ['time', 'Vsin', 'Vcos'])
# And plot them
plt.plot(time * 1e3, vcos, label='Vcos')
plt.plot(time * 1e3, vsin, label='Vsin')

plt.title('Quadrature op-amp oscillator output voltage')
plt.xlabel('Time [ms]')
plt.ylabel('Voltage [V]')
plt.savefig('quad.png')
plt.show()
Ejemplo n.º 5
0
"""
Plot the output characteristics for the BC337 NPN transistor
"""

import ngspyce
import numpy as np
from matplotlib import pyplot as plt

# Load netlist
ngspyce.source('npn.net')

# Sweep both base and collector current
ngspyce.cmd('dc vcc 0 2 .05 vbb .7 1.2 .1')

# Load simulation results into numpy arrays
vb, vc, Ivcc = map(ngspyce.vector, ['Vb', 'Vc', 'I(Vcc)'])

# Correct the sign for collector current
ic = -Ivcc

plt.figure()
# Plot one line per base voltage
series = np.unique(vb)
for _vb in series:
    plt.plot(vc[vb == _vb],
             ic[vb == _vb],
             '-',
             label='Vb = {:.1f}'.format(_vb))

plt.legend()
plt.title('Output characteristics for BC337')
Ejemplo n.º 6
0
write_outfile = '-p' in sys.argv or '--pdf' in sys.argv
do_plot_thd = '-t' in sys.argv or '--thd' in sys.argv
do_plot_bode = '-b' in sys.argv or '--bode' in sys.argv
do_plot_bode_resonance = '-r' in sys.argv or '--bode-resonance' in sys.argv
TWO_STAGE_AMP = '-2' in sys.argv or '--two-stage' in sys.argv
PREGAIN = 21 if ('-i' in sys.argv
                 or '--instrumentation-amplifier' in sys.argv) else 1
infile = [arg for arg in sys.argv[1:] if arg[0] != '-'][0]
thd_outfile = os.path.splitext(infile)[0] + "_thd" + ("_DRAFT" if DRAFT_MODE
                                                      else "") + ".pdf"
bode_outfile = os.path.splitext(infile)[0] + "_bode" + ("_DRAFT" if DRAFT_MODE
                                                        else "") + ".pdf"
bode2_outfile = os.path.splitext(infile)[0] + "_bode_reso" + (
    "_DRAFT" if DRAFT_MODE else "") + ".pdf"

ns.source(infile)
plt.rcParams.update({'font.size': 8})

if do_plot_thd:
    plot_thd_grid(thd_outfile if write_outfile else None)

if do_plot_bode:
    plot_bode(bode_outfile if write_outfile else None)

if do_plot_bode_resonance:
    plot_bode2(bode2_outfile if write_outfile else None)

if not write_outfile:
    plt.show()

exit(0)
Ejemplo n.º 7
0
"""
Plot the frequency response of an RC low-pass filter
"""

import ngspyce
from matplotlib import pyplot as plt
import numpy as np

# Read netlist
ngspyce.source('lowpass.net')

# Calculate small-signal transfer function between 1 kHz and 10 MHz, with 5
# points per decade
ngspyce.ac(mode='dec', npoints=7, fstart=1e3, fstop=10e6)

# Read results
freq = np.abs(ngspyce.vector('frequency'))
vout = ngspyce.vector('vout')

# And plot them
fig, (ax1, ax2) = plt.subplots(2, sharex=True)
fig.suptitle('Frequency response of an RC low-pass filter')

ax1.semilogx(freq, 20 * np.log10(np.abs(vout)))
ax1.set_ylabel('Magnitude [dB]')
ax1.grid(True, which='both')

ax2.semilogx(freq, np.angle(vout, True))
ax2.set_xlabel('Frequency [Hz]')
ax2.set_ylabel('Phase [degrees]')
ax2.grid(True, which='both')
Ejemplo n.º 8
0
"""
Plot output voltages of an operational amplifier quadrature oscillator
"""

import ngspyce
import numpy as np
from matplotlib import pyplot as plt

# Load netlist
ngspyce.source('quad.net')
# Simulate 10 ms
ngspyce.cmd('tran 12n 10m 1n')

# Read results
time, vsin, vcos = map(ngspyce.vector, ['time', 'Vsin', 'Vcos'])
# And plot them
plt.plot(time*1e3, vcos, label='Vcos')
plt.plot(time*1e3, vsin, label='Vsin')

plt.title('Quadrature op-amp oscillator output voltage')
plt.xlabel('Time [ms]')
plt.ylabel('Voltage [V]')
plt.savefig('quad.png')
plt.show()
Ejemplo n.º 9
0
 def test_source(self):
     ns.source(os.path.join(os.path.dirname(__file__),
                            '../examples/npn/npn.net'))
     self.assertEqual(ns.model_parameters(model='QBC337AP')['bf'], 175)
Ejemplo n.º 10
0
"""
Plot the frequency response of an RC low-pass filter
"""

import ngspyce
from matplotlib import pyplot as plt
import numpy as np

# Read netlist
ngspyce.source('lowpass.net')

# Calculate small-signal transfer function between 1 kHz and 10 MHz, with 5
# points per decade
ngspyce.ac(mode='dec', npoints=7, fstart=1e3, fstop=10e6)

# Read results
freq = np.abs(ngspyce.vector('frequency'))
vout = ngspyce.vector('vout')

# And plot them
fig, (ax1, ax2) = plt.subplots(2, sharex=True)
fig.suptitle('Frequency response of an RC low-pass filter')

ax1.semilogx(freq, 20*np.log10(np.abs(vout)))
ax1.set_ylabel('Magnitude [dB]')
ax1.grid(True, which='both')

ax2.semilogx(freq, np.angle(vout, True))
ax2.set_xlabel('Frequency [Hz]')
ax2.set_ylabel('Phase [degrees]')
ax2.grid(True, which='both')
Ejemplo n.º 11
0
"""
Plot the output characteristics for the BC337 NPN transistor
"""

import ngspyce
import numpy as np
from matplotlib import pyplot as plt

# Load netlist
ngspyce.source('npn.net')

# Sweep both base and collector current
ngspyce.cmd('dc vcc 0 2 .02 vbb .7 1.2 .1')

# Load simulation results into numpy arrays
vb, vc, Ivcc = map(ngspyce.vector, ['Vb', 'Vc', 'I(Vcc)'])

# Correct the sign for collector current
ic = -Ivcc

plt.figure()
# Plot one line per base voltage
series = np.unique(vb)
for _vb in series:
    plt.plot(vc[vb == _vb], ic[vb == _vb], '-',
             label='Vb = {:.1f}'.format(_vb))

plt.legend(loc='center right')
plt.title('Output characteristics for BC337')
plt.xlabel('Collector-emitter voltage [V]')
plt.ylabel('Collector current [A]')