def nmos_characteristics(Vd, Vg):
circuit = Circuit('NMOS Input Characteristic')
circuit.include(
'./app/circuits/libraries/transistor/ptm_65nm_nmos_bulk.mod')
# Define the DC supply voltage value
Vdd = float(Vd)
# Instanciate circuit elements
Vgate = circuit.V('gate', 'gatenode', circuit.gnd, u_V(float(Vg)))
Vdrain = circuit.V('drain', 'vdd', circuit.gnd, u_V(Vdd))
# M <name> <drain node> <gate node> <source node> <bulk/substrate node>
circuit.MOSFET(1,
'vdd',
'gatenode',
circuit.gnd,
circuit.gnd,
model='ptm65nm_nmos')
simulator = circuit.simulator(temperature=25, nominal_temperature=25)
analysis = simulator.dc(Vdrain=slice(0, Vdd, .01))
figure, ax = plt.subplots(figsize=(20, 10))
ax.plot(analysis['vdd'], u_A(-analysis.Vdrain))
ax.legend('NMOS characteristic')
ax.grid()
ax.set_xlabel('Vds [V]')
ax.set_ylabel('Id [A]')
return circuit, analysis, plt
libraries_path = find_libraries()
spice_library = SpiceLibrary(libraries_path)
circuit = Circuit('NMOS Transistor')
circuit.include(spice_library['ptm65nm_nmos'])
# Define the DC supply voltage value
Vdd = 1.1
# Instanciate circuit elements
Vgate = circuit.V('gate', 'gatenode', circuit.gnd, 0 @ u_V)
Vdrain = circuit.V('drain', 'vdd', circuit.gnd, u_V(Vdd))
# M <name> <drain node> <gate node> <source node> <bulk/substrate node>
circuit.MOSFET(1,
'vdd',
'gatenode',
circuit.gnd,
circuit.gnd,
model='ptm65nm_nmos')
#r# We plot the characteristics :math:`Id = f(Vgs)` using a DC sweep simulation.
simulator = circuit.simulator(temperature=25, nominal_temperature=25)
analysis = simulator.dc(Vgate=slice(0, Vdd, .01))
figure, ax = plt.subplots(figsize=(20, 10))
ax.plot(analysis['gatenode'], u_mA(-analysis.Vdrain))
ax.legend('NMOS characteristic')
ax.grid()
ax.set_xlabel('Vgs [V]')
ax.set_ylabel('Id [mA]')
def define_circuit(self):
logger = Logging.setup_logging()
circuit_lab = self.circuit
circuit = Circuit(circuit_lab["name"])
# for complex circuit elements that requires SPICE library
# libraries_path = find_libraries()
python_file = os.path.abspath(sys.argv[0])
examples_root = parent_directory_of(python_file)
libraries_path = os.path.join(examples_root, 'libraries')
spice_library = SpiceLibrary(libraries_path)
# return message
message = ""
# add all elements to the PySpice circuit
for element in circuit_lab:
if element == "V":
for dc_voltage_source in circuit_lab["V"]:
circuit.V(
dc_voltage_source["id"],
circuit.gnd if dc_voltage_source["node1"] == "gnd" else
dc_voltage_source["node1"],
circuit.gnd if dc_voltage_source["node2"] == "gnd" else
dc_voltage_source["node2"],
dc_voltage_source["value"] @ u_V)
elif element == "VA":
for ac_voltage_source in circuit_lab["VA"]:
circuit.SinusoidalVoltageSource(
ac_voltage_source["id"],
circuit.gnd if ac_voltage_source["node1"] == "gnd" else
ac_voltage_source["node1"],
circuit.gnd if ac_voltage_source["node2"] == "gnd" else
ac_voltage_source["node2"],
amplitude=ac_voltage_source["amplitude"] @ u_V,
frequency=ac_voltage_source["frequency"] @ u_Hz,
offset=ac_voltage_source["offset"] @ u_V)
elif element == "I":
for dc_current_source in circuit_lab["I"]:
circuit.I(
dc_current_source["id"],
circuit.gnd if dc_current_source["node1"] == "gnd" else
dc_current_source["node1"],
circuit.gnd if dc_current_source["node2"] == "gnd" else
dc_current_source["node2"],
dc_current_source["value"] @ u_A)
elif element == "IA":
for ac_current_source in circuit_lab["IA"]:
circuit.SinusoidalCurrentSource(
ac_current_source["id"],
circuit.gnd if ac_current_source["node1"] == "gnd" else
ac_current_source["node1"],
circuit.gnd if ac_current_source["node2"] == "gnd" else
ac_current_source["node2"],
amplitude=ac_current_source["amplitude"] @ u_A,
frequency=ac_current_source["frequency"] @ u_Hz,
offset=ac_current_source["offset"] @ u_A)
elif element == "R":
for resistor in circuit_lab["R"]:
circuit.R(
resistor["id"], circuit.gnd if resistor["node1"]
== "gnd" else resistor["node1"], circuit.gnd
if resistor["node2"] == "gnd" else resistor["node2"],
resistor["value"] @ u_Ω)
elif element == "L":
for inductor in circuit_lab["L"]:
circuit.L(
inductor["id"], circuit.gnd if inductor["node1"]
== "gnd" else inductor["node1"], circuit.gnd
if inductor["node2"] == "gnd" else inductor["node2"],
inductor["value"] @ u_H)
elif element == "C":
for capacitor in circuit_lab["C"]:
circuit.C(
capacitor["id"], circuit.gnd if capacitor["node1"]
== "gnd" else capacitor["node1"], circuit.gnd
if capacitor["node2"] == "gnd" else capacitor["node2"],
capacitor["value"] @ u_F)
elif element == "D":
for diode in circuit_lab["D"]:
try:
circuit.include(spice_library[diode["modelType"]])
circuit.X(
diode["id"], diode["modelType"], circuit.gnd
if diode["node1"] == "gnd" else diode["node1"],
circuit.gnd
if diode["node2"] == "gnd" else diode["node2"])
except KeyError as e:
message += " " + str(e)
elif element == "nBJT":
for nBJT in circuit_lab["nBJT"]:
try:
circuit.include(spice_library[nBJT["modelType"]])
circuit.BJT(nBJT["id"],
circuit.gnd if nBJT["node1"] == "gnd" else
nBJT["node1"],
circuit.gnd if nBJT["node2"] == "gnd" else
nBJT["node2"],
circuit.gnd if nBJT["node3"] == "gnd" else
nBJT["node3"],
model=nBJT["modelType"])
except KeyError as e:
message += " " + str(e)
elif element == "pBJT":
for pBJT in circuit_lab["pBJT"]:
try:
circuit.include(spice_library[pBJT["modelType"]])
circuit.BJT(pBJT["id"],
circuit.gnd if pBJT["node3"] == "gnd" else
pBJT["node3"],
circuit.gnd if pBJT["node2"] == "gnd" else
pBJT["node2"],
circuit.gnd if pBJT["node1"] == "gnd" else
pBJT["node1"],
model=pBJT["modelType"])
except KeyError as e:
message += " " + str(e)
elif element == "NMOS":
for NMOS in circuit_lab["NMOS"]:
try:
circuit.include(spice_library[NMOS["modelType"]])
# nodes are: drain, gate, source, bulk
circuit.MOSFET(NMOS["id"],
circuit.gnd if NMOS["node4"] == "gnd"
else NMOS["node4"],
circuit.gnd if NMOS["node2"] == "gnd"
else NMOS["node2"],
circuit.gnd if NMOS["node3"] == "gnd"
else NMOS["node3"],
circuit.gnd if NMOS["node1"] == "gnd"
else NMOS["node1"],
model=NMOS["modelType"])
except KeyError as e:
message += " " + str(e)
elif element == "PMOS":
for PMOS in circuit_lab["PMOS"]:
try:
circuit.include(spice_library[PMOS["modelType"]])
# nodes are: source, gate, drain, bulk
circuit.MOSFET(PMOS["id"],
circuit.gnd if PMOS["node1"] == "gnd"
else PMOS["node1"],
circuit.gnd if PMOS["node2"] == "gnd"
else PMOS["node2"],
circuit.gnd if PMOS["node3"] == "gnd"
else PMOS["node3"],
circuit.gnd if PMOS["node4"] == "gnd"
else PMOS["node4"],
model=PMOS["modelType"])
except KeyError as e:
message += " " + str(e)
# add ammeter as a 0 volt voltage source
elif element == "AM":
for ammeter in circuit_lab["AM"]:
circuit.V(
ammeter["id"], circuit.gnd if ammeter["node1"] == "gnd"
else ammeter["node1"], circuit.gnd if ammeter["node2"]
== "gnd" else ammeter["node2"], ammeter["value"] @ u_V)
if not message:
self.spice = circuit
return message
return "Undefined model type:" + message
