def __init__(self, instanceName):
cir.Element.__init__(self, instanceName)
# Use junctions to model diodes and capacitors
self.jif = SVJunction()
self.jir = SVJunction()
self.jile = Junction()
self.jilc = Junction()
# collector/emitter terminal numbers: may be re-mapped by
# extrinsic device
self._ct = 0
self._et = 2
def __init__(self, instanceName):
cir.Element.__init__(self, instanceName)
# Use junctions to model diodes and capacitors
self.jif = SVJunction()
self.jir = SVJunction()
self.jile = Junction()
self.jilc = Junction()
# collector/emitter terminal numbers: may be re-mapped by
# extrinsic device
self._ct = 0
self._et = 2
class SVBJTi(cir.Element):
"""
State-variable-based Gummel-Poon intrinsic BJT model based
This implementation based mainly on previous implementation in
carrot and some equations from Pspice manual, with the addition of
the state-variable definitions.
Terminal order: 0 Collector, 1 Base, 2 Emitter, (3 Bulk, not included)::
C (0) o----, 4----o E (2)
\ /
\ /
---------
|
o
B (1)
Can be used for NPN or PNP transistors.
Intrinsic Internal Topology
+++++++++++++++++++++++++++
The state variable formulation is achieved by replacing the BE and
BC diodes (Ibf, Ibr) with state-variable based diodes. This
requires two additional variables (nodes) but eliminates large
positive exponentials from the model::
Term : x2
+--------------------------+
| |
/|\ /^\
( | ) gyr v2 ( | ) gyr vbc(x)
\V/ \|/
tref | |
,----+--------------------------+
| | |
| /^\ /|\
| ( | ) gyr v1 ( | ) gyr vbe(x)
--- \|/ \V/
V | |
+--------------------------+
Term : x1
All currents/charges in the model are functions of voltages v3
(x2) and v4 (x1). Note that vbc and vbe are now also functions of
x1, x2.
In addition we may need 2 additional nodes (plus reference) if rb
is not zero: Bi for the internal base node and tib to measure the
internal base current and calculate Rb(ib).
1. If RB == 0::
+----------------+--o 0 (C)
- | |
/^\ |
v2 ( | ) ibc(x2) |
\|/ |
+ | /|\
(B) 1 o---------+ ( | ) ice(x1,x2)
+ | \V/
/|\ |
v1 ( | ) ibe(x1) |
\V/ |
- | |
+----------------+--o 2 (E)
2. If RB != 0::
+----------------+--o 0 (C)
- | |
/^\ |
gyr tib v2 ( | ) ibc(x2) |
\|/ |
,---, + | /|\
(B) 1 o----( --> )----------+ Term : Bi ( | ) ice(x1,x2)
`---` + | \V/
/|\ |
v1 ( | ) ibe(x1) |
\V/ |
- | |
gyr v(1,Bi) +----------------+--o 2 (E)
,---,
+---( <-- ) -----+
| `---` |
tref | | ib/gyr
,--+ |
| | ,---, | Term : ib
| +---( --> )------+
| `---`
---
V gyr ib Rb(ib)
Charge sources are connected between internal nodes defined
above. If xcjc is not 1 but RB is zero, xcjc is ignored.
"""
devType = "svbjt"
paramDict = dict(
cir.Element.tempItem,
type = ('Type (npn or pnp)', '', str, 'npn'),
isat = ('Transport saturation current', 'A', float, 1e-16),
bf = ('Ideal maximum forward beta', '', float, 100.),
nf = ('Forward current emission coefficient', '', float, 1.),
vaf = ('Forward early voltage', 'V', float, 0.),
ikf = ('Forward-beta high current roll-off knee current', 'A',
float, 0.),
ise = ('Base-emitter leakage saturation current', 'A', float, 0.),
ne = ('Base-emitter leakage emission coefficient', '', float, 1.5),
br = ('Ideal maximum reverse beta', '', float, 1.),
nr = ('Reverse current emission coefficient', '', float, 1.),
var = ('Reverse early voltage', 'V', float, 0.),
ikr = ('Corner for reverse-beta high current roll off', 'A', float, 0.),
isc = ('Base collector leakage saturation current', 'A', float, 0.),
nc = ('Base-collector leakage emission coefficient', '', float, 2.),
rb = ('Zero bias base resistance', 'Ohm', float, 0.),
rbm = ('Minimum base resistance', 'Ohm', float, 0.),
irb = ('Current at which rb falls to half of rbm', 'A', float, 0.),
eg = ('Badgap voltage', 'eV', float, 1.11),
cje = ('Base emitter zero bias p-n capacitance', 'F', float, 0.),
vje = ('Base emitter built in potential', 'V', float, 0.75),
mje = ('Base emitter p-n grading factor', '', float, 0.33),
cjc = ('Base collector zero bias p-n capacitance', 'F', float, 0.),
vjc = ('Base collector built in potential', 'V', float, 0.75),
mjc = ('Base collector p-n grading factor', '', float, 0.33),
xcjc = ('Fraction of cbc connected internal to rb', '', float, 1.),
fc = ('Forward bias depletion capacitor coefficient', '', float, 0.5),
tf = ('Ideal forward transit time', 's', float, 0.),
xtf = ('Transit time bias dependence coefficient', '', float, 0.),
vtf = ('Transit time dependency on vbc', 'V', float, 0.),
itf = ('Transit time dependency on ic', 'A', float, 0.),
tr = ('Ideal reverse transit time', 's', float, 0.),
xtb = ('Forward and reverse beta temperature coefficient', '',
float, 0.),
xti = ('IS temperature effect exponent', '', float, 3.),
tnom = ('Nominal temperature', 'C', float, 27.),
area = ('Current multiplier', '', float, 1.)
)
def __init__(self, instanceName):
cir.Element.__init__(self, instanceName)
# Use junctions to model diodes and capacitors
self.jif = SVJunction()
self.jir = SVJunction()
self.jile = Junction()
self.jilc = Junction()
# collector/emitter terminal numbers: may be re-mapped by
# extrinsic device
self._ct = 0
self._et = 2
def process_params(self):
"""
Adjusts internal topology and makes preliminary calculations
according to parameters.
"""
# Define topology first. Add state variable nodes
x2 = self.add_internal_term('x2','s.v.')
x1 = self.add_internal_term('x1','s.v.')
tref = self.add_reference_term()
# Default configuration assumes rb == 0
# ibe, vbe, ibc, vbc, ice
self.csOutPorts = [(1, self._et), (tref, x1), (1, self._ct),
(tref, x2), (self._ct, self._et)]
# Controling voltages are x1, x2
self.controlPorts = [(x1, tref), (x2, tref)]
# qbe, qbc
self.qsOutPorts = [(1, self._et), (1, self._ct)]
# Flag to signal if the extra charge Qbx is needed or not
self._qbx = False
# Default state-variable VCCSs
self.linearVCCS = [((1, self._et), (x1, tref), glVar.gyr),
((1, self._ct), (x2, tref), glVar.gyr)]
if self.rb != 0.:
# rb is not zero: add internal terminals
tBi = self.add_internal_term('Bi', 'V')
tib = self.add_internal_term('ib', '{0} A'.format(glVar.gyr))
# Add Linear VCCS for gyrator(s)
self.linearVCCS = [((tBi, self._et), (x1, tref), glVar.gyr),
((tBi, 0), (x2, tref), glVar.gyr),
((1, tBi), (tib, tref), glVar.gyr),
((tib, tref), (1, tBi), glVar.gyr)]
# ibe, vbe, ibc, vbc, ice, Rb(ib) * ib
self.csOutPorts = [(tBi, self._et), (tref, x1), (tBi, self._ct),
(tref, x2), (self._ct, self._et), (tref, tib)]
# Controling voltages are x1, x2 and gyrator port
self.controlPorts = [(x1, tref), (x2, tref), (tib, tref)]
# qbie, qbic
self.qsOutPorts = [(tBi, self._et), (tBi, self._ct)]
# Now check if Cjbc must be splitted (since rb != 0)
if (self.cjc != 0.) and (self.xcjc < 1.):
# add extra charge source
self.qsOutPorts.append((1, self._ct))
self._qbx = True
# Make sure the guess is consistent
self.vPortGuess = np.zeros(len(self.controlPorts))
# # Try guess in active region
# self.vPortGuess[0] = 100. # x1
# self.vPortGuess[1] = -1. # x2
# if self.rb != 0.:
# self.vPortGuess[2] = 1e-6 / glVar.gyr # ib
# In principle we may not need any charge
keepPorts = [ ]
if self.cje + self.tf != 0.:
# keep qbe
keepPorts.append(self.qsOutPorts[0])
if self.cjc + self.tr != 0.:
# keep qbc, qbx (if any)
if self._qbx:
keepPorts += self.qsOutPorts[-2:]
else:
keepPorts.append(self.qsOutPorts[-1])
self.qsOutPorts = keepPorts
# keep track of how many output variables are needed
self.ncurrents = len(self.csOutPorts)
self.ncharges = len(self.qsOutPorts)
# NPN or PNP
if self.type == 'pnp':
self._typef = -1.
else:
self._typef = 1.
# Calculate common variables
# Absolute nominal temperature
self.Tnomabs = self.tnom + const.T0
self.egapn = self.eg - .000702 * (self.Tnomabs**2) \
/ (self.Tnomabs + 1108.)
# jif produces if, cje
self.jif.process_params(self.isat, self.nf, self.fc, self.cje,
self.vje, self.mje, self.xti, self.eg,
self.Tnomabs)
# jir produces ir, cjc
self.jir.process_params(self.isat, self.nr, self.fc, self.cjc,
self.vjc, self.mjc, self.xti, self.eg,
self.Tnomabs)
if self.ise != 0.:
# jile produces ile
self.jile.process_params(self.ise, self.ne, 0, 0, 0, 0,
self.xti, self.eg, self.Tnomabs)
if self.isc != 0.:
# jilc produces ilc
self.jilc.process_params(self.isc, self.nc, 0, 0, 0, 0,
self.xti, self.eg, self.Tnomabs)
# Constants needed for rb(ib) calculation
if self.irb != 0.:
self._ck1 = 144. / self.irb / self.area /np.pi/np.pi
self._ck2 = np.pi*np.pi * np.sqrt(self.irb * self.area) / 24.
def set_temp_vars(self, temp):
"""
Calculate temperature-dependent variables, given temp in deg. C
"""
# Absolute temperature (note self.temp is in deg. C)
self.Tabs = const.T0 + temp
# Normalized temp
self.tnratio = self.Tabs / self.Tnomabs
tnXTB = pow(self.tnratio, self.xtb)
# Thermal voltage
self.vt = const.k * self.Tabs / const.q
# Temperature-adjusted egap
self.egap_t = self.eg - .000702 * (self.Tabs**2) / (self.Tabs + 1108.)
# set temperature in juctions
self.jif.set_temp_vars(self.Tabs, self.Tnomabs, self.vt,
self.egapn, self.egap_t)
self.jir.set_temp_vars(self.Tabs, self.Tnomabs, self.vt,
self.egapn, self.egap_t)
# Adjust ise and isc (which have different temperature variation)
if self.ise != 0.:
self.jile.set_temp_vars(self.Tabs, self.Tnomabs, self.vt,
self.egapn, self.egap_t)
self.jile._t_is /= tnXTB
if self.isc != 0.:
self.jilc.set_temp_vars(self.Tabs, self.Tnomabs, self.vt,
self.egapn, self.egap_t)
self.jilc._t_is /= tnXTB
# Now some BJT-only variables
self._bf_t = self.bf * tnXTB
self._br_t = self.br * tnXTB
def eval_cqs(self, vPort):
"""
Calculates currents/charges
Input is a vector may be one of the following, depending on
parameter values::
vPort = [xbe, xbc]
vPort = [xbe, xbc, v4_i] (gyrator voltage, irb != 0)
Output also depends on parameter values. Charges only present
if parameters make them different than 0 (i.e., cje, tf, cjc,
etc. are set to nonzero values)::
iVec = [ibe, vbe, ibc, vbc, ice]
iVec = [ibe, vbe, ibc, vbc, ice, gyr*ib*Rb] (rb != 0)
qVec = [qbe, qbc]
qVec = [qbe, qbc, qbx] (rb != 0 and cjc != 1)
"""
# Invert state variables if needed
vPort1 = self._typef * vPort
# Calculate junctions currents and voltages
(ibf, vbe) = self.jif.get_idvd(vPort1[0])
(ibr, vbc) = self.jir.get_idvd(vPort1[1])
if self.ise != 0.:
ile = self.jile.get_id(vbe)
else:
ile = 0.
if self.isc != 0.:
ilc = self.jilc.get_id(vbc)
else:
ilc = 0.
# Kqb
q1m1 = 1.
if self.var != 0.:
q1m1 -= vbe / self.var
if self.vaf != 0.:
q1m1 -= vbc / self.vaf
kqb = 1. / q1m1
# We need extra checking to consider the following
# possibilities to create the AD tape:
#
# 1. both ikf and ikr are zero -> no tape generated
# 2. One of them is nonzero but both ibf and ibr are zero -> want tape
# but only for the nonzero parameter
if self.ikf + self.ikr != 0.:
q2 = 0.
if self.ikf != 0.:
q2 += ibf / self.ikf
if self.ikr != 0.:
q2 += ibr / self.ikr
kqb *= .5 * (1. + np.sqrt(1. + 4. * q2))
# Create output vector [ibe, ibc, ice, ...]
iVec = np.zeros(self.ncurrents, dtype = type(ibf))
qVec = np.zeros(self.ncharges, dtype = type(ibf))
# ibe, vbe
iVec[0] = ibf / self._bf_t + ile
iVec[1] = glVar.gyr * vbe
# ibc, vbc
iVec[2] = ibr / self._br_t + ilc
iVec[3] = glVar.gyr * vbc
# ice
iVec[4] = (ibf - ibr) / kqb
# RB
if self.rb != 0.:
# Using gyrator
# vPort1[2] not defined if rb == 0
# ib has area effect included (removed by _ck1 and _ck2)
ib = vPort1[2] * glVar.gyr
if self.irb != 0.:
ib1 = np.abs(ib)
x = np.sqrt(1. + self._ck1 * ib1) - 1.
x *= self._ck2 / np.sqrt(ib1)
tx = np.tan(x)
c = self.rbm + 3. * (self.rb - self.rbm) \
* (tx - x) / (x * tx * tx)
rb = ad.condassign(ib1, c, self.rb)
else:
rb = self.rbm + (self.rb - self.rbm) / kqb
# Output is gyr * ib * rb. It is divided by area^2 to
# compensate that the whole vector is multiplied by area
# at the end
iVec[5] = glVar.gyr * ib * rb / pow(self.area, 2)
vbcx = ib * rb / self.area + vbc
# Charges -----------------------------------------------
# Note that if tf == 0 and cje == 0, nothing is calculated and
# nothing is assigned to the output vector.
# qbe is the first charge (0)
if self.tf != 0.:
# Effective tf
tfeff = self.tf
if self.vtf != 0.:
x = ibf / (ibf + self.itf)
# safe_exp() not needed since positive vbc grows
# logarithmically
tfeff *= (1. + self.xtf * x*x *
np.exp(vbc /1.44 /self.vtf))
qVec[0] = tfeff * ibf
if self.cje != 0.:
qVec[0] += self.jif.get_qd(vbe)
# qbc
if self._qbx:
if self.tr != 0.:
qVec[-2] = self.tr * ibr
if self.cjc != 0.:
qVec[-2] += self.jir.get_qd(vbc) * self.xcjc
# qbx
qVec[-1] = self.jir.get_qd(vbcx) * (1. - self.xcjc)
else:
if self.tr != 0.:
qVec[-1] = self.tr * ibr
if self.cjc != 0.:
qVec[-1] += self.jir.get_qd(vbc)
# Consider area effect and invert currents if needed
iVec *= self.area * self._typef
qVec *= self.area * self._typef
return (iVec, qVec)
def power(self, vPort, currV):
"""
Calculate total instantaneous power
Input: control voltages as in eval_cqs() and currents from
returned by eval_cqs()
"""
# vce = vbe - vbc
gyrvce = currV[1] - currV[3]
if self.rb != 0.:
# currV[5] = ib * Rb * gyr
# vPort[2] = ib / gyr
pRb = currV[5] * vPort[2]
else:
pRb = 0.
# pout = ibe * vbie + ibc * vbic + vce * ice + pRb
pout = (currV[0] * currV[1] + currV[2] * currV[3]
+ currV[4] * gyrvce) / glVar.gyr + pRb
return pout
def get_OP(self, vPort):
"""
Calculates operating point information
Input: same as eval_cqs
Output: dictionary with OP variables
For now it is quite incomplete
"""
# First we need the Jacobian
(outV, jac) = self.eval_and_deriv(vPort)
power = self.power(vPort, outV)
# calculate gm, etc. in terms od jac for state-variable
# formulation
opDict = dict(
VBE = outV[1] / glVar.gyr,
VCE = (outV[1] - outV[3]) / glVar.gyr,
IB = outV[0] + outV[2],
IC = outV[4] - outV[2],
IE = - outV[4] - outV[0],
Temp = self.temp,
Power = power,
)
return opDict
def get_noise(self, f):
"""
Return noise spectral density at frequency f
Requires a previous call to get_OP()
Not implemented yet
"""
return None
class SVBJTi(cir.Element):
"""
State-variable-based Gummel-Poon intrinsic BJT model based
This implementation based mainly on previous implementation in
carrot and some equations from Pspice manual, with the addition of
the state-variable definitions.
Terminal order: 0 Collector, 1 Base, 2 Emitter, (3 Bulk, not included)::
C (0) o----, 4----o E (2)
\ /
\ /
---------
|
o
B (1)
Can be used for NPN or PNP transistors.
Intrinsic Internal Topology
+++++++++++++++++++++++++++
The state variable formulation is achieved by replacing the BE and
BC diodes (Ibf, Ibr) with state-variable based diodes. This
requires two additional variables (nodes) but eliminates large
positive exponentials from the model::
Term : x2
+--------------------------+
| |
/|\ /^\
( | ) gyr v2 ( | ) gyr vbc(x)
\V/ \|/
tref | |
,----+--------------------------+
| | |
| /^\ /|\
| ( | ) gyr v1 ( | ) gyr vbe(x)
--- \|/ \V/
V | |
+--------------------------+
Term : x1
All currents/charges in the model are functions of voltages v3
(x2) and v4 (x1). Note that vbc and vbe are now also functions of
x1, x2.
In addition we may need 2 additional nodes (plus reference) if rb
is not zero: Bi for the internal base node and tib to measure the
internal base current and calculate Rb(ib).
1. If RB == 0::
+----------------+--o 0 (C)
- | |
/^\ |
v2 ( | ) ibc(x2) |
\|/ |
+ | /|\
(B) 1 o---------+ ( | ) ice(x1,x2)
+ | \V/
/|\ |
v1 ( | ) ibe(x1) |
\V/ |
- | |
+----------------+--o 2 (E)
2. If RB != 0::
+----------------+--o 0 (C)
- | |
/^\ |
gyr tib v2 ( | ) ibc(x2) |
\|/ |
,---, + | /|\
(B) 1 o----( --> )----------+ Term : Bi ( | ) ice(x1,x2)
`---` + | \V/
/|\ |
v1 ( | ) ibe(x1) |
\V/ |
- | |
gyr v(1,Bi) +----------------+--o 2 (E)
,---,
+---( <-- ) -----+
| `---` |
tref | | ib/gyr
,--+ |
| | ,---, | Term : ib
| +---( --> )------+
| `---`
---
V gyr ib Rb(ib)
Charge sources are connected between internal nodes defined
above. If xcjc is not 1 but RB is zero, xcjc is ignored.
"""
devType = "svbjt"
paramDict = dict(
cir.Element.tempItem,
type=('Type (npn or pnp)', '', str, 'npn'),
isat=('Transport saturation current', 'A', float, 1e-16),
bf=('Ideal maximum forward beta', '', float, 100.),
nf=('Forward current emission coefficient', '', float, 1.),
vaf=('Forward early voltage', 'V', float, 0.),
ikf=('Forward-beta high current roll-off knee current', 'A', float,
0.),
ise=('Base-emitter leakage saturation current', 'A', float, 0.),
ne=('Base-emitter leakage emission coefficient', '', float, 1.5),
br=('Ideal maximum reverse beta', '', float, 1.),
nr=('Reverse current emission coefficient', '', float, 1.),
var=('Reverse early voltage', 'V', float, 0.),
ikr=('Corner for reverse-beta high current roll off', 'A', float, 0.),
isc=('Base collector leakage saturation current', 'A', float, 0.),
nc=('Base-collector leakage emission coefficient', '', float, 2.),
rb=('Zero bias base resistance', 'Ohm', float, 0.),
rbm=('Minimum base resistance', 'Ohm', float, 0.),
irb=('Current at which rb falls to half of rbm', 'A', float, 0.),
eg=('Badgap voltage', 'eV', float, 1.11),
cje=('Base emitter zero bias p-n capacitance', 'F', float, 0.),
vje=('Base emitter built in potential', 'V', float, 0.75),
mje=('Base emitter p-n grading factor', '', float, 0.33),
cjc=('Base collector zero bias p-n capacitance', 'F', float, 0.),
vjc=('Base collector built in potential', 'V', float, 0.75),
mjc=('Base collector p-n grading factor', '', float, 0.33),
xcjc=('Fraction of cbc connected internal to rb', '', float, 1.),
fc=('Forward bias depletion capacitor coefficient', '', float, 0.5),
tf=('Ideal forward transit time', 's', float, 0.),
xtf=('Transit time bias dependence coefficient', '', float, 0.),
vtf=('Transit time dependency on vbc', 'V', float, 0.),
itf=('Transit time dependency on ic', 'A', float, 0.),
tr=('Ideal reverse transit time', 's', float, 0.),
xtb=('Forward and reverse beta temperature coefficient', '', float,
0.),
xti=('IS temperature effect exponent', '', float, 3.),
tnom=('Nominal temperature', 'C', float, 27.),
area=('Current multiplier', '', float, 1.))
def __init__(self, instanceName):
cir.Element.__init__(self, instanceName)
# Use junctions to model diodes and capacitors
self.jif = SVJunction()
self.jir = SVJunction()
self.jile = Junction()
self.jilc = Junction()
# collector/emitter terminal numbers: may be re-mapped by
# extrinsic device
self._ct = 0
self._et = 2
def process_params(self):
"""
Adjusts internal topology and makes preliminary calculations
according to parameters.
"""
# Define topology first. Add state variable nodes
x2 = self.add_internal_term('x2', 's.v.')
x1 = self.add_internal_term('x1', 's.v.')
tref = self.add_reference_term()
# Default configuration assumes rb == 0
# ibe, vbe, ibc, vbc, ice
self.csOutPorts = [(1, self._et), (tref, x1), (1, self._ct),
(tref, x2), (self._ct, self._et)]
# Controling voltages are x1, x2
self.controlPorts = [(x1, tref), (x2, tref)]
# qbe, qbc
self.qsOutPorts = [(1, self._et), (1, self._ct)]
# Flag to signal if the extra charge Qbx is needed or not
self._qbx = False
# Default state-variable VCCSs
self.linearVCCS = [((1, self._et), (x1, tref), glVar.gyr),
((1, self._ct), (x2, tref), glVar.gyr)]
if self.rb != 0.:
# rb is not zero: add internal terminals
tBi = self.add_internal_term('Bi', 'V')
tib = self.add_internal_term('ib', '{0} A'.format(glVar.gyr))
# Add Linear VCCS for gyrator(s)
self.linearVCCS = [((tBi, self._et), (x1, tref), glVar.gyr),
((tBi, 0), (x2, tref), glVar.gyr),
((1, tBi), (tib, tref), glVar.gyr),
((tib, tref), (1, tBi), glVar.gyr)]
# ibe, vbe, ibc, vbc, ice, Rb(ib) * ib
self.csOutPorts = [(tBi, self._et), (tref, x1), (tBi, self._ct),
(tref, x2), (self._ct, self._et), (tref, tib)]
# Controling voltages are x1, x2 and gyrator port
self.controlPorts = [(x1, tref), (x2, tref), (tib, tref)]
# qbie, qbic
self.qsOutPorts = [(tBi, self._et), (tBi, self._ct)]
# Now check if Cjbc must be splitted (since rb != 0)
if (self.cjc != 0.) and (self.xcjc < 1.):
# add extra charge source
self.qsOutPorts.append((1, self._ct))
self._qbx = True
# Make sure the guess is consistent
self.vPortGuess = np.zeros(len(self.controlPorts))
# # Try guess in active region
# self.vPortGuess[0] = 100. # x1
# self.vPortGuess[1] = -1. # x2
# if self.rb != 0.:
# self.vPortGuess[2] = 1e-6 / glVar.gyr # ib
# In principle we may not need any charge
keepPorts = []
if self.cje + self.tf != 0.:
# keep qbe
keepPorts.append(self.qsOutPorts[0])
if self.cjc + self.tr != 0.:
# keep qbc, qbx (if any)
if self._qbx:
keepPorts += self.qsOutPorts[-2:]
else:
keepPorts.append(self.qsOutPorts[-1])
self.qsOutPorts = keepPorts
# keep track of how many output variables are needed
self.ncurrents = len(self.csOutPorts)
self.ncharges = len(self.qsOutPorts)
# NPN or PNP
if self.type == 'pnp':
self._typef = -1.
else:
self._typef = 1.
# Calculate common variables
# Absolute nominal temperature
self.Tnomabs = self.tnom + const.T0
self.egapn = self.eg - .000702 * (self.Tnomabs**2) \
/ (self.Tnomabs + 1108.)
# jif produces if, cje
self.jif.process_params(self.isat, self.nf, self.fc, self.cje,
self.vje, self.mje, self.xti, self.eg,
self.Tnomabs)
# jir produces ir, cjc
self.jir.process_params(self.isat, self.nr, self.fc, self.cjc,
self.vjc, self.mjc, self.xti, self.eg,
self.Tnomabs)
if self.ise != 0.:
# jile produces ile
self.jile.process_params(self.ise, self.ne, 0, 0, 0, 0, self.xti,
self.eg, self.Tnomabs)
if self.isc != 0.:
# jilc produces ilc
self.jilc.process_params(self.isc, self.nc, 0, 0, 0, 0, self.xti,
self.eg, self.Tnomabs)
# Constants needed for rb(ib) calculation
if self.irb != 0.:
self._ck1 = 144. / self.irb / self.area / np.pi / np.pi
self._ck2 = np.pi * np.pi * np.sqrt(self.irb * self.area) / 24.
def set_temp_vars(self, temp):
"""
Calculate temperature-dependent variables, given temp in deg. C
"""
# Absolute temperature (note self.temp is in deg. C)
self.Tabs = const.T0 + temp
# Normalized temp
self.tnratio = self.Tabs / self.Tnomabs
tnXTB = pow(self.tnratio, self.xtb)
# Thermal voltage
self.vt = const.k * self.Tabs / const.q
# Temperature-adjusted egap
self.egap_t = self.eg - .000702 * (self.Tabs**2) / (self.Tabs + 1108.)
# set temperature in juctions
self.jif.set_temp_vars(self.Tabs, self.Tnomabs, self.vt, self.egapn,
self.egap_t)
self.jir.set_temp_vars(self.Tabs, self.Tnomabs, self.vt, self.egapn,
self.egap_t)
# Adjust ise and isc (which have different temperature variation)
if self.ise != 0.:
self.jile.set_temp_vars(self.Tabs, self.Tnomabs, self.vt,
self.egapn, self.egap_t)
self.jile._t_is /= tnXTB
if self.isc != 0.:
self.jilc.set_temp_vars(self.Tabs, self.Tnomabs, self.vt,
self.egapn, self.egap_t)
self.jilc._t_is /= tnXTB
# Now some BJT-only variables
self._bf_t = self.bf * tnXTB
self._br_t = self.br * tnXTB
def eval_cqs(self, vPort):
"""
Calculates currents/charges
Input is a vector may be one of the following, depending on
parameter values::
vPort = [xbe, xbc]
vPort = [xbe, xbc, v4_i] (gyrator voltage, irb != 0)
Output also depends on parameter values. Charges only present
if parameters make them different than 0 (i.e., cje, tf, cjc,
etc. are set to nonzero values)::
iVec = [ibe, vbe, ibc, vbc, ice]
iVec = [ibe, vbe, ibc, vbc, ice, gyr*ib*Rb] (rb != 0)
qVec = [qbe, qbc]
qVec = [qbe, qbc, qbx] (rb != 0 and cjc != 1)
"""
# Invert state variables if needed
vPort1 = self._typef * vPort
# Calculate junctions currents and voltages
(ibf, vbe) = self.jif.get_idvd(vPort1[0])
(ibr, vbc) = self.jir.get_idvd(vPort1[1])
if self.ise != 0.:
ile = self.jile.get_id(vbe)
else:
ile = 0.
if self.isc != 0.:
ilc = self.jilc.get_id(vbc)
else:
ilc = 0.
# Kqb
q1m1 = 1.
if self.var != 0.:
q1m1 -= vbe / self.var
if self.vaf != 0.:
q1m1 -= vbc / self.vaf
kqb = 1. / q1m1
# We need extra checking to consider the following
# possibilities to create the AD tape:
#
# 1. both ikf and ikr are zero -> no tape generated
# 2. One of them is nonzero but both ibf and ibr are zero -> want tape
# but only for the nonzero parameter
if self.ikf + self.ikr != 0.:
q2 = 0.
if self.ikf != 0.:
q2 += ibf / self.ikf
if self.ikr != 0.:
q2 += ibr / self.ikr
kqb *= .5 * (1. + np.sqrt(1. + 4. * q2))
# Create output vector [ibe, ibc, ice, ...]
iVec = np.zeros(self.ncurrents, dtype=type(ibf))
qVec = np.zeros(self.ncharges, dtype=type(ibf))
# ibe, vbe
iVec[0] = ibf / self._bf_t + ile
iVec[1] = glVar.gyr * vbe
# ibc, vbc
iVec[2] = ibr / self._br_t + ilc
iVec[3] = glVar.gyr * vbc
# ice
iVec[4] = (ibf - ibr) / kqb
# RB
if self.rb != 0.:
# Using gyrator
# vPort1[2] not defined if rb == 0
# ib has area effect included (removed by _ck1 and _ck2)
ib = vPort1[2] * glVar.gyr
if self.irb != 0.:
ib1 = np.abs(ib)
x = np.sqrt(1. + self._ck1 * ib1) - 1.
x *= self._ck2 / np.sqrt(ib1)
tx = np.tan(x)
c = self.rbm + 3. * (self.rb - self.rbm) \
* (tx - x) / (x * tx * tx)
rb = ad.condassign(ib1, c, self.rb)
else:
rb = self.rbm + (self.rb - self.rbm) / kqb
# Output is gyr * ib * rb. It is divided by area^2 to
# compensate that the whole vector is multiplied by area
# at the end
iVec[5] = glVar.gyr * ib * rb / pow(self.area, 2)
vbcx = ib * rb / self.area + vbc
# Charges -----------------------------------------------
# Note that if tf == 0 and cje == 0, nothing is calculated and
# nothing is assigned to the output vector.
# qbe is the first charge (0)
if self.tf != 0.:
# Effective tf
tfeff = self.tf
if self.vtf != 0.:
x = ibf / (ibf + self.itf)
# safe_exp() not needed since positive vbc grows
# logarithmically
tfeff *= (1. +
self.xtf * x * x * np.exp(vbc / 1.44 / self.vtf))
qVec[0] = tfeff * ibf
if self.cje != 0.:
qVec[0] += self.jif.get_qd(vbe)
# qbc
if self._qbx:
if self.tr != 0.:
qVec[-2] = self.tr * ibr
if self.cjc != 0.:
qVec[-2] += self.jir.get_qd(vbc) * self.xcjc
# qbx
qVec[-1] = self.jir.get_qd(vbcx) * (1. - self.xcjc)
else:
if self.tr != 0.:
qVec[-1] = self.tr * ibr
if self.cjc != 0.:
qVec[-1] += self.jir.get_qd(vbc)
# Consider area effect and invert currents if needed
iVec *= self.area * self._typef
qVec *= self.area * self._typef
return (iVec, qVec)
def power(self, vPort, currV):
"""
Calculate total instantaneous power
Input: control voltages as in eval_cqs() and currents from
returned by eval_cqs()
"""
# vce = vbe - vbc
gyrvce = currV[1] - currV[3]
if self.rb != 0.:
# currV[5] = ib * Rb * gyr
# vPort[2] = ib / gyr
pRb = currV[5] * vPort[2]
else:
pRb = 0.
# pout = ibe * vbie + ibc * vbic + vce * ice + pRb
pout = (currV[0] * currV[1] + currV[2] * currV[3] +
currV[4] * gyrvce) / glVar.gyr + pRb
return pout
def get_OP(self, vPort):
"""
Calculates operating point information
Input: same as eval_cqs
Output: dictionary with OP variables
For now it is quite incomplete
"""
# First we need the Jacobian
(outV, jac) = self.eval_and_deriv(vPort)
power = self.power(vPort, outV)
# calculate gm, etc. in terms od jac for state-variable
# formulation
opDict = dict(
VBE=outV[1] / glVar.gyr,
VCE=(outV[1] - outV[3]) / glVar.gyr,
IB=outV[0] + outV[2],
IC=outV[4] - outV[2],
IE=-outV[4] - outV[0],
Temp=self.temp,
Power=power,
)
return opDict
def get_noise(self, f):
"""
Return noise spectral density at frequency f
Requires a previous call to get_OP()
Not implemented yet
"""
return None