def _getphasors(freq, cv):
"""Return transfer functions for a given frequency."""
s = 2 * np.pi * freq * 1j
Zc = par(cv['Rc'], 1./(cv['Cc'] * s))
Ze = par(cv['Re'], 1./(cv['Ce'] * s))
Z = cv['R'] + 1./(cv['C'] * s)
Zb = cv['hie'] + Ze*(1 + cv['hfe'])
Rb = cv['Rb']
hfe = cv['hfe']
ib_vin = 1./(Z + par(Zb, Rb)) * Rb /(Zb + Rb)
vu_vin = - Zc * hfe * ib_vin # A(f) actually
ic_vin = hfe * ib_vin
vce_vin = -(Ze*(hfe + 1) + Zc*hfe) * ib_vin
return vce_vin, ic_vin, ib_vin, vu_vin
def _solve_circuit(self):
"""Solve circuit, adding keys to cv dictionary."""
cv = self.cv
bv = eledp.bjt.get_transistor(cv['Q'])
cv['Vbb'] = Vbb = (cv['R2'] * 1./(cv['R1']+ cv['R2'])) * cv['Vcc']
cv['Rb'] = Rb = par(cv['R1'], cv['R2'])
cv['IcQ'] = IcQ = (Vbb - bv['Vg']) * 1./cv['Re']
cv['VceQ'] = VceQ = cv['Vcc'] - (cv['Rc'] + cv['Re'])*IcQ
cv['IbQ'], cv['hfe'], cv['hie'] = IbQ, hfe, hie = \
eledp.bjt.get_cp(VceQ, IcQ, cv['Q'])
if IbQ < 0: # IbQ > 0
print 'a'
self._valid = False
return
if VceQ < bv['Vces']: # VceQ > Vces
print 'b'
self._valid = False
return
if 50 * Rb*IbQ > Vbb: # Rb * IbQ << Vbb
print 'c'
self._valid = False
return
if 50 * IbQ > IcQ: # IcQ >> IbQ
print 'd'
self._valid = False
return
cv['Rc_o'] = cv['R'] + par(Rb, hie + cv['Re']*(1 + hfe))
cv['Rce_o'] = par(cv['Re'], (Rb + hie)*1./(1 + hfe))
cv['Rce_c'] = par(cv['Re'], (par(Rb, cv['R']) + hie) * 1./(1 + hfe))
cv['Rc_ce'] = cv['R'] + par(Rb, hie)
cv['Rcc_o'] = cv['Rc']
a1 = cv['C']*cv['Rc_o'] + cv['Ce']*cv['Rce_o']
a2 = cv['C'] * cv['Ce'] * cv['Rce_o'] * cv['Rc_ce']
b1 = cv['Cc'] * cv['Rcc_o']
cv['fp1'] = - 1./(2*np.pi) * (-a1 - (a1**2 - 4*a2)**0.5) / (2*a2)
cv['fp2'] = - 1./(2*np.pi) * (-a1 + (a1**2 - 4*a2)**0.5) / (2*a2)
cv['fp3'] = 1./(2 * np.pi * cv['Cc'] * cv['Rcc_o'])
cv['fz'] = 1./(2 * np.pi * cv['Re'] * cv['Ce'])
# fp3 >> fp1,fp2,fz ovvero separazione in banda
if 100 * cv['fp1'] > cv['fp3']:
print 'e'
self._valid = False
return
if 100 * cv['fp2'] > cv['fp3']:
print 'f'
self._valid = False
return
if 100 * cv['fz'] > cv['fp3']:
print 'g'
self._valid = False
return
cv['Acb'] = - cv['Rc'] * hfe * (1./(1 + hie*1./Rb)) * \
1./(par(hie, Rb) + cv['R'])
cv['fcap'] = - cv['fp1'] * cv['fp2'] * 1./cv['fz'] / cv['Acb']
cv['fmin'] = min(cv['fp1'], cv['fp2'], cv['fp3'], cv['fz']) * 10**-2
cv['fmax'] = max(cv['fp1'], cv['fp2'], cv['fp3'], cv['fz']) * 10**2
cv['tfnum']= [-1./(4 * np.pi**2 * cv['fcap'] * cv['fz']),
-1./(2 * np.pi * cv['fcap']), 0]
cv['tfden']=[b1* a2, a2 + a1*b1, a1 + b1, 1]
cv['VuQ'] = cv['Vcc'] - cv['Rc']*cv['IcQ']
def pf(i):
"""On purpose function. See ahead"""
pd = {'R': r'$\Omega$', 'C': 'F', 'V': 'V', 'I': 'A'}
c = pd[i[0]] if i[0] in pd.keys() else ''
return c
cl = []
cl.append('Q: ' + cv['Q'] + '\n')
for i in sorted(CVSTD.keys(), reverse=True):
if i != 'Q':
cl.append(i+ ' = ' + nf(cv[i]) + pf(i) + '\n')
cv['par_txt'] = ''.join(cl)
cv['freqs_txt'] = \
r'$f_z\,=\,' + ('%.4g' % cv['fz']) + 'Hz$\n' + \
r'$f_{p1}\,=\,' + ('%.4g' % cv['fp1']) + 'Hz$\n' + \
r'$f_{p2}\,=\,' + ('%.4g' % cv['fp2']) + 'Hz$\n' + \
r'$f_{p3}\,=\,' + ('%.4g' % cv['fp3']) + 'Hz$\n' + \
r'$\hat{f}\,=\,' + ('%.4g' % cv['fcap']) + 'Hz$'