def noisesolve(s):
# Calculate the reciprocal G and C matrices
Yreciprocal = G.T + s*C.T
Yreciprocal2, uu = (tk.toMatrix(A) for A in (Yreciprocal, u))
## Calculate transimpedances from currents in each nodes to output
zm = tk.linearsolver(Yreciprocal2, -uu)
xn2out = tk.dot(tk.dot(zm.reshape(1, tk.size(zm)), CY), tk.conj(zm))
## Etract gain
gain = None
if isinstance(self.inputsrc, VS):
gain = self.cir.extract_i(zm,
instjoin(self.inputsrc_name, 'plus'),
refnode=refnode,
refnode_removed=True)
elif isinstance(self.inputsrc, IS):
plus_node = instjoin(self.inputsrc_name, 'plus')
minus_node = instjoin(self.inputsrc_name, 'minus')
gain = self.cir.extract_v(zm,
self.cir.get_node(plus_node),
self.cir.get_node(minus_node),
refnode=refnode, refnode_removed=True)
return xn2out[0], gain
def solve(self, freqs, refnode=gnd, complexfreq = False, u = None):
G, C, CY, u, x, ss = self.dc_steady_state(freqs, refnode,
complexfreq = complexfreq, u = u)
tk = self.toolkit
def noisesolve(s):
# Calculate the reciprocal G and C matrices
Yreciprocal = G.T + s*C.T
Yreciprocal2, uu = (tk.toMatrix(A) for A in (Yreciprocal, u))
## Calculate transimpedances from currents in each nodes to output
zm = tk.linearsolver(Yreciprocal2, -uu)
xn2out = tk.dot(tk.dot(zm.reshape(1, tk.size(zm)), CY), tk.conj(zm))
## Etract gain
gain = None
if isinstance(self.inputsrc, VS):
gain = self.cir.extract_i(zm,
instjoin(self.inputsrc_name, 'plus'),
refnode=refnode,
refnode_removed=True)
elif isinstance(self.inputsrc, IS):
plus_node = instjoin(self.inputsrc_name, 'plus')
minus_node = instjoin(self.inputsrc_name, 'minus')
gain = self.cir.extract_v(zm,
self.cir.get_node(plus_node),
self.cir.get_node(minus_node),
refnode=refnode, refnode_removed=True)
return xn2out[0], gain
# Calculate output voltage noise
if self.outputnodes != None:
ioutp, ioutn = (self.cir.get_node_index(node)
for node in self.outputnodes)
u[ioutp] = -1
u[ioutn] = 1
# Calculate output current noise
else:
plus_term = instjoin(self.outputsrc_name, 'plus')
branch = self.cir.get_terminal_branch(plus_term)[0]
ibranch = self.cir.get_branch_index(branch)
u[ibranch] = -1
## Refer the voltages to the gnd node by removing
## the rows and columns that corresponds to this node
irefnode = self.cir.nodes.index(refnode)
G,C,CY,u = remove_row_col((G,C,CY,u), irefnode, tk)
xn2out, gain = self.noise_map_function(noisesolve, ss, refnode)
# Store results
result = InternalResultDict()
if self.outputnodes != None:
result['Svnout'] = xn2out
elif self.outputsrc != None:
result['Sinout'] = xn2out
# Calculate the gain from the input voltage source by using the
# transimpedance vector to find the transfer from the branch voltage of
# the input source to the output
if isinstance(self.inputsrc, VS):
result['gain'] = gain
result['Svninp'] = xn2out / abs(gain)**2
elif isinstance(self.inputsrc, IS):
result['gain'] = gain
result['Sininp'] = xn2out / abs(gain)**2
return result
