Code ported from the DELSIG toolbox by R. Schreier (pydsm.delsig)

Key functions

synthesizeNTF([order, osr, opt, H_inf, f0])

Synthesizes an NTF for a DS modulator by Schreier’s approach.

clans([order, osr, nq, rmax, opt])

Synthesize the NTF for a ΔΣM w/ multibit quantizer by the CLANS method.

synthesizeChebyshevNTF([order, osr, opt, …])

Synthesize the NTF for a DS modulator by a Chebyshev function.

simulateDSM(u, arg2[, nlev, x0, store_xn, …])

Computes the output of a general delta-sigma modulator.

Other selected functions

Delta sigma utilities

partitionABCD(ABCD[, m])

Partition ABCD ss description in A, B, C, D for an m-input sytem

rmsGain(H, f1, f2[, N])

Compute the root-mean-square gain of a DT transfer function.

General utilities

dbv(x)

Converts a voltage (or current) ratio to dB.

dbp(x)

Converts a power ratio to dB.

undbv(x)

Converts argument from db to a voltage ratio.

undbp(x)

Converts argument from db to a power ratio.

dbm(v[, R])

Converts argument from rms voltage to dBm.

undbm(x[, R])

Converts argument from dBm power to rms voltage.

rms(x[, no_dc])

Compute root means square value (RMS) of a vector.

Graphing

plotPZ(H[, color, markersize, showlist])

Plots the poles and zeros of a transfer function.

axisLabels(points, incr)

Generate alphanumeric axis labels.

Plumbing

ds_synNTFobj1(x, p, osr, f0)

Objective function for synthesizeNTF.

ds_f1f2([osr, f0, complex_flag])

Lower and higher extremes of the signal band as normalized frequencies

ds_optzeros(n[, opt])

Zeros which minimize the in-band noise of a delta-sigma modulator

dsclansNTF(x, order, rmax, Hz)

Convert CLANS parameters into an NTF in ZPK form

padl(x, n[, val])

Pad a matrix or a vector on the left.

padr(x, n[, val])

Pad a matrix or a vector x on the right.

padt(x, n[, val])

Pad a matrix or a vector on the top.

padb(x, n[, val])

Pad a matrix or a vector on the bottom.

evalTF(tf, x)

Evaluates a transfer function.

evalRPoly(roots, x[, k])

Compute the value of a polynomial that is given in terms of its roots.