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for complex systems like sigma-delta modulator, simulation starts with system level (block level) with ideal blocks like gain and switches, for finding some block specs like op amp gain. usually system level sim. is done in matlab/simulink; simulink is simpler but slower but matlab codes are much faster-speed is essential for parameter sweeping for optimum design.
after finding some block specs it is possible to use more accurate models like switch resistance, clock overlaps, opamp bandwidth and slew rate in the same environment i.e. matlab/simulink.
if system level is successful, with the block specs known, u can design each block (like opamp and comparators) seprately with spice and in transistor level, finally using this blocks u can simulate all of the modulator.
NOTE: Before full transistor level sim. usually a semi-transistor level simulation is necessary with some blocks(opamp and cmparator) in transistor level and others like switches and clocks in system level i.e. ideal switches and pulse voltage source as clocks; this simulation is done in spice.
Consider also to use excel to simulate the time discrete behaviour of the SigmaDelta. The 2 dimensional presentation and that you can look at all internal states gives you very good feedback. Limit cycles, startup, all the ugly stuff of SigmaDelta could be seen there. Limitation is the 65k FFT in excel.
as I know , many analog design use C for delta_sigma modulator
and someone use matlab(simulink) design delta_sigma recently..
but it is idea case condition ..
and I know a tool called "smash " dolphin provide a mix mode simulation
maybe sometime we can use mix mode tool simulation whole chip
because deltaSigma AD need
1. frontend --> deltaSigma modulator , comparator ...
2. backend --> digital filter like SinC filter or guass filter
+ IIR/FIR by verilog code
complete deltaSigma ADC need mix mode tool for whole chip design
hi can you please help me with the second order sigma delta modulators in hspice ... need to code it in hspice to simulate it in synopsis.. can u send me more schematics if u have please.... which u have tried or .. so.. please in need of it urgently..