Demonstrating one channel of the V2164 quad VCA using a spice model developed for EasyEDA by signality.co.uk
AFTER PLACING V2164D.5: CHANGE NAME TO V2164_bias
Simulatable Spice Symbols for the V2164 VCA
- Models developed by signality.co.uk. 200521
- This is a purely behavioural model and its use is subject to the following limitations.
- The quoted gain constant and temperature coefficient are accurately modelled.
- Exponential Control Voltage Law: The adherence of the gain vs. control voltage to an exponential law may be slightly more accurate at the extremes of control range compared to the real device.
- Frequency Response and Instability: There is insufficient information in the datasheets for any of the various versions of the 2164 type VGA - original SSM or Analog Devices versions of the SSM2164, the CoolAudio V2164 or the re-engineered SSI2164 from Sound Semiconductor - from which to accurately model the frequency response vs. gain and therefore to model the exact behaviour of the instability which the input RC compensation network is required to stabilise.
- This model has a best guess attempt at modelling a frequency response which results in instability at gains of 0dB and which the recommended input RC compensation network does indeed stabilise.
- THD and Noise: Not currently modelled.
- Input bias and output offset currents: Not currently modelled.
- Control voltage feedthrough: Not currently modelled.
- Power Supply Rejection Ratio (PSRR): Not currently modelled.
- How to use the models: The V2164_amp blocks simulate and can be used separately. To model the power supply drain of a complete V2164 device including the MODE current, the V2164_bias block must be placed in the simulation.
Note however that the MODE current fed into the V2164_bias block has no effect on the THD or the noise performance of the V2164_amp model.