Device models for many of our ICs are available in the file thatcorp.lib This library contains SPICE macro models for the following products:
THAT4301 VCA and OA3 op-amp
THAT4301 RMS detector
THAT4301 OA1 Op-amp
THAT4301 OA2 Op-amp
|THAT2252 RMS Detector
THAT1240 Line Receiver
THAT1243 Line Receiver
THAT1246 Line Receiver
THAT1200 InGenius Line Receiver
THAT1203 InGenius Line Receiver
THAT1206 InGenius Line Receiver
THAT300 Series NPN transistor
THAT300 Series PNP transistor
The macro models model typical noise, offset voltage, bias current, gain bandwidth, VCA distortion and other important parameters necessary for SPICE simulation.
Some important notes:
One cannot accurately simulate dynamic gain control while performing an .AC analysis. This is because SPICE is performing a small signal analysis on the devices based on how they are biased after the DC bias portion of the simulation. Large signal behavior, such as the exponential relationship between VBE and IC are not modeled, and this exponential relationship is fundamental to the operation of THAT Corporation's log/anti-log VCAs. Performance with static gain can be simulated with the .AC analysis, and dynamic gain control can be simulated with TRAN (transient) analysis.
Also, the results of .AC analysis with THAT Corporation's RMS detectors can be misleading, since the result only shows the ripple of the RMS detector's log filter, and not the actual DC output. Transient analysis yields the correct DC output, but the user may want to experiment with the .IC statement to speed settling times for the log filter.