The Analog Switch Matrix is a complex router, allowing one input to be switched between four outputs, or vice versa, or even to route one signal through one of four external effects (e.g. wave multipliers, filters etc.). It can also be used as four independent analog switches.
All analog switches are independently addressed, so combinations of these arrangements are also possible. Further enhancing this is that the common input and output external are to the main switching matrix. There is also a separate mixer than can be used for recombining signals when routing between different effects, or the mixer can be used as an independent general purpose DC coupled unity gain mixer.
The analog switch is DC coupled so can be used for both control voltages and audio signals.
Suitable drivers for one-at-a-time switch control include the Gate Sequencer and the Weighted Random Switch. Any module, or combination of modules, that generates gate signals can be used to drive the matrix if having more than one switch closed at time is acceptable or desirable.
The Weighted Random Switch is a companion module, as it can be directly connected while leaving the standard gate inputs functional.
A little on how it works:
The schematic of the Analog Switch Matrix.
How does a device (the 4066) that has only a 15v range allow at least +/-10V to pass through it? The answer is it doesn't. By powering the 4066 and its associated drive circuitry from +14.4V and -0.6V, and placing the output of the analog switch at the virtual ground point of an inverting op-amp buffer, the full range of the signal is allowed to pass while the voltage at that point is held near or at 0V by the action of the op-amp while the analog switch is closed. When the analog switch is open, the diode connected between the input and 0V prevents in incoming signal from going below -0.6V, and thus prevents it from going outside the allowed input range. There is no need to protect against excursions in the positive direction, as these are in the allowed input range. A second diode at the output of the analog switch prevents the op-amp from driving the output below -0.6V, should the switch open while such potential exists.
|Brand||Cat Girl Synth (CGS)|
|Additional Resources||BOM & More Information|