If you take a close look at my PIC based signal multiplier, it becomes apparent how easily that same design can be used for multiple DC analog (0-5)V signal manipulations, logic, and transforms. The chip consists of two protected DC analog (0-5)V signal inputs, and one PPTC protected DC analog output (0.4-4.6)V which is determined in the microprocessor programming by the duty cycle of the PWM output. Because the output is put through a power op-amp follower, the output signal has some decent power behind it. Thus, by modifying the PIC program, the device has a much wider range of possible uses that would otherwise require complicated and component intensive circuits to implement.
So the next time you’re thinking of building an analog circuit with 3+ opamps, you might consider this little guy, instead. You can contact me for a custom solution at https://hintsofozone.net/