Extended output voltage of Op Amp

There is a clever solution in the book "Halbleiter-Schaltungstechnik" by Ulrich Tietze and Christoph Schenk (ISBN 9783540151340) about how to use a general-purpose operational amplifier for larger signals than the amplifier's maximum supply voltage (VCC-VEE or VDD-VSS). The schematic is shown below.

The supply rails follow the amplifier's output voltage, keeping them in the safe operating range?similar to the diagram below.

The operation can easily be confirmed by simulation. The schematic of the simulated circuit is shown below.

, and the waveforms

Let's see what happens when we use this solution for higher gain configuration. The first example is a non-inverting amplifier circuit with a gain of 10. The schematic is shown below.

The waveforms do not look promising.

Let's see how it works the inverting amplifier circuit with a gain of 10. The schematic is shown below.

But the waveforms are not better.

As seen from the simulation, this solution is unsuitable for achieving gain from the circuit. The reason is straightforward. The input voltages must always be between the supply rail's voltages for general-purpose operational amplifiers. When the input voltage goes above or below the range defined by the supply voltages, the circuit will not work properly, or it can be damaged in the worst case. Furthermore, the inputs' common-mode voltage must also be in the input common-mode voltage range, usually less than the input voltage range, for normal operation. In the unity gain configuration, the input voltages equal the output voltage. Thus, it will not cause a problem. But, the input voltages easily fall out of the operating condition at a higher gain because the supply voltages float around the output voltage.

Although it looks like a simple cost-saving solution, it requires a careful analog circuit design, and success is not guaranteed in any application. Using a high-voltage operational amplifier or designing a final stage from discrete components is a much safer solution.