Is there a common name for this [voltage-boosting] circuit topology/idea?

I've seen "bootstrapping" used in a few more books/articles for this technique:

• Small Signal Audio Design, 2nd ed., by Douglas Self pp. 136-137; shows both an opamp-based boostrap and a BJT-based one. EDIT to add: As it turns out, there some free excerpts from the first edition of the book published in EE Times; the relevant circuits [aimed at JFET input C/V tweaking] are published in an article called "Op amps in small-signal audio design - Part 2: Distortion in bipolar and JFET input op-amps. Rail bootstrapping to reduce CM distortion".

• Analog-to-Digital Conversion, 2nd ed., by Marcel J.M. Pelgrom, pp. 210-211 uses "boostrapping" for an NMOS transistor operating above the rails. There are more CMOS books that use this term for the same purpose, e.g. Uyemura's CMOS Logic Circuit Design p. 319.

• "Advanced techniques tackle advanced op amps' extremely low distortion" by J. Graeme, also reproduced in The EDN Designer's Companion, Here p. 213 the bootstrap is done for measurement purposes.

So I guess that clinches "(rail/[power-]supply) bootstrapping" as a relatively common name for this, even though not every source utters it when discussing such circuits... And the purpose of the rail bootstrap may not always be a voltage swing increase.

If someone finds another (relatively common) term, please contribute another answer.

EDIT: As interesting titbids (found thanks to a rather vague mention on a forum), I found two UK patents on this idea:

• "Zero input capacitance amplifier" (1988) by Bernard / ABI Systems ; uses the 3-opamp version. Title is self-explanatory.
• "Interface circuits" (1980) by Mohapatra / Sandman. Rather uninformative title, if you ask me; shows several variants, some with two BJTs and some with opamps all-around. The stated goal is to increase input impedance and CMRR.

Neither of these UK patents uses the term "bootstrap" though... as far as I can tell, anyway; old UK patents are not OCR'd, so search doesn't work in those PDFs.

There's also an output voltage boost circuit based on this idea in Linear appnote 67 in the article titled Extending Op Amp Supplies to Get More Output Voltage by Dale Eagar (starts on p. 58 in this long document). This one uses MOSFETs on the opamp rails. But it never uses the term "bootstrap". So yeah, "bootstrap" is a common enough term for this, but not universally used... The preferred term at Linear for this circuit idea is extended supply mode, which (if you google it) is found exclusively in their documents... so this alternative term appears to have less traction across the industry as whole.

IMO "bootstrapping" is not an appropriate term for this circuit configuration. "Bootstrapping" means "following"... or to insert a following (opposing) voltage source in series to the input voltage source and a resistor (this old circuit technique is based on one of the Miller theorem applications).

Here (roughly speaking), the op-amp supply voltage varies nonlinearly from 50 V to almost 100 V when the op-amp output voltage changes from 0 V to 100 V (i.e., it is not following). I think the only purpose of this dynamic power supply (50 - 100 V) is to decrease the power dissipated in the op-amp output transistors versus the conventional constant power supply (100 V here).

This idea resembles the variable power supplies with a switchable secondary winding.