What this inverting buck regulator does on your rail
The MAX17577ATC+ is a Himalaya-series inverting buck regulator from Analog Devices that takes a positive input rail from 4.5V to 24V and produces a regulated negative output adjustable from -0.9V down to -36V, delivering up to 1A. It uses a buck topology with synchronous rectification, so the external Schottky diode normally required for inverting converters is eliminated — the internal low-side FET handles the catch function, which keeps the layout tighter and the BOM count lower.
The 1A output rating is the continuous current the regulator can deliver at the negative output rail — enough to bias an op-amp supply, a small LCD bias rail, or a sensor front-end that needs a clean -5V or -12V from a positive-only input. Input range spans 4.5V to 24V, so it runs from a standard 5V, 12V, or 24V industrial supply without a pre-regulator; the output can be set as low as -0.9V or as deep as -36V, covering the common negative rails for analog signal chains and IGBT gate-drive bias. Switching frequency is programmable from 400 kHz to 2.2 MHz — a higher frequency shrinks the inductor and output capacitor but increases switching losses; the 400 kHz end suits designs prioritising efficiency, while 2.2 MHz keeps the magnetics small for space-constrained boards. The output configuration is negative and adjustable, meaning the feedback network sets the exact negative voltage — the part does not produce a positive output, so it is a dedicated inverting solution, not a generic buck that can be wired as Cuk or SEPIC.