1.8V supervisor for low-voltage rails
The ROHM BU4818G-TR is a single-channel voltage supervisor that monitors a 1.8V supply rail and asserts a reset signal when the voltage drops below that threshold. It is built for designs that need a clean, reliable power-on reset for low-voltage cores — think 1.8V MCU I/O banks, DDR memory termination rails, or the digital supply of a mixed-signal ASIC. The open-drain output can be configured for either active-high or active-low reset polarity, which gives the layout engineer flexibility to match the reset input of the downstream device without an extra inverter gate. Pull the output up to the monitored rail or to a separate 3.3V supply — the open-drain structure handles it.
125°C rating — fits under-hood and industrial gear
The wide temperature range also gives thermal margin in a sealed enclosure — the supervisor keeps working even if the board runs hot.
SOT-753 — field-swappable without hot air
The 5-SSOP package (SOT-753 footprint) is a standard five-pin small-outline package with 0.95 mm pitch. It is large enough to hand-solder with a fine-tip iron — no hot-air station needed for a field swap. The pinout is simple: VDD, GND, and the open-drain output. Orientation is obvious from the pin-1 mark, so a technician can replace it on site with a steady hand and a magnifier.
That means you can qualify it for a new design without worrying about an end-of-life notice mid-production.