Dual-rail supervisor in a six-pin SOT
The BD48HW0G-CTR is a dual-channel voltage detector from ROHM Semiconductor, part of their automotive AEC-Q100 qualified series. It monitors two independent supply rails, each with a 1.277 V threshold, and asserts an open-drain or open-collector output when either rail drops below that level. The reset timeout is 17 µs typical — fast enough to catch a brown-out glitch before the downstream logic enters an undefined state, but not so short that it triggers on supply noise. The -40 to 125 °C operating range covers the under-hood automotive temperature band, making it suitable for engine control units, transmission controllers, and body electronics that see 105 °C on a summer grade.
Housed in a SOT-23-6 package (also designated 6-SSOP), the BD48HW0G-CTR occupies about 3 mm × 3 mm of board area. The six-pin footprint routes cleanly on a two-layer board — no thermal pad or exposed paddle to worry about. Surface-mount assembly with standard reflow profile; the package is compatible with both cut-tape and reel quantities. The open-drain output requires an external pull-up resistor to the monitored rail or to the logic supply. Choose the resistor value to balance rise time against quiescent current — a 10 kΩ pull-up to 3.3 V draws 330 µA when the output is low, which is fine for most automotive loads but may need adjustment for ultra-low-power sleep modes.