90 kHz GBW, 8.6 µA — the power-conscious signal chain choice
The ROHM BU7271SG-TR is a single-channel general-purpose CMOS op-amp that trades bandwidth for extreme low-power operation. Its 90 kHz gain-bandwidth product and 0.05 V/µs slew rate place it firmly in the low-frequency signal conditioning role — think battery monitors, thermistor interfaces, photodiode amplifiers, and always-on sensor buffers where every microamp counts. The 8.6 µA supply current is the headline draw: at that level the part can run continuously from a coin cell without dominating the sleep budget. Rail-to-rail output preserves dynamic range at low supply voltages, and the 1.8 V minimum supply lets it operate directly from a single lithium cell or two alkaline cells.
SOT-753 footprint — fits the tight board, but watch the thermal
The BU7271SG-TR comes in the 5-pin SOT-753 package, also called SC-74A, with the supplier device package listed as 5-SSOP. This is the same footprint as the industry-standard SOT-23-5, so it drops onto existing pads without a layout change. The 8 mA output current per channel is modest — enough to drive a reference input or a low-power ADC, but not a heavy load. At 8.6 µA supply, self-heating is negligible, so the small package is not a thermal constraint in normal operation. Surface-mount assembly is standard; no exposed pad to worry about.