4.35V threshold supervisor in TO-92-3
The DS1811-10+ is a single-channel voltage supervisor from the EconoReset series, monitoring a 4.35V threshold with an active-low, open-drain output. The 100ms minimum reset timeout holds the downstream MCU in reset long enough for the supply to stabilise after a brownout or power-up — a common requirement for Cortex-M and other processors that need a clean reset edge before the boot ROM starts. Housed in the through-hole TO-92-3 package (TO-226AA), it drops into legacy socketed designs or prototype boards without a reflow step.
Open-drain output and reset timing
The open-drain output lets the DS1811-10+ share a common reset line with other peripherals — a pull-up resistor to the MCU's VDD sets the logic-high level, so the supervisor works with 3.3V or 5V systems without a level translator. The active-low polarity means the output sinks current during a reset condition; the downstream processor sees a guaranteed low until the timeout expires. At 4.35V threshold, this part is intended for 5V nominal rails. The 100ms minimum reset timeout gives the bulk capacitor on the 5V rail enough time to charge past the threshold before the processor starts executing — a 10 µF cap on a 100 mA load takes roughly 0.5 ms to rise from 0 to 4.35V, leaving 99.5 ms of margin.
Active production, TO-92-3 footprint
Analog Devices lists the DS1811-10+ as Active. The TO-92-3 package is a standard 0.100-inch pitch, 0.200-inch row spacing — the same footprint used by legacy 78L05 regulators and temperature sensors, so the PCB layout is already familiar to any rework tech or prototype builder. ROHS3 compliant, no special handling needed for lead-free assembly.