Active production — two-rail supervisor in SOT-23-8
The MAX6391KA46+T is an active-production multi-voltage supervisor from Analog Devices, monitoring two supply rails with a fixed 4.63 V threshold on one channel and an adjustable threshold on the second. The active-low reset output is open drain, pulling low for 140 ms (minimum, adjustable) when either monitored voltage drops below its threshold — a standard sequencing fit for MPU, FPGA, or DSP core and I/O rails.
Threshold selection and reset timing
One channel has a factory-set 4.63 V threshold, typically used for a 5 V nominal rail; the second channel accepts an external resistor divider for any voltage down to 0.6 V. The 140 ms reset timeout is the default minimum; an external capacitor extends it, giving the designer control over power-good hold-off time during start-up sequencing.
SOT-23-8 package and sourcing
Housed in an SOT-23-8 package (supplier device package SOT-23-8), the MAX6391KA46+T is surface-mount and available in tape-and-reel or cut-tape quantities.