Skip to main content
Log in
STMicroelectronics STM809TWX6F — Microcontrollers & Processors (MCU / MPU / DSP)

STM809TWX6F Simple Reset/Power-On Reset, 3.08V Threshold

MPNSTM809TWX6F
End of Life

STMicroelectronics STM809TWX6F, Simple Reset/Power-On Reset, Active Low, Push-Pull Output, 3.08V Threshold, 140ms Minimum Reset Timeout, SOT-23-3, -40°C to 85°C.

$0.58Ref. price · indicative, final on quote
STMicroelectronics STM809TWX6F datasheet (PDF)
PackagingTO-236-3, SC-59, SOT-23-3
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

STM809TWX6F specifications
ParameterValue
TypeSimple Reset/Power-On Reset
MountingSurface Mount
Voltage - threshold3.08V
Number of voltages monitored1
Operating temperature-40°C ~ 85°C (TA)
ResetActive Low
OutputPush-Pull, Totem Pole
PackageTape & Reel (TR); Cut Tape (CT)
Reset timeout140ms Minimum
CaseTO-236-3, SC-59, SOT-23-3

Product details

The STM809TWX6F is a simple reset / power-on reset supervisor IC from STMicroelectronics. It monitors a single 3.08 V supply rail and asserts an active-low reset output — push-pull, no external pull-up needed — for a minimum of 140 ms when the voltage drops below threshold. The SOT-23-3 package and surface-mount footprint let it drop into compact board layouts alongside microcontrollers, FPGAs, or other voltage-sensitive logic.

140 ms timeout — sizing for power-up sequencing

The minimum 140 ms reset pulse width covers the power-on ramp of most bulk capacitors and switching regulators.

Frequently asked questions

Is STM809TWX6F compatible with 3.3V systems?

Yes, the 3.08 V threshold is designed for 3.3 V logic rails. It asserts reset before the supply drops below the minimum operating voltage of typical 3.3 V MCUs and FPGAs, providing adequate brown-out protection without false triggering on normal ripple.

What is the pinout of STM809TWX6F?

The STM809TWX6F comes in a SOT-23-3 package (also known as TO-236-3 or SC-59). The pinout is standard for this supervisor family: GND, RESET (active-low output), and VCC. Refer to the STM809 datasheet for the exact pin numbering.

What are the equivalent parts to STM809TWX6F?

A close functional equivalent within the ST portfolio is the STM706M6F, which also offers an active-low reset, push-pull output, and 140 ms minimum timeout in a similar SOT-23 package. The STM706PM6F provides an active-high reset instead. For an open-drain output variant, the STM1061N29WX6F is an alternative, though its threshold differs at 2.9 V.