My Inquiry
My Account
STMicroelectronics STM809TWX6F
- Part No.:
- STM809TWX6F
- Manufacturer:
- STMicroelectronics
- Category:
- Supervisors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
STM809TWX6F.pdf
- Description:
- IC SUPERVISOR 1 CHANNEL SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:2,450
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
STM809TWX6F from STMicroelectronics is an industrial-grade, active-low microprocessor reset circuit in SOT23-3 package, monitoring 3.0 V supply with ±50 mV threshold accuracy over –40 °C to +85 °C, delivering 140 ms minimum reset pulse width and consuming only 6 µA typical supply current. It ensures reliable MCU reset assertion during brownout events in embedded control, power management, and industrial instrumentation systems.
For engineers reviewing the STM809TWX6F datasheet, STM809TWX6F pinout, STM809TWX6F application, or STM809TWX6F equivalent, key selection criteria include guaranteed RST assertion down to VCC = 1.0 V, push-pull output drive capability (±20 mA), immunity to sub-20 µs/100 mV VCC transients, and compatibility with 3.0 V logic domains requiring precise reset timing.
Technical Context
The STM809TWX6F implements a precision voltage comparator with hysteresis-free threshold detection at 3.08 V (typ) and internal debounce logic that guarantees a minimum 140 ms reset pulse after VCC recovery. Its reset timer (trec) is temperature-compensated, varying only ±10 ms across –40 °C to +85 °C.
No manual reset input (MR) is present - this is a dedicated active-low reset monitor (per Table 1), distinct from STM811/812 variants. The push-pull RST output remains valid down to VCC = 1.0 V and transitions cleanly without external pull-up components.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reset Threshold | 3.08 V (typ), 3.00–3.15 V (min/max over temp) - precisely matches 3.0 V supply rails with margin for ripple and drift. |
| Reset Pulse Width (trec) | 140–280 ms - ensures full MCU initialization before release, exceeding ARM Cortex-M and legacy 8-bit MCU requirements. |
| Supply Current (ICC) | 6 µA (typ) at VCC < 3.6 V - enables battery-backed or ultra-low-power always-on monitoring without measurable drain. |
| VCC Operating Range | 1.2–5.5 V - supports operation during deep brownout and allows use with 1.8 V auxiliary supplies for supervision logic. |
| RST Output Drive | Push-pull, ±20 mA - directly drives MCU reset pins without external buffers or pull resistors in standard 3.0 V systems. |
| Temperature Range | –40 °C to +85 °C - qualified for industrial environments including factory automation and outdoor metering. |
| VCC Transient Immunity | 20 µs max duration at 100 mV overdrive - rejects common switching noise without false resets. |
Pinout & Package
SOT23-3 package: compact 2.9 mm × 2.4 mm surface-mount outline with gull-wing leads, lead-free (ECOPACK®), suitable for high-density PCB layouts and reflow assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (VCC) | Supply Input | Monitored power rail input; internally decoupled - requires local 0.1 µF ceramic capacitor per layout guidelines. |
| 2 (GND) | Ground Reference | Common return for comparator and output stage; must be low-impedance connection to system ground plane. |
| 3 (RST) | Active-Low Reset Output | Push-pull CMOS output asserted low during reset; sinks 1.2 mA at 0.3 V (VCC = VRST min), compatible with TTL/CMOS inputs. |
Key Features
| Feature | Design Value |
|---|---|
| Precision 3.0 V monitoring | 3.08 V threshold with ±50 mV tolerance over full industrial temperature range - eliminates need for external resistor dividers. |
| Guaranteed reset assertion to 1.0 V | RST remains functional down to VCC = 1.0 V - ensures fail-safe reset even during severe undervoltage conditions. |
| No external components required | Self-contained reset generator with internal timer and comparator - reduces BOM count and layout area vs. RC-based solutions. |
| Low-noise transient rejection | Immune to 100 mV VCC glitches ≤20 µs - prevents spurious resets in noisy switch-mode power supply environments. |
| Lead-free SOT23-3 packaging | RoHS-compliant, JEDEC-standard footprint - enables drop-in replacement and automated assembly without process changes. |
Applications
| Industrial PLC I/O Modules | Smart Energy Meters |
|---|---|
|
Use Scenario: Power supply monitoring during grid voltage sags and EMI-rich factory floor operation. IC Role / Device Role / Timing Role: Active-low reset supervisor asserting MCU reset until 3.0 V rail stabilizes post-brownout. Use Value: Prevents firmware corruption by guaranteeing ≥140 ms reset hold time, meeting IEC 61000-4-11 immunity requirements. |
Use Scenario: Long-term battery-backed operation with intermittent AC mains coupling and RF interference. IC Role / Device Role / Timing Role: Low-current (6 µA) reset monitor maintaining supervision during 10-year meter lifetime. Use Value: Eliminates external reset IC leakage paths, preserving backup battery charge while ensuring deterministic boot on power restoration. |
| Medical Diagnostic Handhelds | Automotive Body Control Modules (Non-AEC-Q100) |
|
Use Scenario: Portable ultrasound or glucose monitors powered by single-cell Li-ion with wide VCC swing (3.0–4.2 V). IC Role / Device Role / Timing Role: 3.08 V threshold supervisor enabling safe reset during discharge below 3.2 V cutoff. Use Value: Matches battery voltage profile without recalibration; push-pull RST avoids weak-pull dependencies in space-constrained designs. |
Use Scenario: Aftermarket lighting controllers operating from vehicle battery (9–16 V) with local 3.3 V LDO regulation. IC Role / Device Role / Timing Role: Supervises 3.0 V logic domain of microcontroller, rejecting load-dump transients via 20 µs immunity window. Use Value: Reduces system-level reset failures by 92% compared to RC-based circuits in vibration-prone mounting environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar reset supervision applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX809TRD3T | 3.0 V threshold, same SOT23-3, but 140 ms trec not guaranteed below –20 °C; ICC = 8 µA typ. | Lacks full industrial temp validation; less stable over temperature drift (±100 ppm/°C vs. STM809's 45 ppm/°C). | Acceptable for commercial-temp designs where cost is primary; avoid for extended temperature deployments. |
| TPS3808G30DBVR | 3.0 V threshold, SOT23-6, adjustable delay (200 ms default), ICC = 1.1 µA - lower power but larger footprint. | Requires external capacitor for delay tuning; no MR pin, but higher integration margin for future scalability. | Preferred when ultra-low ICC (<2 µA) is mandatory and board space permits 6-pin variant. |
Compared with MAX809TRD3T and TPS3808G30DBVR, the STM809TWX6F delivers tighter threshold stability (±50 mV vs. ±100 mV), guaranteed trec performance across –40 °C to +85 °C, and optimal footprint efficiency for cost-sensitive industrial designs.
Availability
STM809TWX6F is available at Aetrix Electronics and suitable for industrial PLC I/O modules, smart energy meters, medical handheld diagnostics, and automotive body control modules requiring stable component supply with long lifecycle assurance.
Supply support for STM809TWX6F includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, MCU, power, and sensing solutions for industrial, automotive, and consumer markets.
The STM809 series belongs to ST's precision supervisory IC product line, engineered specifically for robust, low-power reset generation in harsh industrial environments where reliability under voltage stress is non-negotiable.
FAQ
What is the exact reset threshold voltage for STM809TWX6F?
The STM809TWX6F has a nominal reset threshold of 3.08 V at 25 °C, with a guaranteed range of 3.00 V to 3.15 V across –40 °C to +85 °C. This corresponds to the "T" grade in ST's ordering scheme and is validated per Table 5 of Doc ID 9873 Rev 5.
Does STM809TWX6F support manual reset functionality?
No - STM809TWX6F lacks a manual reset (MR) input. It is a dedicated active-low reset monitor (see Table 1). Manual reset capability is only available in STM811/812 variants (SOT143-4 package), which include pin 4 (MR) and dual RST outputs.
Can STM809TWX6F operate reliably below 3.0 V supply?
Yes - it guarantees RST assertion down to VCC = 1.0 V (per Section 2.1), and operates across 1.2–5.5 V. However, reset threshold accuracy degrades below 2.5 V, and the device is specified for 3.0 V system supervision - not sub-2.5 V logic domains.
Is an external pull-up resistor required on the RST pin?
No - the RST pin is push-pull, not open-drain. It actively drives high and low without external components. A pull-up is only needed if RST must remain valid below VCC = 1.0 V (Section 2.4 recommends 100 kΩ to VCC for such edge cases).
STM809TWX6F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Simple Reset/Power-On Reset
- Number of Voltages Monitored:
- 1
- Voltage - Threshold:
- 3.08V
- Output:
- Push-Pull, Totem Pole
- Reset:
- Active Low
- Reset Timeout:
- 140ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
STM809TWX6F FAQ
1.How can I place an order for STM809TWX6F through Aetrix?
Please submit a Request for Quotation (RFQ) for STM809TWX6F on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for STM809TWX6F reliable?
The price and inventory of STM809TWX6F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STM809TWX6F is usually 5 days.
3.What payment methods are accepted for STM809TWX6F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STM809TWX6F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for STM809TWX6F?
STM809TWX6F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your STM809TWX6F order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for STM809TWX6F?
For technical support, including STM809TWX6F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STM809TWX6F requirements.
6.How does Aetrix verify that STM809TWX6F is sourced from the original manufacturer or authorized distributors?
All STM809TWX6F products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that STM809TWX6F meets industry standards.
7.What is the process for return or replacement of STM809TWX6F?
All STM809TWX6F units undergo pre-shipment inspection (PSI). If there is an issue with STM809TWX6F, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The STM809TWX6F part is unused and in its original packaging.
Return procedure for STM809TWX6F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
STM809TWX6F Tags
-
MIC826SYMT-TR
Microchip Technology
-
APX803S-31SA-7
Diodes Incorporated
-
APX803L20-29SA-7
Diodes Incorporated
-
TPS3828-33DBVR
Texas Instruments
-
V6340RSP3B+
EM Microelectronic
-
EM6325CXSP5B-2.9+
EM Microelectronic
-
MCP120T-300I/TT
Microchip Technology
-
MCP130T-315I/TT
Microchip Technology
-
MCP120T-475I/TT
Microchip Technology
-
MCP111T-300E/TT
Microchip Technology
-
MCP120T-315I/TT
Microchip Technology
-
MCP809T-315I/TT
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
