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STMicroelectronics STM812MW16F
- Part No.:
- STM812MW16F
- Manufacturer:
- STMicroelectronics
- Category:
- Supervisors
- Package:
- TO-253-4, TO-253AA
- Datasheet:
-
STM812MW16F.pdf
- Description:
- IC SUPERVISOR 1 CHANNEL SOT143-4
- Quantity:
- Payment:
- Shipping:
Inventory:2,330
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Product details
Overview
STM812MW16F from STMicroelectronics is an industrial-grade active-high reset supervisor IC in SOT143-4 package, monitoring 3.3 V supply (VRST = 4.25–4.50 V), delivering 140–280 ms reset pulse width, with 6 µA typical supply current and guaranteed RST assertion down to VCC = 1.0 V. It supports manual reset via MR input and is used in microcontroller-based embedded systems requiring reliable power-on and brownout reset.
For engineers reviewing the STM812MW16F datasheet, STM812MW16F pinout, STM812MW16F application, or STM812MW16F equivalent, key selection criteria include reset threshold tolerance (±25 mV at 25 °C), MR input pull-up resistance (10–30 kΩ), trec temperature stability (±10 ms over –40 to +85 °C), and compatibility with 3.3 V MCU I/O logic levels.
Technical Context
The STM812MW16F implements a precision voltage comparator with hysteresis to monitor VCC against a trimmed bandgap reference, triggering a monostable timer that generates a minimum 140 ms active-high RST pulse upon undervoltage or MR assertion. Its internal debounce logic rejects MR glitches <100 ns and ensures clean reset assertion even during fast VCC transients.
It features dual-output capability (RST and RST) and operates across full industrial temperature range (–40 °C to +85 °C) with VRST temperature coefficient of 45 ppm/°C. The MR input includes a 20 kΩ internal pull-up resistor, enabling direct push-button connection without external components.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reset Threshold (VRST) | 4.25–4.50 V at –40 to +85 °C - precisely monitors 3.3 V supply rails with ±25 mV tolerance at 25 °C |
| Reset Pulse Width (trec) | 140–280 ms - ensures sufficient MCU initialization time after power-up or brownout recovery |
| Supply Current (ICC) | 6 µA typ at VCC < 3.6 V - enables ultra-low-power operation in battery-backed or energy-sensitive systems |
| MR Input Pull-up | 10–30 kΩ - allows direct push-button-to-GND interface with no external resistor required |
| VCC Operating Range | 1.0–5.5 V - guarantees valid RST output down to 1.0 V, supporting deep brownout detection |
| Output Drive | RST sinks 1.2 mA (VCC = VRST min) - directly drives standard CMOS/TTL reset inputs without buffering |
| Temperature Range | –40 °C to +85 °C - qualified for industrial environments including factory automation and motor control |
Pinout & Package
SOT143-4 (W1) package: 4-pin, surface-mount, lead-free, small-outline transistor outline with 1.92 mm lead pitch and 2.80 × 2.10 mm body size.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VCC | Supply input | Power rail input monitored by internal voltage comparator; must be decoupled with 0.1 µF capacitor |
| VSS | Ground reference | Return path for all internal circuitry and output sink current; requires low-impedance PCB connection |
| RST | Active-high reset output | Push-pull CMOS output asserted high during reset; sinks 1.2 mA at VRST(min); valid down to VCC = 1.0 V |
| MR | Manual reset input | Active-low input with 20 kΩ internal pull-up; asserts RST when pulled low; immune to <100 ns noise glitches |
Key Features
| Feature | Design Value |
|---|---|
| Precision 3.3 V supply monitoring | VRST = 4.25–4.50 V with 45 ppm/°C drift - matches 3.3 V system margin requirements while maintaining accuracy over temperature |
| Guaranteed reset assertion at low VCC | RST remains valid down to VCC = 1.0 V - ensures deterministic reset behavior during deep brownout conditions |
| Integrated MR debounce | No external RC network needed - internal logic rejects sub-100 ns glitches, simplifying board layout and BOM |
| Low quiescent current | 6 µA typical ICC - extends battery life in always-on supervisory applications such as smart sensors and IoT edge nodes |
| Industrial temperature qualification | –40 °C to +85 °C operation - validated for use in harsh environments including PLCs, industrial gateways, and motor drives |
Applications
| Industrial PLC Controller | Smart Energy Meter |
|---|---|
Use Scenario: Power cycling and brownout events in factory-floor programmable logic controllers. IC Role / Device Role / Timing Role: Supervisory reset generator asserting active-high RST to ARM Cortex-M3/M4 MCU on VCC drop below 4.25 V or MR button press. Use Value: Prevents firmware corruption during unstable mains supply by enforcing ≥140 ms reset hold time and rejecting transient-induced false resets. |
Use Scenario: Long-term deployment in utility-grade electricity meters exposed to grid fluctuations and temperature extremes. IC Role / Device Role / Timing Role: Primary reset supervisor for metering SoC, monitoring 3.3 V LDO output and providing MR access for field calibration reset. Use Value: Ensures reliable boot sequence under wide VCC variation (1.0–5.5 V) and maintains reset validity down to 1.0 V during capacitor discharge. |
| Motor Drive Control Board | Medical Diagnostic Handheld |
Use Scenario: High-noise environment with switching power supplies and PWM-driven inverters. IC Role / Device Role / Timing Role: Reset source for safety-critical motion controller MCU, with MR tied to emergency stop circuit. Use Value: Immunity to VCC transients ≤20 µs/100 mV eliminates spurious resets caused by EMI coupling into power rails. |
Use Scenario: Portable diagnostic device powered by rechargeable Li-ion battery with variable VCC (3.0–4.2 V). IC Role / Device Role / Timing Role: Brownout detector for low-power ARM-based host processor, using MR for user-initiated self-test reset. Use Value: 6 µA supply current minimizes standby drain; 140 ms trec accommodates slow-start DC-DC converters in battery management path. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar reset supervisor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX809TRD3+T | 4.63 V reset threshold, SOT23-3, no MR input, 140 ms trec | Lacks manual reset function; limited to basic power-on reset only | Select when MR is unnecessary and board space constraints favor 3-pin SOT23 |
| TPS3808G12DBVR | 1.2 V threshold, adjustable via external resistor, 200 ms trec, 1.6 µA ICC | Designed for ultra-low-voltage systems; requires external components for threshold setting | Prefer for battery-powered devices needing sub-2 V supervision and minimal current draw |
Compared with STM812MW16F, MAX809TRD3+T offers smaller footprint but omits MR functionality, while TPS3808G12DBVR achieves lower ICC and adjustable threshold at the cost of added external components and reduced noise immunity on MR.
Availability
STM812MW16F is available at Aetrix Electronics and suitable for industrial automation, smart metering, motor control, and portable medical electronics requiring stable component supply and long-lifecycle support.
Supply support for STM812MW16F 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 STM8xx series is ST's dedicated family of low-power voltage supervisors targeting cost-sensitive, space-constrained embedded systems requiring precise, robust reset generation without software intervention.
FAQ
What is the exact reset threshold voltage range for STM812MW16F?
The STM812MW16F has a guaranteed reset threshold (VRST) of 4.25 V to 4.50 V over the full industrial temperature range (–40 °C to +85 °C), with a typical value of 4.38 V at 25 °C. This range is specifically calibrated for reliable supervision of 3.3 V supply rails with adequate margin against ripple and tolerance stack-up.
Does STM812MW16F require an external pull-up resistor on the MR pin?
No. The MR pin integrates a 20 kΩ internal pull-up resistor (10–30 kΩ over temperature), allowing direct connection of a normally open push-button switch between MR and GND. No external resistor is needed, reducing BOM count and PCB area while maintaining noise immunity up to 100 ns glitches.
Can STM812MW16F drive a standard CMOS reset input directly?
Yes. The RST output is a push-pull CMOS driver capable of sinking 1.2 mA at VCC = VRST(min), which exceeds the input leakage and capacitive load requirements of most microcontrollers (e.g., STM32, PIC, MSP430). It meets standard TTL/CMOS logic thresholds and requires no external buffer or level-shifting circuitry.
How does STM812MW16F behave when VCC drops below 1.0 V?
Below 1.0 V, the RST output ceases to sink current and transitions to a high-impedance state. To maintain a defined logic low during deep brownout, a 100 kΩ pull-up resistor to VCC is recommended per ST's application guidance - ensuring RST remains asserted until VCC fully collapses, preventing unintended MCU wake-up.
STM812MW16F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- TO-253-4, TO-253AA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Simple Reset/Power-On Reset
- Number of Voltages Monitored:
- 1
- Voltage - Threshold:
- 4.38V
- Output:
- Push-Pull, Totem Pole
- Reset:
- Active High
- Reset Timeout:
- 140ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-143-4
STM812MW16F FAQ
1.How can I place an order for STM812MW16F through Aetrix?
Please submit a Request for Quotation (RFQ) for STM812MW16F 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 STM812MW16F reliable?
The price and inventory of STM812MW16F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STM812MW16F is usually 5 days.
3.What payment methods are accepted for STM812MW16F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STM812MW16F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for STM812MW16F?
STM812MW16F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your STM812MW16F 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 STM812MW16F?
For technical support, including STM812MW16F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STM812MW16F requirements.
6.How does Aetrix verify that STM812MW16F is sourced from the original manufacturer or authorized distributors?
All STM812MW16F 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 STM812MW16F meets industry standards.
7.What is the process for return or replacement of STM812MW16F?
All STM812MW16F units undergo pre-shipment inspection (PSI). If there is an issue with STM812MW16F, 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 STM812MW16F part is unused and in its original packaging.
Return procedure for STM812MW16F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
STM812MW16F Tags
-
MIC826SYMT-TR
Microchip Technology
-
APX803S-31SA-7
Diodes Incorporated
-
APX803L20-29SA-7
Diodes Incorporated
-
TPS3828-33DBVR
Texas Instruments
-
V6340RSP3B+
EM Microelectronic
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EM6325CXSP5B-2.9+
EM Microelectronic
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MCP120T-300I/TT
Microchip Technology
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MCP130T-315I/TT
Microchip Technology
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MCP120T-475I/TT
Microchip Technology
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MCP111T-300E/TT
Microchip Technology
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MCP120T-315I/TT
Microchip Technology
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MCP809T-315I/TT
Microchip Technology
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