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STMicroelectronics STM6321MAWY6F
- Part No.:
- STM6321MAWY6F
- Manufacturer:
- STMicroelectronics
- Category:
- Supervisors
- Package:
- SC-74A, SOT-753
- Datasheet:
-
STM6321MAWY6F.pdf
- Description:
- IC SUPERVISOR 1 CHANNEL SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,000
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Product details
Overview
STM6321MAWY6F from STMicroelectronics is a 5-pin precision voltage supervisor IC with integrated watchdog timer and manual reset input, designed for microprocessor reset management in embedded systems. It monitors VCC at 3.3 V (±2.5%), asserts active-low open-drain RST output for 1.4 ms (typ.), features 1.6 s (typ.) watchdog timeout, and operates from –40 to +85 °C with 3 µA supply current - used in industrial PLCs, IoT edge nodes, and battery-powered controllers.
For engineers reviewing the STM6321MAWY6F datasheet, STM6321MAWY6F pinout, STM6321MAWY6F application, or STM6321MAWY6F equivalent, key selection criteria include its open-drain RST output compatibility with multi-rail systems, guaranteed reset assertion down to VCC = 1.0 V, low-power watchdog supervision, and SOT23-5 footprint suitability for space-constrained PCB layouts.
Technical Context
The STM6321MAWY6F implements a precision bandgap reference and comparator to detect VCC drops below 3.3 V threshold (±2.5% over temperature), triggering reset assertion within 10 µs. Its watchdog timer resets on WDI inactivity ≥1.6 s (typ.), cleared by any WDI edge (≥50 ns pulse width supported).
Reset output is active-low open-drain, requiring external pull-up; MR input includes internal 52 kΩ pull-up and accepts TTL/CMOS logic or momentary switch grounding. The device guarantees valid RST assertion down to VCC = 1.0 V across full industrial temperature range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC Threshold | 3.3 V ±2.5% - ensures reliable reset activation for 3.3 V systems under voltage sag or brownout |
| RST Pulse Width | 1.4 ms (typ.) - meets minimum reset hold time requirements of most ARM Cortex-M and RISC-V MCUs |
| Watchdog Timeout | 1.6 s (typ.) - provides sufficient margin to detect firmware lockup without false triggers during normal operation |
| Supply Current | 3 µA (typ.) - enables use in always-on, battery-backed applications with multi-year runtime |
| Operating Temp | –40 to +85 °C - certified for industrial-grade deployment in harsh ambient environments |
| VCC Range | 1.0 to 5.5 V - supports operation during deep brownout and compatibility with 1.8 V–5 V logic domains |
| Reset Output Type | Active-low open-drain - allows wired-OR configuration with other reset sources and level-shifting across voltage domains |
Pinout & Package
STM6321MAWY6F is housed in a standard 5-pin SOT23-5 package (JEDEC MO-178AA), with 1.3 mm height, 2.9 mm × 1.6 mm footprint, and gull-wing leads compatible with automated reflow assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1: WDI | Watchdog input | Edge-sensitive input; toggling within 1.6 s prevents reset; floating or tristated disables watchdog |
| 2: VCC | Power supply | Primary supply rail (1.0–5.5 V); powers internal reference, comparator, and logic |
| 3: RST | Active-low open-drain reset output | Sinks current when asserted; requires external pull-up resistor (e.g., 10 kΩ) to target voltage rail |
| 4: MR | Manual reset input | Active-low input with internal 52 kΩ pull-up; grounded via switch to force reset; tolerant of noise with optional 0.1 µF bypass |
| 5: VSS | Ground | Reference return path for all internal circuits and I/O pins |
Key Features
| Feature | Design Value |
|---|---|
| Precision 3.3 V monitoring | ±2.5% threshold accuracy over –40 to +85 °C ensures consistent brownout detection across temperature |
| Open-drain RST with 1.4 ms pulse | Enables multi-source reset bus sharing and voltage-level translation without level shifters |
| Guaranteed reset down to VCC = 1.0 V | Ensures fail-safe reset assertion even during severe power collapse, critical for non-volatile state preservation |
| Low 3 µA quiescent current | Minimizes battery drain in always-on supervisory roles, supporting >10-year coin-cell operation |
| MR with internal 52 kΩ pull-up | Eliminates external pull-up component; simplifies BOM and reduces PCB area for push-button reset implementation |
Applications
| Industrial PLC Controller | Smart Sensor Node |
|---|---|
Use Scenario: Microcontroller in programmable logic controller experiences firmware hang due to EMI-induced corruption during field operation. IC Role / Device Role / Timing Role: Supervisor asserts open-drain RST to force hardware reset; watchdog timeout (1.6 s) detects unresponsive MCU; MR allows field technician-initiated recovery. Use Value: Prevents system lockup without operator intervention, maintaining deterministic control loop timing and process continuity. |
Use Scenario: Battery-powered environmental sensor node sleeps for minutes between readings, requiring ultra-low-power supervision. IC Role / Device Role / Timing Role: Monitors 3.3 V LDO output; asserts RST if supply dips during RF transmission; 3 µA ICC extends battery life beyond 5 years. Use Value: Eliminates need for MCU-based software reset polling, reducing active duty cycle and enabling true deep-sleep modes. |
| Medical Diagnostic Handheld | Automotive Body Control Module |
Use Scenario: Portable ultrasound device must guarantee safe shutdown and restart after power interruption during imaging session. IC Role / Device Role / Timing Role: Detects VCC drop below 3.3 V threshold; holds RST low for 1.4 ms to meet ARM Cortex-M4 reset spec; MR enables user-triggered recalibration. Use Value: Ensures deterministic boot sequence and data integrity preservation across power cycles, meeting IEC 62304 safety requirements. |
Use Scenario: BCM microcontroller resets unpredictably during load-dump transients on 12 V vehicle bus. IC Role / Device Role / Timing Role: Supervises 3.3 V domain derived from automotive DC-DC converter; open-drain RST interfaces with multiple subsystems sharing same reset net. Use Value: Provides robust reset coordination across CAN, LIN, and GPIO peripherals despite voltage ripple up to ±200 mV. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar voltage supervisor with watchdog applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX6321US33D3+ | 3.3 V threshold (±1.5%), 1.5 s watchdog, SOT23-5, but no MR input - only WDI and RST pins | Lacks manual reset capability; unsuitable where field service reset is required | Select when MR is unnecessary and tighter threshold tolerance is prioritized over reset flexibility |
| TPS3808G33DBVR | 3.3 V threshold (±0.5%), 200 ms reset pulse, push-pull RST, no WDI - watchdog function absent | Provides higher accuracy but omits watchdog; requires external timer circuit for hang detection | Select when watchdog is handled separately and minimal reset pulse jitter is critical for high-speed processors |
Compared with MAX6321US33D3+ and TPS3808G33DBVR, STM6321MAWY6F uniquely combines open-drain RST, MR input, and watchdog in one SOT23-5 package - enabling compact, self-contained reset supervision without external components or secondary timing circuits.
Availability
STM6321MAWY6F is available at Aetrix Electronics and suitable for industrial automation, battery-powered IoT devices, and medical handheld equipment requiring stable component supply and long-term manufacturability.
Supply support for STM6321MAWY6F 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, delivering silicon solutions for automotive, industrial, and consumer markets since 1987.
STM632x belongs to ST's precision power-supervision product line, engineered specifically for reliable microprocessor reset control in resource-constrained, mission-critical embedded systems.
FAQ
What is the exact reset threshold voltage and tolerance for STM6321MAWY6F?
The STM6321MAWY6F has a nominal VCC reset threshold of 3.3 V with ±2.5% tolerance over the full operating temperature range (–40 to +85 °C), verified per STMicroelectronics DocID11110 Rev 14, Table 6. This ensures consistent brownout detection across industrial environments without calibration.
Can the watchdog function be disabled, and how?
Yes - the watchdog timer is disabled when the WDI pin is left floating or driven by a tristate buffer in high-impedance state. ST specifies maximum leakage current ≤10 µA and load capacitance ≤200 pF under this condition, eliminating unintended timeouts without modifying firmware or adding external circuitry.
What pull-up resistor value is recommended for the open-drain RST output?
A 10 kΩ pull-up resistor to the target logic rail (e.g., 3.3 V or 5 V) is recommended and validated in ST's application diagrams (Figure 11). This value ensures logic-low voltage <0.4 V when sinking 2 mA and logic-high voltage >0.8×VCC while accommodating typical MCU input leakage and PCB trace capacitance.
Does STM6321MAWY6F assert reset during power-up, and what is the delay?
Yes - it asserts RST low for a guaranteed minimum reset timeout period (trec) of 1.4 ms (typ.) after VCC rises above 3.3 V. This power-on reset pulse is generated internally and independent of MR or WDI activity, ensuring clean MCU initialization before code execution begins.
STM6321MAWY6F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Simple Reset/Power-On Reset
- Number of Voltages Monitored:
- 1
- Voltage - Threshold:
- 4.39V
- Output:
- Open Drain, Push-Pull
- Reset:
- Active High/Active Low
- Reset Timeout:
- 1ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
STM6321MAWY6F FAQ
1.How can I place an order for STM6321MAWY6F through Aetrix?
Please submit a Request for Quotation (RFQ) for STM6321MAWY6F 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 STM6321MAWY6F reliable?
The price and inventory of STM6321MAWY6F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STM6321MAWY6F is usually 5 days.
3.What payment methods are accepted for STM6321MAWY6F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STM6321MAWY6F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for STM6321MAWY6F?
STM6321MAWY6F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your STM6321MAWY6F 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 STM6321MAWY6F?
For technical support, including STM6321MAWY6F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STM6321MAWY6F requirements.
6.How does Aetrix verify that STM6321MAWY6F is sourced from the original manufacturer or authorized distributors?
All STM6321MAWY6F 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 STM6321MAWY6F meets industry standards.
7.What is the process for return or replacement of STM6321MAWY6F?
All STM6321MAWY6F units undergo pre-shipment inspection (PSI). If there is an issue with STM6321MAWY6F, 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 STM6321MAWY6F part is unused and in its original packaging.
Return procedure for STM6321MAWY6F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
STM6321MAWY6F Tags
-
MIC826SYMT-TR
Microchip Technology
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APX803S-31SA-7
Diodes Incorporated
-
APX803L20-29SA-7
Diodes Incorporated
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TPS3828-33DBVR
Texas Instruments
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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
-
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
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