My Inquiry
My Account
STMicroelectronics STM6322LWY6F
- Part No.:
- STM6322LWY6F
- Manufacturer:
- STMicroelectronics
- Category:
- Supervisors
- Package:
- SC-74A, SOT-753
- Datasheet:
-
STM6322LWY6F.pdf
- Description:
- IC SUPERVISOR 1 CHANNEL SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,012
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
STM6322LWY6F from STMicroelectronics is a 5-pin precision voltage supervisor IC with integrated watchdog timer and manual reset input, designed for microprocessor reset management in industrial embedded systems. It monitors 3.3 V power supplies, asserts active-low open-drain RST output, provides 1.4 ms reset pulse width (typ.), 1.6 s watchdog timeout (typ.), and guarantees reset assertion down to VCC = 1.0 V - used in programmable logic controllers and motor control modules requiring reliable power-on and fault recovery.
For engineers reviewing the STM6322LWY6F datasheet, STM6322LWY6F pinout, STM6322LWY6F application, or STM6322LWY6F equivalent, key selection criteria include reset threshold accuracy (±1.5% at 3.3 V), low 3 µA supply current (typ.), SOT23-5 package compatibility, MR input with internal 52 kΩ pull-up, and open-drain RST output requiring external pull-up for multi-rail interfacing.
Technical Context
The STM6322LWY6F implements a precision bandgap reference and comparator to monitor VCC against a fixed 3.3 V reset threshold (VRST = 3.3 V ±1.5%). Its watchdog circuit triggers reset if WDI remains static for ≥1.6 s (typ.), and clears on any WDI edge (≥50 ns pulse width supported).
Reset assertion is guaranteed valid down to VCC = 1.0 V over –40 to +85 °C, with trec = 1.4 ms (typ.) after power-up or MR release. The open-drain RST output requires an external pull-up resistor (e.g., 10 kΩ) and supports interfacing across voltage domains up to 6 V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reset Threshold | 3.3 V ±1.5% - ensures accurate brown-out detection for 3.3 V systems without external calibration |
| Reset Pulse Width | 1.4 ms (typ.) - meets minimum reset hold time requirements of ARM Cortex-M and PIC microcontrollers |
| Watchdog Timeout | 1.6 s (typ.) - provides sufficient margin to detect firmware lockup while avoiding false triggers during long ISR execution |
| Supply Current | 3 µA (typ.) at VCC < 3.6 V - enables use in battery-backed or ultra-low-power monitoring circuits |
| Operating Temp | –40 to +85 °C - qualified for industrial-grade operation in factory automation and outdoor equipment |
| VCC Range | 1.0 to 5.5 V - allows supervision of 3.3 V rails while remaining functional during deep brown-out conditions |
| MR Input Pull-up | 52 kΩ internal - eliminates need for external pull-up; supports direct switch-to-ground connection without debounce circuitry |
Pinout & Package
The STM6322LWY6F 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 PCB 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 function |
| 2 - VCC | Supply voltage | Primary power input; monitored for out-of-tolerance condition; operates from 1.0 V to 5.5 V |
| 3 - RST | Active-low open-drain reset output | Sinks current when asserted; requires external pull-up to system rail (≤6 V); supports level-shifting |
| 4 - MR | Manual reset input | Active-low; internally pulled up to VCC via 52 kΩ; asserts reset while low and for 1.4 ms after release |
| 5 - VSS | Ground | Reference return path for all internal comparators and outputs; must be low-impedance connection |
Key Features
| Feature | Design Value |
|---|---|
| Precision 3.3 V monitoring | ±1.5% threshold tolerance over temperature ensures consistent reset behavior without trimming components |
| Open-drain RST output | Enables wired-OR reset bus configuration and safe interfacing with mixed-voltage microcontrollers (e.g., 1.8 V I/O with 3.3 V VCC) |
| Guaranteed reset to 1.0 V | Ensures valid reset signal even during severe brown-out, preventing MCU runaway before full power collapse |
| Low 3 µA quiescent current | Reduces standby power in always-on monitoring applications such as smart sensors and remote I/O modules |
| Integrated MR pull-up | Eliminates external resistor; simplifies BOM and layout for push-button reset implementation with no additional components |
Applications
| Industrial PLC I/O Module | Motor Drive Control Board |
|---|---|
|
Use Scenario: Monitors 3.3 V logic rail powering FPGA configuration memory and gate driver interface logic. IC Role / Device Role / Timing Role: Supervisor IC asserting open-drain RST to hold FPGA in reset until stable 3.3 V is confirmed; MR input tied to front-panel emergency stop button. Use Value: Prevents partial FPGA configuration and invalid gate drive signals during power ramp; 1.4 ms reset pulse exceeds Xilinx Spartan-7 minimum requirement. |
Use Scenario: Supervises 3.3 V supply feeding MCU and isolated gate driver bias rails in a 3-phase inverter. IC Role / Device Role / Timing Role: Resets MCU and forces gate drivers into safe-off state via shared RST line; watchdog monitors firmware health during PWM generation. Use Value: Open-drain RST allows co-location with optocoupler-isolated reset paths; 1.6 s watchdog timeout accommodates worst-case ADC sampling + PID loop cycles. |
| Smart Energy Meter | Factory Automation Sensor Node |
|
Use Scenario: Ensures clean startup of metrology SoC and secure element after battery backup switchover. IC Role / Device Role / Timing Role: Provides power-on reset and brown-out protection; MR input connected to tamper-detection switch. Use Value: Guaranteed reset assertion down to VCC = 1.0 V prevents cryptographic key corruption during battery depletion events. |
Use Scenario: Manages reset sequencing for ultra-low-power MCU and wireless transceiver in battery-powered predictive maintenance sensor. IC Role / Device Role / Timing Role: Generates reset pulse on power-up and responds to watchdog timeout if BLE stack hangs; MR used for field firmware recovery. Use Value: 3 µA supply current extends 10-year battery life; internal MR pull-up reduces component count in space-constrained enclosure. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar voltage supervisor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX6322US33D3+ | 3.3 V ±2.5% threshold; 1.5 ms reset pulse; 2.5 µA ICC; same SOT23-5 package | No watchdog timer; MR input lacks internal pull-up (requires external 100 kΩ) | Select when watchdog functionality is unnecessary and lowest possible quiescent current is critical |
| TPS3808G33DBVR | 3.3 V ±0.5% threshold; 200 ms reset pulse; 1.1 µA ICC; 6-pin SOT23 package | Push-pull RST output only; no open-drain option; requires separate MR pull-up | Select when higher threshold accuracy and longer reset hold time are required, and board space permits 6-pin layout |
Compared with MAX6322US33D3+ and TPS3808G33DBVR, the STM6322LWY6F uniquely combines open-drain RST, integrated MR pull-up, and watchdog timer in a 5-pin SOT23-5 footprint - enabling compact, self-contained reset supervision for cost-sensitive industrial designs where multi-rail compatibility and field serviceability matter.
Availability
STM6322LWY6F is available at Aetrix Electronics and suitable for industrial PLCs, motor control drives, smart energy meters, and factory automation sensor nodes requiring stable component supply across extended product lifecycles.
Supply support for STM6322LWY6F 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, specializing in microcontrollers, power management, and analog/mixed-signal ICs for industrial, automotive, and consumer markets.
The STM6xxx series was developed specifically for robust, low-power microprocessor supervision in harsh industrial environments - emphasizing precision threshold stability, wide operating voltage range, and simplified manual reset integration.
FAQ
What is the reset threshold voltage for STM6322LWY6F?
The STM6322LWY6F has a fixed reset threshold of 3.3 V with ±1.5% tolerance over temperature (–40 to +85 °C). This value is factory-trimmed and does not require external resistors or calibration. It is specified in Table 6 of the datasheet (DocID11110 Rev 14) under VRST, with typical values measured at 3.3 V and min/max bounds of 3.25 V and 3.35 V respectively.
Can the watchdog function be disabled?
Yes - the watchdog function is automatically disabled when the WDI pin is left unconnected or driven by a tristate buffer. In this state, the internal watchdog counter stops counting, and no reset is generated due to watchdog timeout. The datasheet confirms this behavior in Section 2.4 and Figure 26, noting that leakage current must remain below 10 µA and load capacitance under 200 pF for reliable disable operation.
What pull-up resistor value is recommended for the RST output?
A 10 kΩ pull-up resistor to the target system rail (≤6 V) is recommended for the open-drain RST output. This value ensures logic-high recognition across common I/O thresholds (e.g., 70% of 3.3 V = 2.31 V) while limiting sink current to ≤330 µA when asserted - well within the 20 mA absolute maximum rating. The datasheet validates this in Figure 11 and Section 2.2.
Does STM6322LWY6F support interfacing with bidirectional MCU reset pins?
Yes - the STM6322LWY6F can safely interface with bidirectional reset I/O using a 4.7 kΩ series resistor between RST and the MCU pin, as shown in Figure 14 of the datasheet. This resistor prevents contention when both devices attempt to drive the line simultaneously, ensuring reliable reset assertion without damaging either device's output stage.
STM6322LWY6F 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:
- 4.63V
- Output:
- Open Drain, Push-Pull
- Reset:
- Active High/Active Low
- Reset Timeout:
- 140ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
STM6322LWY6F FAQ
1.How can I place an order for STM6322LWY6F through Aetrix?
Please submit a Request for Quotation (RFQ) for STM6322LWY6F 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 STM6322LWY6F reliable?
The price and inventory of STM6322LWY6F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STM6322LWY6F is usually 5 days.
3.What payment methods are accepted for STM6322LWY6F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STM6322LWY6F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for STM6322LWY6F?
STM6322LWY6F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your STM6322LWY6F 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 STM6322LWY6F?
For technical support, including STM6322LWY6F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STM6322LWY6F requirements.
6.How does Aetrix verify that STM6322LWY6F is sourced from the original manufacturer or authorized distributors?
All STM6322LWY6F 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 STM6322LWY6F meets industry standards.
7.What is the process for return or replacement of STM6322LWY6F?
All STM6322LWY6F units undergo pre-shipment inspection (PSI). If there is an issue with STM6322LWY6F, 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 STM6322LWY6F part is unused and in its original packaging.
Return procedure for STM6322LWY6F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
STM6322LWY6F 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 and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
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…
