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STMicroelectronics X0202NUF
- Part No.:
- X0202NUF
- Manufacturer:
- STMicroelectronics
- Category:
- SCRs
- Package:
- 3-SMB, Flat Leads
- Datasheet:
-
X0202NUF.pdf
- Description:
- SCR 800V 1.25A SMBFLAT-3L
- Quantity:
- Payment:
- Shipping:
Inventory:172
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Product details
Overview
X0202NUF from STMicroelectronics is a sensitive-gate silicon-controlled rectifier (SCR) rated for 1.25 A RMS on-state current and 800 V repetitive peak off-state voltage (VRRM), with gate trigger current of 200 µA max. It features low forward voltage drop (1.45 V max at 2.5 A), high dV/dt immunity (15 V/µs min), and is packaged in SMBflat-3L for surface-mount crowbar and GFCI applications requiring robust inrush handling and thermal stability.
For engineers reviewing the X0202NUF datasheet, X0202NUF pinout, X0202NUF application, or X0202NUF equivalent, this part supports precise low-current gate triggering in capacitive ignition, overvoltage protection, and ground fault interruption where high gate drive current is unavailable - critical for space-constrained industrial power supplies and safety-critical AC control circuits.
Technical Context
The X0202NUF operates as a unidirectional thyristor with asymmetric blocking capability (800 V reverse), optimized for phase-control and crowbar functions. Its 200 µA maximum IGT enables reliable turn-on from microcontroller GPIOs or low-power comparators without external amplification.
Thermal performance is defined by Rth(j-t) = 14 °C/W (junction-to-tab) and Rth(j-a) = 75 °C/W (junction-to-ambient, SOT-223/SMBflat-3L reference), supporting continuous operation up to Tj = +125 °C with appropriate PCB copper area. Holding current (IH ≤ 5 mA) and latching current (IL ≤ 6 mA) ensure stable conduction after triggering.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| IT(RMS) | 1.25 A - Supports sustained load current in compact AC switching applications without forced cooling |
| VRRM | 800 V - Blocks line transients in 230 VAC mains-connected protection circuits |
| IGT (max) | 200 µA - Enables direct drive from low-power logic or op-amp outputs |
| VT (max) | 1.45 V @ 2.5 A - Minimizes conduction loss and self-heating in crowbar paths |
| dV/dt (min) | 15 V/µs @ Tj = 110 °C - Resists false triggering from fast-rising noise in noisy power environments |
| IH (max) | 5 mA - Ensures reliable hold-on during low-current AC zero-crossing intervals |
| Rth(j-t) | 14 °C/W - Allows efficient heat transfer to PCB copper in SMBflat-3L footprint |
Pinout & Package
SMBflat-3L package: 3-terminal surface-mount plastic package with gull-wing leads, UL94 V0 epoxy, lead-free and halogen-free. Tab is electrically connected to cathode (K).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A (Anode) | Main current entry terminal | Carries full load current into device; must be routed with adequate trace width and clearance for 800 V isolation |
| K (Cathode) | Main current exit terminal & thermal tab connection | Connected to PCB thermal pad; serves as primary heat path and common reference for gate drive |
| G (Gate) | Trigger control input | Receives low-energy pulse to initiate conduction; requires <200 µA to guarantee turn-on at room temperature |
Key Features
| Feature | Design Value |
|---|---|
| Sensitive gate triggering | IGT ≤ 200 µA ensures compatibility with standard CMOS logic and low-power analog comparators |
| High dV/dt immunity | 15 V/µs minimum prevents spurious turn-on from EMI or switching noise in shared power rails |
| Low on-state voltage | VT ≤ 1.45 V reduces power dissipation and thermal stress in crowbar and ignition circuits |
| Robust surge rating | ITSM = 22.5 A (60 Hz, 10 ms) handles capacitor discharge surges without failure |
| Wide operating temperature | Tj = −40 to +125 °C supports deployment in automotive under-hood and industrial ambient conditions |
Applications
| Ground Fault Circuit Interrupter (GFCI) | Overvoltage Crowbar Protection |
|---|---|
Use Scenario: Detects leakage current imbalance (>5 mA) between line and neutral to disconnect AC mains within 25 ms. IC Role / Device Role / Timing Role: SCR acts as fast-acting latch and power switch triggered by comparator output. Use Value: Low IGT enables direct drive from low-power sensing circuitry; 800 V VRRM withstands transient overvoltages during fault clearing. |
Use Scenario: Clamps DC bus voltage during regulator failure or load dump in switched-mode power supplies. IC Role / Device Role / Timing Role: SCR shorts output to ground when Zener-triggered gate signal exceeds threshold. Use Value: 22.5 A non-repetitive surge rating absorbs energy from large bulk capacitors; low VT minimizes power loss during clamping. |
| Capacitive Ignition System | AC Motor Soft-Start Control |
Use Scenario: Discharges stored energy in ignition capacitor across primary winding to generate spark. IC Role / Device Role / Timing Role: SCR provides precise timing-controlled discharge path synchronized to engine position signal. Use Value: 15 V/µs dV/dt immunity prevents misfire from EMI in engine bays; SMBflat-3L package allows compact PCB layout near coil driver. |
Use Scenario: Gradually applies AC voltage to motor windings using phase-angle control to limit inrush current. IC Role / Device Role / Timing Role: SCR functions as half-wave or full-wave controlled rectifier in back-to-back configuration. Use Value: 1.25 A IT(RMS) supports small-induction-motor loads; IH ≤ 5 mA ensures stable conduction through low-current portions of AC cycle. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar SCR-based protection and switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STX0202NA | TO-92 package, Rth(j-l) = 60 °C/W, higher thermal resistance than SMBflat-3L | Better suited for through-hole prototyping or low-volume manual assembly | Select when board real estate permits larger footprint and thermal management relies on lead conduction rather than PCB copper |
| Littelfuse S4006L | 600 V VDRM, 6 A IT(RMS), IGT = 50 mA - significantly higher gate drive requirement | Requires dedicated gate driver; not suitable for direct MCU GPIO interface | Choose only when higher current rating and ruggedness outweigh need for sensitivity and compact packaging |
Compared with STX0202NA and S4006L, X0202NUF uniquely balances ultra-low gate sensitivity (200 µA), 800 V blocking, and SMBflat-3L thermal efficiency - making it optimal for automated SMT production of space-constrained, low-power-triggered protection circuits.
Availability
X0202NUF is available at Aetrix Electronics and suitable for ground fault interruption, overvoltage crowbar protection, and capacitive ignition systems requiring stable component supply, RoHS-compliant packaging, and consistent parametric performance across manufacturing lots.
Supply support for X0202NUF 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, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.
The X02 series is ST's dedicated family of sensitive-gate SCRs engineered for low-power-triggered AC control and fail-safe protection - emphasizing reliability, thermal resilience, and ease of integration in safety-critical power interfaces.
FAQ
What is the maximum gate-cathode resistance allowed for reliable triggering of X0202NUF?
The datasheet specifies that dV/dt immunity degrades with increasing RGK; Figure 7 shows ≥10 kΩ reduces immunity below 15 V/µs. For guaranteed turn-on at all temperatures and voltages, RGK should not exceed 1 kΩ - matching the test condition used for IGT and dV/dt characterization in Table 2.
Can X0202NUF be used in bidirectional AC switching applications?
No - X0202NUF is a unidirectional SCR with 800 V forward blocking (VRRM) but only 5 V reverse gate-cathode breakdown (VRG). It cannot block reverse voltage across anode-cathode and must be used with external diodes or in back-to-back configuration with a second SCR for full-wave AC control.
What PCB copper area is recommended beneath the SMBflat-3L tab for thermal performance?
Per Figure 12 and Table 4, Rth(j-a) drops from 75 °C/W to ~40 °C/W with 5 cm² of 2-oz copper under the tab. A minimum of 2 cm² is recommended for continuous 1.25 A operation at Tj ≤ 125 °C in still air; thermal vias to inner layers further improve dissipation.
Does X0202NUF meet automotive AEC-Q101 requirements?
No - X0202NUF is qualified per industrial standards (−40 to +125 °C operation, ECOPACK2 compliance), but ST does not list it in its AEC-Q101 qualified portfolio. For automotive applications, ST recommends the AEC-Q101-certified TN1215 series SCRs with comparable sensitivity and ratings.
X0202NUF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- 3-SMB, Flat Leads
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Off State:
- 800 V
- Voltage - Gate Trigger (Vgt) (Max):
- 800 mV
- Current - Gate Trigger (Igt) (Max):
- 200 µA
- Voltage - On State (Vtm) (Max):
- 1.45 V
- Current - On State (It (AV)) (Max):
- 800 mA
- Current - On State (It (RMS)) (Max):
- 1.25 A
- Current - Hold (Ih) (Max):
- 5 mA
- Current - Off State (Max):
- 5 µA
- Current - Non Rep. Surge 50, 60Hz (Itsm):
- 22.5A, 25A
- SCR Type:
- Sensitive Gate
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMBflat-3L
X0202NUF FAQ
1.How can I place an order for X0202NUF through Aetrix?
Please submit a Request for Quotation (RFQ) for X0202NUF 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 X0202NUF reliable?
The price and inventory of X0202NUF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for X0202NUF is usually 5 days.
3.What payment methods are accepted for X0202NUF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for X0202NUF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for X0202NUF?
X0202NUF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your X0202NUF 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 X0202NUF?
For technical support, including X0202NUF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your X0202NUF requirements.
6.How does Aetrix verify that X0202NUF is sourced from the original manufacturer or authorized distributors?
All X0202NUF 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 X0202NUF meets industry standards.
7.What is the process for return or replacement of X0202NUF?
All X0202NUF units undergo pre-shipment inspection (PSI). If there is an issue with X0202NUF, 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 X0202NUF part is unused and in its original packaging.
Return procedure for X0202NUF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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