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STMicroelectronics X0205MA 2BL2
,TO-226_straightlead.jpg)
- Part No.:
- X0205MA 2BL2
- Manufacturer:
- STMicroelectronics
- Category:
- SCRs
- Package:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Datasheet:
-
X0205MA 2BL2.pdf
- Description:
- SCR 600V 1.25A TO92-3
- Quantity:
- Payment:
- Shipping:
Inventory:5,982
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Product details
Overview
X0205MA 2BL2 from STMicroelectronics is a sensitive-gate silicon-controlled rectifier (SCR) optimized for low-power triggering in crowbar protection, GFCI, and capacitive ignition circuits. It delivers 1.25 A RMS on-state current, 600 V repetitive peak off-state voltage (VDRM), and ultra-low gate trigger current of 50 µA (max), enabling reliable turn-on with minimal drive circuitry in space-constrained designs.
For engineers reviewing the X0205MA 2BL2 datasheet, X0205MA 2BL2 pinout, X0205MA 2BL2 application, or X0205MA 2BL2 equivalent, this device is selected where low IGT, robust dV/dt immunity (>15 V/µs), and TO-92 thermal performance (Rth(j-l) = 60 °C/W) are critical for fail-safe overvoltage shutdown and ignition timing control.
Technical Context
The X0205MA operates as a unidirectional thyristor with asymmetric gate triggering-designed to latch reliably at junction temperatures up to +125 °C and sustain 22.5 A non-repetitive surge current (tp = 10 ms, 60 Hz). Its 50 µA maximum IGT ensures compatibility with microcontroller GPIOs and low-power optocouplers without external amplification.
It features a dynamic on-state resistance (Rd) ≤200 mΩ at Tj = 125 °C and forward voltage drop (VT) ≤1.45 V at 2.5 A, minimizing conduction losses in pulsed-load applications. The device maintains ≥10 V/µs dV/dt immunity at 110 °C with 1 kΩ gate-cathode resistance, supporting stable operation in noisy power supply environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| IT(RMS) | 1.25 A - Sustains continuous load current in GFCI trip circuits and ignition coil drivers without heatsinking at TL ≤63 °C. |
| VDRM / VRRM | 600 V - Blocks line transients up to 600 V peak in 230 VAC mains-connected crowbar systems. |
| IGT (Q1) | 50 µA max - Enables direct drive from 3.3 V MCU pins or low-current optocouplers (e.g., PC817) without gate resistors. |
| dV/dt (min) | 15 V/µs - Resists false triggering from fast-rising noise in switching power supplies and motor drives. |
| VT (max) | 1.45 V @ 2.5 A - Limits conduction loss to <3.6 W at full RMS current, reducing thermal stress in TO-92 package. |
| IL / IH | Latching current ≤6 mA / Holding current ≤5 mA - Ensures clean turn-off during zero-crossing detection in AC phase-control schemes. |
| Rth(j-l) | 60 °C/W - Allows safe operation at 1.25 A RMS with lead temperature ≤63 °C, verified per Table 1 absolute ratings. |
Pinout & Package
Supplied in TO-92 package (3-lead, through-hole), with leads identified as Anode (A), Cathode (K), and Gate (G). Thermal design assumes lead temperature (TL) limited to 63 °C per absolute rating table.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A (Anode) | Main current entry terminal | Connected to high-side AC line or DC bus; must withstand full VDRM and IT(RMS) under conduction. |
| K (Cathode) | Main current exit terminal | Reference node for gate drive; ties to load return and defines common reference for triggering circuit. |
| G (Gate) | Control input for latching | Receives low-energy pulse (≥50 µA) to initiate conduction; requires no sustained drive after turn-on. |
Key Features
| Feature | Design Value |
|---|---|
| Sensitive gate trigger | 50 µA max IGT enables direct MCU/optocoupler interface without gate driver stages. |
| High dV/dt immunity | 15 V/µs minimum prevents spurious turn-on in EMI-rich power supply and motor control environments. |
| Low VT and Rd | 1.45 V VT and 200 mΩ Rd reduce power dissipation and thermal rise in TO-92 footprint. |
| Robust surge rating | 22.5 A non-repetitive surge (10 ms, 60 Hz) supports ignition coil energy discharge and transient crowbar events. |
Applications
| Ground Fault Circuit Interrupter (GFCI) | Overvoltage Crowbar Protection |
|---|---|
|
Use Scenario: Detects differential leakage current >5 mA and triggers immediate AC line disconnection via SCR latch. IC Role / Device Role / Timing Role: Latching switch that holds fault state until manual reset; triggered by comparator output pulse. Use Value: 50 µA IGT allows direct interface with low-power comparator outputs, eliminating gate buffer stages and saving board space. |
Use Scenario: Clamps regulated DC output (e.g., 12 V, 24 V) during overvoltage events by shorting to ground via series resistor. IC Role / Device Role / Timing Role: Fast-acting crowbar element activated by voltage monitor IC (e.g., TL431) when output exceeds threshold. Use Value: 15 V/µs dV/dt immunity prevents false triggering from regulator loop instability or load dump transients. |
| Capacitive Discharge Ignition (CDI) | AC Phase-Control Dimmer |
|
Use Scenario: Releases stored energy from HV capacitor into ignition coil primary winding at precise crank-angle timing. IC Role / Device Role / Timing Role: High-voltage, low-jitter switch triggered by microcontroller or Hall sensor signal. Use Value: 600 V VDRM safely isolates 400–500 V capacitor charge; 1.25 A IT(RMS) handles repetitive 10–20 A peak pulses. |
Use Scenario: Controls RMS power delivered to resistive loads (e.g., heaters, lamps) by adjusting conduction angle in each AC half-cycle. IC Role / Device Role / Timing Role: Bidirectional-triggered thyristor (used in back-to-back configuration) for leading-edge phase control. Use Value: 5 mA IH and 6 mA IL ensure stable hold-on during dimming at low conduction angles and prevent premature turn-off. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar sensitive-gate SCR applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ST X0205NA 2BL2 | 800 V VDRM/VRRM vs. 600 V; identical IGT (50 µA), IT(RMS) (1.25 A), and TO-92 package. | Used where higher line-voltage margin is required (e.g., 380 VAC industrial systems). | Select when system transient voltage exceeds 600 V peak; otherwise, X0205MA offers optimal cost/performance for 230 VAC designs. |
| Littelfuse S4006L | 600 V VDRM, 1.25 A IT(RMS), but IGT = 200 µA (max); TO-92 package; higher VT (1.7 V). | Requires stronger gate drive; less suitable for direct MCU interface in battery-powered GFCIs. | Choose only if gate drive capability exceeds 200 µA and thermal budget permits higher VT-related losses. |
Compared with X0205NA 2BL2, the X0205MA 2BL2 reduces gate drive burden and cost in 230 VAC applications; versus S4006L, it enables lower-power triggering and tighter thermal margins due to superior IGT and VT specs.
Availability
X0205MA 2BL2 is available at Aetrix Electronics and suitable for ground fault circuit interrupters, overvoltage crowbar protection in power supplies, and capacitive ignition circuits requiring stable component supply and long-term manufacturability.
Supply support for X0205MA 2BL2 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-energy triggering in safety-critical protection and timing circuits-prioritizing reliability, low IGT, and rugged surge performance in compact packages.
FAQ
What is the maximum junction temperature for continuous operation?
The X0205MA 2BL2 has an operating junction temperature range of –40 °C to +125 °C. Continuous operation at full 1.25 A RMS requires limiting lead temperature to 63 °C (per TO-92 absolute rating), which corresponds to ~125 °C junction under typical PCB copper layout conditions.
Can this SCR be triggered with a 3.3 V microcontroller GPIO?
Yes-its 50 µA maximum IGT and 0.8 V maximum VGT allow direct connection to a 3.3 V GPIO via a 33 kΩ series resistor (delivering ~100 µA), satisfying both voltage and current thresholds while providing noise margin and current limiting.
How does the X0205MA differ from the X0202MA variant?
The X0205MA specifies 50 µA maximum IGT and 600 V VDRM, whereas X0202MA specifies 200 µA maximum IGT and same 600 V rating. The "05" suffix denotes higher gate sensitivity, making X0205MA preferable for ultra-low-power trigger sources like CMOS logic or phototriac drivers.
Is the TO-92 package RoHS-compliant and halogen-free?
Yes-the TO-92 package uses lead-free plating and halogen-free molding resin, meeting STMicroelectronics' ECOPACK2 environmental standard. Full compliance documentation (including RoHS and REACH) is available in the DS2122 datasheet revision history and ST's product portal.
X0205MA 2BL2 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Packaging:
- Cut Tape (CT)
- Product Status:
- Active
- Voltage - Off State:
- 600 V
- Voltage - Gate Trigger (Vgt) (Max):
- 800 mV
- Current - Gate Trigger (Igt) (Max):
- 50 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:
- Through Hole
- Supplier Device Package:
- TO-92-3
X0205MA 2BL2 FAQ
1.How can I place an order for X0205MA 2BL2 through Aetrix?
Please submit a Request for Quotation (RFQ) for X0205MA 2BL2 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 X0205MA 2BL2 reliable?
The price and inventory of X0205MA 2BL2 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for X0205MA 2BL2 is usually 5 days.
3.What payment methods are accepted for X0205MA 2BL2?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for X0205MA 2BL2 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for X0205MA 2BL2?
X0205MA 2BL2 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your X0205MA 2BL2 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 X0205MA 2BL2?
For technical support, including X0205MA 2BL2 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your X0205MA 2BL2 requirements.
6.How does Aetrix verify that X0205MA 2BL2 is sourced from the original manufacturer or authorized distributors?
All X0205MA 2BL2 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 X0205MA 2BL2 meets industry standards.
7.What is the process for return or replacement of X0205MA 2BL2?
All X0205MA 2BL2 units undergo pre-shipment inspection (PSI). If there is an issue with X0205MA 2BL2, 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 X0205MA 2BL2 part is unused and in its original packaging.
Return procedure for X0205MA 2BL2:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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