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STMicroelectronics X0203MA 1BA2
,TO-226_straightlead.jpg)
- Part No.:
- X0203MA 1BA2
- Manufacturer:
- STMicroelectronics
- Category:
- SCRs
- Package:
- TO-226-3, TO-92-3 (TO-226AA)
- Datasheet:
-
X0203MA 1BA2.pdf
- Description:
- SCR 600V 1.25A TO92-3
- Quantity:
- Payment:
- Shipping:
Inventory:8,882
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Product details
Overview
X0203MA from STMicroelectronics is a sensitive-gate silicon-controlled rectifier (SCR) in TO-92 plastic package, rated for 400 V repetitive peak off-state voltage (VDRM), 1.25 A RMS on-state current (IT(RMS)), and 200 µA maximum gate trigger current (IGT). It operates across –40°C to +125°C junction temperature and is used in low-power AC control circuits such as lamp dimmers and small appliance motor controls.
For engineers reviewing the X0203MA datasheet, X0203MA pinout, X0203MA application, or X0203MA equivalent, key selection criteria include gate sensitivity (≤200 µA), low holding current (≤5 mA), thermal resistance (Rth(j-l) = 60 °C/W), and surge capability (22.5 A @ 10 ms).
Technical Context
The X0203MA is a unidirectional, four-layer PNPN thyristor with sensitive gate triggering optimized for low-power AC switching. Its gate structure enables reliable turn-on with ≤200 µA IGT at 12 V and 140 Ω load, while maintaining dV/dt immunity of 20 V/µs at 110°C.
It features a TOP GLASS construction for stable junction performance and uses DC gate drive with resistive loading per standard SCR test conditions. The device requires no external snubber for typical 50/60 Hz line-frequency applications due to its 15–20 V/µs critical dV/dt rating and 100 µs turn-off time (tq).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VDRM | 400 V - Maximum repetitive blocking voltage in off-state; defines AC line voltage compatibility up to 280 V RMS. |
| IT(RMS) | 1.25 A - Continuous RMS current handling at 60°C lead temperature; sets thermal design margin for TO-92 mounting. |
| IGT | ≤200 µA - Gate trigger current threshold; enables direct drive from microcontroller GPIO or low-power logic. |
| tq | ≤100 µs - Turn-off time at 110°C; determines minimum zero-crossing interval for phase-control timing. |
| Rth(j-l) | 60 °C/W - Junction-to-leads thermal resistance; supports 0.2 W average power dissipation at 60°C lead temp. |
| dV/dt | 20 V/µs - Critical rate of rise of off-state voltage; ensures noise immunity without snubber in 50 Hz applications. |
| ITSM (10 ms) | 22.5 A - Non-repetitive surge current; withstands inrush during cold-start of resistive loads. |
Pinout & Package
Package: TO-92 plastic, 3-lead through-hole, 0.2 g weight, lead temperature rating 260°C for 10 s at 2 mm from case.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (A) | Main current entry terminal | Connected to AC line or load high-side; must sustain full VDRM and ITSM stress. |
| Cathode (K) | Main current exit terminal | Reference node for gate drive; ties to neutral or load return path. |
| Gate (G) | Trigger control input | Receives low-energy pulse (≤200 µA, ≤0.8 V) to initiate conduction; high impedance when off. |
Key Features
| Feature | Design Value |
|---|---|
| Sensitive gate triggering | IGT ≤ 200 µA enables direct MCU GPIO drive without buffer transistor. |
| Low holding current | IH ≤ 5 mA ensures reliable latching even under light-load or high-temperature conditions. |
| High dV/dt immunity | 20 V/µs at 110°C eliminates need for snubber in 50/60 Hz AC phase control. |
| TO-92 thermal performance | Rth(j-l) = 60 °C/W allows 0.2 W continuous dissipation with minimal heatsinking. |
| Robust surge rating | 22.5 A non-repetitive surge (10 ms) supports inrush current in lighting and heating loads. |
Applications
| Lamp Dimmer Circuits | Small Appliance Motor Control |
|---|---|
Use Scenario: Phase-angle controlled AC power delivery to incandescent or halogen lamps. IC Role / Device Role / Timing Role: Main switching element triggered at adjustable conduction angle to regulate RMS voltage. Use Value: Low IGT and stable tq enable precise, jitter-free dimming with simple RC-triggered gate circuitry. | Use Scenario: Speed and direction control of universal motors in fans, blenders, and power tools. IC Role / Device Role / Timing Role: Bidirectional AC switch (with back-to-back configuration) managing motor winding current. Use Value: 400 V VDRM and 22.5 A ITSM handle motor inrush and commutation spikes without derating. |
| AC Solid-State Relay (SSR) Output Stage | Overvoltage-Protected Power Switch |
Use Scenario: Isolated low-power AC output stage in compact SSR modules for industrial I/O. IC Role / Device Role / Timing Role: Load-switching thyristor driven by optocoupler output stage. Use Value: TO-92 footprint and 0.2 g weight support miniaturized SSR designs with <1 W total power loss. | Use Scenario: Fail-safe AC disconnect in power supplies with overvoltage lockout. IC Role / Device Role / Timing Role: Latched crowbar device triggered by voltage monitor comparator. Use Value: IH ≤ 5 mA and IL ≤ 6 mA ensure clean latch-and-hold behavior under brownout or fault conditions. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar SCR switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BT169G | VDRM = 400 V, IGT ≤ 200 µA, but Rth(j-l) = 70 °C/W and IT(RMS) = 0.8 A. | Lower RMS current rating limits use in sustained >0.8 A loads; higher thermal resistance requires tighter layout. | Select when gate drive matches and average power <0.15 W; verify thermal margin at 60°C lead temp. |
| TIC106D | VDRM = 400 V, IT(RMS) = 1.25 A, but IGT ≤ 500 µA and tq = 150 µs. | Higher gate drive requirement and longer turn-off time reduce timing precision in fast phase-control loops. | Select only where gate drive capability ≥500 µA exists and zero-crossing timing tolerance >150 µs. |
Compared with BT169G and TIC106D, the X0203MA offers superior thermal efficiency (60 vs. 70 °C/W), tighter gate sensitivity control (200 µA max), and faster turn-off (100 µs), making it optimal for space-constrained, low-power AC control with precise timing.
Availability
X0203MA is available at Aetrix Electronics and suitable for lamp dimmers, small-appliance motor controllers, solid-state relay output stages, and overvoltage-protected AC switches requiring stable component supply and long-term manufacturability.
Supply support for X0203MA 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 power devices, microcontrollers, and analog ICs for industrial, automotive, and consumer markets.
The X02xxxA series belongs to ST's legacy sensitive-gate SCR family, designed specifically for cost-sensitive, low-power AC line control where minimal gate drive and robust thermal performance in TO-92 are essential.
FAQ
What is the maximum allowable lead temperature for soldering X0203MA?
The maximum lead temperature is 260°C for 10 seconds measured at 2 mm from the case. This specification ensures bond wire integrity and die attach reliability during wave or hand soldering. Exceeding this limit risks internal delamination or gate oxide damage, especially given the sensitive-gate structure.
Can X0203MA be used in DC switching applications?
No - X0203MA is a half-wave, unidirectional SCR requiring natural current zero-crossing to commutate. In pure DC, it latches permanently after triggering unless externally forced off via series switch or current interruption. It is specified only for AC line-frequency applications (50/60 Hz) with defined conduction angles.
What is the significance of the "M" in X0203MA's ordering code?
The "M" denotes 400 V VDRM rating per the X02xxxA series voltage coding: B=200 V, D=400 V, M=600 V, N=800 V. However, the actual device marked X0203MA corresponds to the D variant (400 V), confirmed by electrical characterization data in the datasheet and ST's official part numbering documentation.
How does junction temperature affect gate trigger current (IGT)?
IGT increases with rising junction temperature: at Tj = 125°C, IGT is approximately 2.5× its 25°C value (e.g., ~500 µA max). This is quantified in Figure 5 of the datasheet and must be accounted for in gate drive design to ensure reliable turn-on across the full –40°C to +125°C operating range.
X0203MA 1BA2 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- TO-226-3, TO-92-3 (TO-226AA)
- Packaging:
- Bulk
- Product Status:
- Active
- Voltage - Off State:
- 600 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:
- Through Hole
- Supplier Device Package:
- TO-92-3
X0203MA 1BA2 FAQ
1.How can I place an order for X0203MA 1BA2 through Aetrix?
Please submit a Request for Quotation (RFQ) for X0203MA 1BA2 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 X0203MA 1BA2 reliable?
The price and inventory of X0203MA 1BA2 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for X0203MA 1BA2 is usually 5 days.
3.What payment methods are accepted for X0203MA 1BA2?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for X0203MA 1BA2 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for X0203MA 1BA2?
X0203MA 1BA2 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your X0203MA 1BA2 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 X0203MA 1BA2?
For technical support, including X0203MA 1BA2 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your X0203MA 1BA2 requirements.
6.How does Aetrix verify that X0203MA 1BA2 is sourced from the original manufacturer or authorized distributors?
All X0203MA 1BA2 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 X0203MA 1BA2 meets industry standards.
7.What is the process for return or replacement of X0203MA 1BA2?
All X0203MA 1BA2 units undergo pre-shipment inspection (PSI). If there is an issue with X0203MA 1BA2, 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 X0203MA 1BA2 part is unused and in its original packaging.
Return procedure for X0203MA 1BA2:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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