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STMicroelectronics TN4050-12PI
- Part No.:
- TN4050-12PI
- Manufacturer:
- STMicroelectronics
- Category:
- SCRs
- Package:
- TOP-3
- Datasheet:
-
TN4050-12PI.pdf
- Description:
- SCR 1.2KV 40A TOP3
- Quantity:
- Payment:
- Shipping:
Inventory:74
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Product details
Overview
TN4050-12PI from STMicroelectronics is a 40 A, 1200 V standard silicon-controlled rectifier (SCR) in a TOP3 isolated-tab through-hole package, featuring 50 mA maximum gate trigger current, 100 A/µs critical dI/dt, and 2000 V/µs dV/dt immunity. It is UL1557 certified (2.5 kV RMS isolation), RoHS- and HF-compliant (ECOPACK2), and designed for high-immunity industrial AC power control including solar inverters, UPS systems, and soft starters.
For engineers reviewing the TN4050-12PI datasheet, TN4050-12PI pinout, TN4050-12PI application, or TN4050-12PI equivalent, key selection criteria include RMS current rating (40 A), blocking voltage (1200 V), gate sensitivity (≤50 mA), thermal resistance (1.1 °C/W j-c), and UL-certified isolation integrity for safety-critical AC line switching.
Technical Context
This SCR operates as a unidirectional, gate-triggered power switch for phase-controlled rectification and AC line commutation. Its high dV/dt (2000 V/µs) and dI/dt (100 A/µs) ratings enable reliable turn-on under fast-rising transients and noisy industrial bus conditions without false triggering or commutation failure.
The device uses a ceramic-isolated tab for reinforced insulation (UL1557, 2.5 kV RMS), with junction-to-case thermal resistance of 1.1 °C/W enabling direct heatsink mounting. Gate threshold voltage is ≤1.5 V at 25 °C, and holding current remains ≤100 mA up to 125 °C junction temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VDRM/VRRM | 1200 V - Maximum repetitive blocking voltage across anode-cathode, defining safe AC line voltage operation up to 850 V RMS. |
| IT(RMS) | 40 A - Continuous RMS on-state current at Tc = 82.5 °C, supporting 5.3 kW resistive load at 132 V RMS. |
| IGT max | 50 mA - Maximum gate trigger current required for reliable turn-on, enabling low-power driver IC compatibility. |
| dV/dt min | 2000 V/µs - Minimum rate-of-rise of off-state voltage before spurious turn-on, ensuring noise immunity in SMPS and welding systems. |
| Rth(j-c) | 1.1 °C/W - Junction-to-case thermal resistance, allowing direct heatsink mounting with predictable temperature rise under full load. |
| VTM max | 1.75 V - Maximum on-state voltage drop at 80 A pulse, limiting conduction loss to ≤140 W peak and enabling efficient thermal design. |
| UL1557 Rating | 2.5 kV RMS - Reinforced isolation voltage between case and terminals, satisfying safety requirements for mains-connected equipment. |
Pinout & Package
Package: TOP3 isolated-tab through-hole package with ceramic-insulated metal tab (A-K-G pin configuration), UL94-V0 resin housing, and 1.05 N·m recommended mounting torque.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (A) | Main current entry terminal | Carries full load current into device; electrically isolated from tab by ceramic layer per UL1557. |
| Cathode (K) | Main current exit terminal | Connected to load return path; referenced to gate drive ground in most phase-control circuits. |
| Gate (G) | Trigger control input | Receives low-energy pulse (≤50 mA, ≤1.5 V) to initiate conduction; requires no continuous bias. |
| Tab (Isolated) | Thermal interface / mechanical mount | Electrically isolated metal surface for heatsink attachment; rated 2.5 kV RMS isolation from all pins. |
Key Features
| Feature | Design Value |
|---|---|
| UL1557-certified isolation | 2.5 kV RMS reinforced insulation enables direct mains connection without additional barrier components. |
| High dV/dt immunity | 2000 V/µs minimum prevents false triggering in EMI-heavy environments like welding or motor drives. |
| Ceramic-isolated tab | Enables direct heatsink mounting while maintaining safety isolation-no insulating washer required. |
| ECOPACK2 compliance | Lead-free plating and halogen-free UL94-V0 resin meet global environmental and flammability standards. |
| Low IGT sensitivity | Guaranteed turn-on with ≤50 mA gate current simplifies driver design and reduces gate drive power loss. |
Applications
| Solar Inverter DC Link Switching | Uninterruptible Power Supply (UPS) Bypass |
|---|---|
Use Scenario: Controlling bidirectional energy flow between PV array and grid-tied inverter DC link during anti-islanding protection or fault isolation. IC Role / Device Role / Timing Role: SCR acts as a high-voltage, high-current latching switch triggered at zero-crossing to isolate DC bus segments. Use Value: 1200 V blocking and 40 A RMS rating support 1000 V DC systems; ceramic isolation eliminates need for opto-isolated gate drivers in safety-critical disconnect paths. | Use Scenario: Providing seamless transfer from inverter output to utility bypass during overload or inverter failure in double-conversion UPS. IC Role / Device Role / Timing Role: SCR serves as a fast-acting, low-loss AC transfer switch synchronized to line zero-crossing for glitch-free switchover. Use Value: 100 A/µs dI/dt and 2000 V/µs dV/dt ensure reliable commutation under transient overloads; UL1557 certification satisfies safety agency requirements for redundant AC paths. |
| Industrial Soft Starter | AC/DC Inrush Current Limiter (ICL) |
Use Scenario: Gradually ramping motor voltage during startup using phase-angle control to limit mechanical stress and peak current draw. IC Role / Device Role / Timing Role: SCR functions as a controllable AC voltage regulator via gate timing relative to AC zero-crossing. Use Value: Low 50 mA IGT allows direct microcontroller GPIO driving with minimal external circuitry; 40 A RMS rating supports motors up to 15 kW at 400 V. | Use Scenario: Limiting surge current into large capacitor banks during AC/DC converter power-up to prevent fuse blowing and contact welding. IC Role / Device Role / Timing Role: SCR placed in series with primary winding, triggered after initial NTC cooldown to short out limiting resistor. Use Value: 420 A non-repetitive surge rating handles 10 ms inrush peaks; isolated tab enables safe integration into transformer-primary-side high-voltage circuits. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar SCR-based AC power control applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| IXYS MCR40-12IO1 | Same 40 A/1200 V rating; higher IGT (100 mA); TO-247 package with non-isolated tab. | Requires insulating hardware for heatsink mounting; lacks UL1557 certification. | Select when cost is prioritized over safety certification and isolation simplicity. |
| Littelfuse S4012L | 40 A/1200 V; lower dV/dt (1000 V/µs); same TOP3 isolated package; RoHS only (no HF or ECOPACK2). | Not UL1557 certified; reduced noise immunity limits use in high-EMI welding or SMPS. | Select when ECOPACK2 and UL1557 are not required, and legacy Littelfuse supply chain is preferred. |
Compared with MCR40-12IO1 and S4012L, the TN4050-12PI uniquely combines UL1557 isolation, ECOPACK2 compliance, and 2000 V/µs dV/dt-enabling simplified, safety-certifiable designs in solar inverters and UPS bypass where regulatory approval and noise resilience are mandatory.
Availability
TN4050-12PI is available at Aetrix Electronics and suitable for solar inverters, uninterruptible power supplies (UPS), and industrial soft starters requiring stable component supply, long-term lifecycle support, and certified isolation performance.
Supply support for TN4050-12PI 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, power, MCU, and sensor solutions for industrial, automotive, and consumer markets.
The TN4050-12PI belongs to ST's high-power SCR product line, engineered specifically for robust, safety-certified AC power switching in renewable energy, UPS, and industrial motor control applications.
FAQ
What is the maximum allowable gate trigger voltage for TN4050-12PI?
The maximum peak positive gate voltage (VGM) is 5 V, tested with 20 µs pulse width at Tj = 125 °C. Exceeding this may damage the gate junction. Typical VGT is ≤1.5 V at 25 °C, and gate drive circuits must limit both voltage and current (IGM ≤ 8 A peak) to ensure reliability across temperature.
Can TN4050-12PI be used in DC applications?
No-it is a standard SCR optimized for AC line-commutated operation. It lacks forced commutation capability and cannot self-turn-off in DC circuits. For DC switching, a GTO, IGBT, or MOSFET with active gate control is required. Its holding current (IH ≤ 100 mA) and latching current (IL ≤ 130 mA) assume AC zero-crossing for natural commutation.
What is the thermal derating behavior above 82.5 °C case temperature?
Average on-state current (IT(AV)) decreases linearly above 82.5 °C case temperature, reaching zero at ~125 °C. Figure 2 in DS12925 shows IT(AV) = 40 A at 82.5 °C, dropping to ~25 A at 100 °C and ~12 A at 115 °C for 180° conduction angle-requiring heatsink oversizing or forced cooling for sustained high-temp operation.
Does TN4050-12PI require a snubber circuit in typical applications?
A snubber is recommended when switching inductive loads or operating near dV/dt limits. With 2000 V/µs immunity, it withstands typical 50/60 Hz line transients without snubbing-but for high-dI/dt loads (e.g., welding transformers), an RC snubber across A–K improves reliability by limiting dv/dt during turn-off and suppressing voltage spikes from leakage inductance.
TN4050-12PI Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- ECOPACK®2
- Package/Case:
- TOP-3
- Packaging:
- Tube
- Product Status:
- Active
- Voltage - Off State:
- 1.2 kV
- Voltage - Gate Trigger (Vgt) (Max):
- 1.5 V
- Current - Gate Trigger (Igt) (Max):
- 50 mA
- Voltage - On State (Vtm) (Max):
- 1.75 V
- Current - On State (It (AV)) (Max):
- 25 A
- Current - On State (It (RMS)) (Max):
- 40 A
- Current - Hold (Ih) (Max):
- 100 mA
- Current - Off State (Max):
- 10 µA
- Current - Non Rep. Surge 50, 60Hz (Itsm):
- 400A, 420A
- SCR Type:
- Standard Recovery
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TOP3
TN4050-12PI FAQ
1.How can I place an order for TN4050-12PI through Aetrix?
Please submit a Request for Quotation (RFQ) for TN4050-12PI 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 TN4050-12PI reliable?
The price and inventory of TN4050-12PI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TN4050-12PI is usually 5 days.
3.What payment methods are accepted for TN4050-12PI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TN4050-12PI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TN4050-12PI?
TN4050-12PI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TN4050-12PI 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 TN4050-12PI?
For technical support, including TN4050-12PI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TN4050-12PI requirements.
6.How does Aetrix verify that TN4050-12PI is sourced from the original manufacturer or authorized distributors?
All TN4050-12PI 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 TN4050-12PI meets industry standards.
7.What is the process for return or replacement of TN4050-12PI?
All TN4050-12PI units undergo pre-shipment inspection (PSI). If there is an issue with TN4050-12PI, 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 TN4050-12PI part is unused and in its original packaging.
Return procedure for TN4050-12PI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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