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STMicroelectronics TS420-700T
- Part No.:
- TS420-700T
- Manufacturer:
- STMicroelectronics
- Category:
- SCRs
- Package:
- TO-220-3
- Datasheet:
-
TS420-700T.pdf
- Description:
- SCR 700V 4A TO220AB
- Quantity:
- Payment:
- Shipping:
Inventory:8,375
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Product details
Overview
TS420-700T from STMicroelectronics is a sensitive-gate 4 A, 600 V RMS silicon-controlled rectifier (SCR) in TO-220AB package, with IGT ≤ 200 µA, VGT ≤ 0.8 V, and dV/dt immunity ≥ 5 V/µs at 125 °C. It serves as a low-power-triggered AC switch in crowbar protection circuits and universal motor controls where gate drive current is constrained.
For engineers reviewing the TS420-700T datasheet, TS420-700T pinout, TS420-700T application, or TS420-700T equivalent, key selection criteria include gate sensitivity (IGT), off-state voltage rating (VDRM/VRRM), thermal resistance (Rth(j-c) = 3.0 °C/W), turn-on timing (tGT = 0.5 µs typ.), and TO-220AB mechanical compatibility for heatsink mounting.
Technical Context
The TS420-700T operates as a unidirectional thyristor requiring gate-triggered latching conduction. Its ultra-low IGT (≤200 µA) enables direct drive from microcontroller GPIOs or low-current optocouplers without external amplification. The device sustains 600 V repetitive peak off-state voltage and exhibits robust dV/dt immunity (≥5 V/µs at Tj = 125 °C) due to optimized gate-cathode geometry.
Thermal performance is defined by Rth(j-c) = 3.0 °C/W (DC), supporting 4 A RMS on-state current at TC = 115 °C. Turn-off is circuit-controlled (not gate-controlled), relying on natural current zero-crossing or forced commutation, with tQ = 60 µs (typ.) under specified load and voltage conditions.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| IT(RMS) | 4 A - Sustains continuous AC load current up to 4 A RMS at TC = 115 °C |
| VDRM / VRRM | 600 V - Blocks up to 600 V peak reverse or forward voltage in off-state |
| IGT (max) | 200 µA - Triggers reliably with gate current ≤200 µA, enabling direct MCU/opto drive |
| dV/dt (min) | 5 V/µs - Immune to false triggering from rapid voltage transients at Tj = 125 °C |
| Rth(j-c) | 3.0 °C/W - Enables efficient heat transfer to heatsink; supports full 4 A rating with modest thermal design |
| tGT (typ) | 0.5 µs - Fast gate-controlled turn-on latency critical for precise phase-angle control |
| VTM (max) | 1.6 V - Low conduction loss at ITM = 8 A, reducing power dissipation during on-state |
Pinout & Package
TS420-700T uses the TO-220AB package: insulated tab, 3-pin through-hole, 2.3 g mass, with center pin (Pin 2) electrically connected to the tab (anode). Mounting torque: 0.4–0.6 N·m.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Tab & Pin 2) | Main current entry terminal | Electrically tied to metal tab; requires insulating washer if mounted to grounded heatsink |
| Cathode (Pin 1) | Main current exit terminal | Low-inductance path for load return; connects directly to load ground/reference |
| Gate (Pin 3) | Trigger control input | Sensitive input requiring ≤200 µA; must be decoupled with RC snubber in noisy environments |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low gate trigger current | IGT ≤ 200 µA enables direct drive from 3.3 V/5 V logic without buffer stages |
| High dV/dt immunity | ≥5 V/µs at 125 °C prevents spurious turn-on in high-noise AC line applications |
| Optimized thermal resistance | Rth(j-c) = 3.0 °C/W allows full 4 A RMS operation with standard TO-220 heatsinks |
| Robust surge capability | ITSM = 30 A (10 ms) supports brief overloads such as motor startup surges |
| Low on-state voltage | VTM ≤ 1.6 V at 8 A minimizes conduction losses and self-heating under load |
Applications
| Overvoltage Crowbar Protection | Universal Motor Speed Control |
|---|---|
Use Scenario: Protects low-power DC supplies (e.g., 12–24 V SMPS) against overvoltage faults by shorting output to ground when triggered by comparator. IC Role / Device Role / Timing Role: Latching crowbar switch activated once; remains on until power cycle or current interruption. Use Value: IGT ≤ 200 µA allows direct triggering from low-current comparators; 600 V VDRM ensures safe hold-off during transient spikes. | Use Scenario: Controls speed of brushed AC motors in hand tools (drills, sanders) via phase-angle firing. IC Role / Device Role / Timing Role: AC line switch synchronized to zero-crossing; conducts for adjustable conduction angle per half-cycle. Use Value: Fast tGT (0.5 µs) enables precise firing angle resolution; Rth(j-c) = 3.0 °C/W sustains 4 A RMS in compact tool housings. |
| Kitchen Appliance Power Control | AC Solid-State Relay Interface |
Use Scenario: Regulates heating element power in coffee makers or rice cookers using leading-edge phase control. IC Role / Device Role / Timing Role: Main power switching element driven by optocoupler-isolated gate signal. Use Value: VGD ≥ 0.1 V at 125 °C ensures reliable gate-cathode isolation under thermal stress; TO-220AB facilitates mechanical mounting near heater loads. | Use Scenario: Replaces electromechanical relays in industrial PLC output modules for silent, bounce-free switching. IC Role / Device Role / Timing Role: Output stage SCR switched by isolated gate driver; handles resistive/inductive loads up to 4 A RMS. Use Value: IH ≤ 5 mA and IL ≤ 6 mA ensure stable latching and clean turn-off at current zero; 30 A surge rating absorbs inductive kickback. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar SCR switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BT169G-TR | IGT = 50 µA (lower), VDRM = 400 V (lower), TO-92 package | Lower voltage rating limits use to ≤230 V AC systems; TO-92 unsuitable for >1 A RMS | Select only for space-constrained, low-voltage (<400 V) designs needing ultra-low IGT |
| TYN612 | IGT = 15 mA (higher), VDRM = 600 V, TO-220 package, Rth(j-c) = 2.5 °C/W | Requires gate buffer; better thermal performance but higher drive overhead | Prefer when gate drive strength is available and lower junction temperature is critical |
Compared with BT169G-TR and TYN612, TS420-700T uniquely balances ultra-low IGT (≤200 µA), 600 V blocking, and TO-220AB thermal capability-enabling direct MCU-driven crowbar and motor control without gate buffers or derating.
Availability
TS420-700T is available at Aetrix Electronics and suitable for overvoltage crowbar protection, universal motor control, kitchen appliance power regulation, and AC solid-state relay interfaces requiring stable component supply across production lifecycles.
Supply support for TS420-700T 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, microcontroller, and sensor solutions for industrial, automotive, and consumer markets.
The TS420 belongs to ST's high-sensitivity SCR product line, engineered specifically for applications where minimal gate drive capability exists-such as battery-powered tools, low-power SMPS protection, and cost-sensitive appliance controls.
FAQ
What is the maximum junction temperature for continuous operation?
The TS420-700T has a maximum operating junction temperature of +125 °C. Continuous operation at this temperature requires maintaining case temperature ≤115 °C per the IT(RMS) derating curve. Thermal design must ensure Rth(j-a) does not exceed limits when ambient exceeds 50 °C, especially in enclosed enclosures.
Can TS420-700T replace a TRIAC in AC phase-control circuits?
No-TS420-700T is a unidirectional SCR and conducts only during one half-cycle of AC. It cannot replace a bidirectional TRIAC unless used in a back-to-back configuration with a second SCR. For single-device phase control of full-wave AC, a TRIAC or dual-SCR module is required.
Is the TO-220AB tab electrically isolated from the leads?
No-the tab is internally connected to the anode (Pin 2). Electrical isolation requires a mica or polymer insulator plus shoulder washer during heatsink mounting. Failure to insulate may cause short circuits if the heatsink is grounded or at a different potential than the anode circuit.
What gate resistor value is recommended for reliable triggering?
A series gate resistor of 100 Ω to 470 Ω is recommended when driving from a 5 V logic source to limit IGM ≤1.2 A and damp ringing. Lower values improve noise immunity but increase gate power dissipation; values above 1 kΩ risk marginal triggering at elevated temperature due to IGT drift.
TS420-700T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- TO-220-3
- Packaging:
- Tube
- Product Status:
- Obsolete
- Voltage - Off State:
- 700 V
- Voltage - Gate Trigger (Vgt) (Max):
- 800 mV
- Current - Gate Trigger (Igt) (Max):
- 200 µA
- Voltage - On State (Vtm) (Max):
- 1.6 V
- Current - On State (It (AV)) (Max):
- 2.5 A
- Current - On State (It (RMS)) (Max):
- 4 A
- Current - Hold (Ih) (Max):
- 5 mA
- Current - Off State (Max):
- 5 µA
- Current - Non Rep. Surge 50, 60Hz (Itsm):
- 30A, 33A
- SCR Type:
- Sensitive Gate
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220
TS420-700T FAQ
1.How can I place an order for TS420-700T through Aetrix?
Please submit a Request for Quotation (RFQ) for TS420-700T 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 TS420-700T reliable?
The price and inventory of TS420-700T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TS420-700T is usually 5 days.
3.What payment methods are accepted for TS420-700T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TS420-700T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TS420-700T?
TS420-700T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TS420-700T 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 TS420-700T?
For technical support, including TS420-700T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TS420-700T requirements.
6.How does Aetrix verify that TS420-700T is sourced from the original manufacturer or authorized distributors?
All TS420-700T 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 TS420-700T meets industry standards.
7.What is the process for return or replacement of TS420-700T?
All TS420-700T units undergo pre-shipment inspection (PSI). If there is an issue with TS420-700T, 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 TS420-700T part is unused and in its original packaging.
Return procedure for TS420-700T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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