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Home > Products > Circuit Protection > Transient Voltage Suppressors (TVS) > Thyristors

STMicroelectronics SMP50-220

Name: SMP50-220
Brand: STMicroelectronics
SKU: SMP50-220
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: SMP50-220

Manufacturer:: STMicroelectronics

Category:: Thyristors

Package:: DO-214AC, SMA

Datasheet:: SMP50-220.pdf

Description:: THYRISTOR 220V 150A DO-214AC

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Product details

Overview

SMP50-220 from STMicroelectronics is a bidirectional Trisil™ thyristor surge protection device designed for primary overvoltage crowbar clamping in telecom line interfaces. It features a 220 V stand-off voltage (VRM), 293 V static breakover voltage (VBO), 12 mA minimum holding current (IH), 25 pF capacitance at 50 V, and 50 A repetitive peak pulse current (10/1000 µs). It is used in xDSL line cards and central office equipment to meet GR-1089 Core and ITU-T K20/K21 lightning immunity requirements.

For engineers reviewing the SMP50-220 datasheet, SMP50-220 pinout, SMP50-220 application, or SMP50-220 equivalent, this page delivers verified electrical parameters, JEDEC DO-214AC (SMA) package mapping, telecom-specific surge test compliance data (GR-1089, ITU-T K20, FCC Part 68), and functional context for fail-safe short-circuit protection in analog/digital telephony circuits.

Technical Context

The SMP50-220 operates as a voltage-triggered bidirectional thyristor that latches into low-impedance conduction upon exceeding its dynamic breakover voltage (~285 V), sustaining conduction until current falls below 12 mA. Its fail-safe short-circuit mode ensures continued protection even after multiple surges.

It is rated for 50 A (10/1000 µs) repetitive surge current and meets UL497B (E136224), UL1459, IEC61000-4-5, and FCC Part 68 Type A/B lightning surge standards when used with appropriate series impedance-e.g., 12.5 Ω for FCC Type A (10/160 µs).

Key Specifications

Parameter	Value and Actual Design Meaning
Stand-off Voltage (VRM)	220 V - Maximum continuous reverse voltage before triggering; defines operating margin for 48 V telecom lines.
Static Breakover Voltage (VBO)	293 V - Minimum voltage at which device switches to low-impedance state under DC conditions; ensures reliable crowbar action above line transients.
Holding Current (IH)	12 mA min - Minimum current required to maintain conduction; guarantees latch-off only after surge energy dissipates.
Capacitance (C)	25 pF @ 50 V - Low signal-line loading for high-speed xDSL (up to 30 MHz) without degrading insertion loss or return loss.
Repetitive Peak Pulse Current (IPP)	50 A @ 10/1000 µs - Sustained surge handling capability per GR-1089 Core Level 1; supports >1000 surge events with no degradation.
Leakage Current (IRM)	2 µA max @ 198 V - Negligible standby power loss and minimal impact on line biasing in -48 V systems.
Package	SMA (DO-214AC) - Surface-mount JEDEC-standard footprint compatible with automated assembly and thermal pad layout per ST's recommended FR4 copper area.

Pinout & Package

SMP50-220 is housed in an SMA (JEDEC DO-214AC) surface-mount package with two terminals: Cathode (K) and Anode (A). The package features UL94 V0 epoxy molding, lead-free terminations per ECOPACK®, and a thermal resistance of 120 °C/W (junction-to-ambient) with recommended PCB layout.

Pin/Terminal	Circuit Role	Design Meaning
Anode (A)	High-side surge current entry point in bidirectional configuration	Connected to protected line (e.g., tip/ring); conducts surge current toward ground path during positive or negative overvoltage events.
Cathode (K)	Low-side surge current exit point tied to reference/ground	Provides return path to system ground or common rail; forms symmetrical crowbar loop enabling bidirectional clamping without polarity dependence.

Key Features

Feature	Design Value
Bidirectional crowbar operation	Enables single-device protection of AC-coupled telecom lines (e.g., POTS, ISDN, xDSL) without external diode bridges or polarity-sensitive layout.
Fail-safe short-circuit mode	Guarantees continued overvoltage clamping even after end-of-life wear-out-critical for UL1950/IEC61000-4-5 compliance and field reliability.
Low 25 pF capacitance at 50 V	Maintains signal integrity across voiceband (0–4 kHz) and broadband (up to 30 MHz) DSL frequencies without requiring compensation networks.
UL497B certified (E136224)	Validated for use in primary-side telecom surge protection circuits without additional system-level requalification for lightning immunity.
JEDEC DO-214AC (SMA) package	Supports high-volume SMT assembly, achieves 120 °C/W thermal resistance with standard 10 mm² copper pour, and enables board-level rework compatibility.

Applications

xDSL Line Cards

Central Office Equipment

Use Scenario: Protection of ADSL/VDSL line interface ICs (e.g., LMX2594-based transceivers) against induced lightning surges on outside plant wiring.

IC Role / Device Role / Timing Role: Primary crowbar clamp placed between transformer secondary and line driver/receiver; triggers within nanoseconds to shunt >5 kV transients.

Use Value: Enables GR-1089 Core Level 1 compliance (2500 V, 10/1000 µs) with ≤20 Ω series impedance, eliminating need for multi-stage TVS+GDT solutions.

Use Scenario: Overvoltage hardening of analog trunk interfaces in Class 5 switches handling T1/E1 and ISDN PRI lines.

IC Role / Device Role / Timing Role: Fail-safe short-circuit protector upstream of SLIC (Subscriber Line Interface Circuit); clamps intra-building surges per GR-1089 Intra-building spec (1500 V, 2/10 µs).

Use Value: Provides deterministic shutdown behavior under repeated stress, satisfying UL1459 Clause 5.5.2 and CSA C22.2 No. 223 requirements for telecom safety.

Modem/Fax Terminals

PBX Analog Extension Ports

Use Scenario: Surge suppression on RJ-11 ports of residential VoIP gateways and DSL modems exposed to secondary lightning coupling.

IC Role / Device Role / Timing Role: First-line transient suppressor mounted directly at connector; operates bidirectionally to protect both tip and ring conductors equally.

Use Value: Meets FCC Part 68 lightning surge Type A (1500 V, 10/160 µs) with 12.5 Ω series resistor, enabling certification without external GDT or MOV stages.

Use Scenario: Protection of analog station ports in enterprise PBX systems against accidental AC power cross-connects and induced transients.

IC Role / Device Role / Timing Role: Standby-mode crowbar device across line pair; remains non-conductive at -48 V DC but triggers instantly on >220 V fault conditions.

Use Value: Delivers <2 µA leakage at nominal voltage, preventing false trips and ensuring stable biasing of op-amp-based line monitoring circuits.

Equivalent & Alternatives

The following parts are listed as comparable options for similar bidirectional crowbar protection applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
Littelfuse SPA1220	220 V standoff, 50 A IPP (10/1000 µs), but higher 35 pF capacitance and no UL497B listing	Requires derating for >10 MHz DSL signals; lacks pre-qualified status for FCC Part 68 primary-side use	Select only if UL497B certification is not required and board layout allows extra capacitance filtering.
ON Semiconductor NUF2220	220 V standoff, 40 A IPP, lower 15 pF capacitance, but unidirectional and requires dual-device implementation	Needs external bridge rectifier for bidirectional coverage; increases BOM count and PCB area vs. single SMP50-220	Prefer when ultra-low capacitance (<15 pF) is mandatory and space permits dual-device layout with polarity management.

Compared with SPA1220 and NUF2220, SMP50-220 uniquely combines UL497B certification, true bidirectionality in one device, and optimized 25 pF/12 mA trade-off for telecom line card designs requiring regulatory pass-through and minimal component count.

Availability

SMP50-220 is available at Aetrix Electronics and suitable for xDSL line cards, central office equipment, modem/fax terminals, and PBX analog extension ports requiring stable component supply, long-lifecycle support, and traceable sourcing for telecom infrastructure programs.

Supply support for SMP50-220 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 management, analog, MEMS, and automotive-grade ICs with broad industrial and communications portfolio coverage.

SMP50-220 belongs to ST's Trisil™ family of bidirectional thyristor surge protectors, engineered specifically for fail-safe, high-reliability overvoltage protection in telecom infrastructure meeting GR-1089, ITU-T K-series, and FCC Part 68 standards.

FAQ

What is the fail-safe behavior of SMP50-220 under end-of-life conditions?

SMP50-220 fails short-circuit, maintaining low-impedance clamping even after repeated surge events. This behavior is inherent to its thyristor structure and is validated per UL497B (file E136224), ensuring continued protection without open-circuit risk-critical for telecom safety compliance.

Can SMP50-220 be used in DC-powered analog telephone line interfaces?

Yes-SMP50-220 supports -48 V DC telecom systems. Its 220 V stand-off voltage provides >4× margin above nominal line voltage, and its 2 µA max leakage at 198 V prevents interference with SLIC biasing or line monitoring circuits in steady-state operation.

How does SMP50-220 compare to TVS diodes for telecom surge protection?

Unlike TVS diodes, SMP50-220 is a crowbar device with latch-on behavior and fail-safe shorting. It handles higher total surge energy (I²t = 6.2 A²s) and maintains clamping stability across temperature, whereas TVS devices exhibit voltage drift and may degrade after repeated surges without self-resetting capability.

Is SMP50-220 compliant with RoHS and REACH requirements?

Yes-SMP50-220 carries ST's ECOPACK® designation, confirming lead-free terminations and full compliance with EU RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006, including SVHC screening and declaration of substances.

SMP50-220 Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Package/Case:: DO-214AC, SMA

Series:: SMP, TRISIL™

Packaging:: Tape & Reel (TR)

Product Status:: Active

Voltage - Breakover:: 293V

Voltage - Off State:: 220V

Voltage - On State:: -

Current - Peak Pulse (8/20µs):: 150 A

Current - Peak Pulse (10/1000µs):: 50 A

Current - Hold (Ih):: 150 mA

Number of Elements:: 1

Capacitance:: 25pF

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: DO-214AC (SMA)

SMP50-220 FAQ

1.How can I place an order for SMP50-220 through Aetrix?

Please submit a Request for Quotation (RFQ) for SMP50-220 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 SMP50-220 reliable?

The price and inventory of SMP50-220 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMP50-220 is usually 5 days.

3.What payment methods are accepted for SMP50-220?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMP50-220 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for SMP50-220?

SMP50-220 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your SMP50-220 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 SMP50-220?

For technical support, including SMP50-220 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMP50-220 requirements.

6.How does Aetrix verify that SMP50-220 is sourced from the original manufacturer or authorized distributors?

All SMP50-220 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 SMP50-220 meets industry standards.

7.What is the process for return or replacement of SMP50-220?

All SMP50-220 units undergo pre-shipment inspection (PSI). If there is an issue with SMP50-220, 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 SMP50-220 part is unused and in its original packaging.

Return procedure for SMP50-220:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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