STMicroelectronics SMP50-200

Overview

SMP50-200 from STMicroelectronics is a bidirectional Trisil™ thyristor surge protector designed for primary overvoltage clamping in telecom line interfaces. It features 200 V stand-off voltage (VRM), 262 V dynamic breakover voltage (VBO), 12 mA minimum holding current (IH), 50 A repetitive peak pulse current (10/1000 µs), and 25 pF capacitance at 50 V - enabling robust lightning protection in xDSL and T1/E1 line cards without signal integrity degradation.

For engineers reviewing the SMP50-200 datasheet, SMP50-200 pinout, SMP50-200 application, or SMP50-200 equivalent, this device is selected for fail-safe short-circuit behavior under surge, UL497B and GR-1089 compliance, low-leakage operation (<2 µA), and SMA package compatibility with high-density PCB layouts in telecom infrastructure.

Technical Context

The SMP50-200 operates as a crowbar-type transient voltage suppressor: it remains high-impedance below VRM (200 V), triggers into low-impedance conduction at VBO (262 V typ.), and latches on until current falls below IH (12 mA min). Its bidirectional symmetry enables AC line protection without polarity constraints.

Thermal design relies on Rth(j-a) = 120 °C/W (SMA package) and IFS = 2.5 kA (8/20 µs fail-safe short-circuit rating), ensuring survivability during multi-kA surges while maintaining UL94 V0 flammability compliance and JEDEC DO-214AC footprint registration.

Key Specifications

Pinout & Package

SMP50-200 is housed in an SMA package (JEDEC DO-214AC), surface-mountable with gull-wing leads. The device is bidirectional and symmetrical: both terminals serve identical roles in AC line protection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMP50-180 and SMP50-220, the SMP50-200 offers optimal balance between 48 V system compatibility and margin against 2500 V GR-1089 surges - making it the default selection for standard xDSL and T1/E1 line card designs requiring validated UL497B performance at 200 V nominal.

Availability

SMP50-200 is available at Aetrix Electronics and suitable for xDSL line cards, T1/E1 digital trunk interfaces, ISDN terminal equipment, and central office line cards requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for SMP50-200 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, microcontroller, power, and protection devices for industrial, automotive, and communications markets.

The Trisil™ product line was developed specifically for fail-safe, high-energy surge protection in telecom infrastructure - emphasizing crowbar reliability, regulatory compliance (UL497B, GR-1089), and long-term stability in harsh electrical environments.

FAQ

What is the fail-safe behavior of SMP50-200 during surge events?

The SMP50-200 enters a permanent short-circuit state when subjected to surges exceeding its IFS rating (2.5 kA, 8/20 µs), providing deterministic fault indication and preventing latent degradation. This behavior is intrinsic to its thyristor structure and is validated per UL497B file E136224 - unlike MOVs or TVS diodes that may degrade silently.

Can SMP50-200 be used in AC line applications without polarity concerns?

Yes - SMP50-200 is a fully bidirectional device with symmetrical Anode/Cathode terminals. Its identical forward and reverse characteristics eliminate polarity marking requirements and simplify layout in AC-coupled telecom interfaces such as xDSL and ISDN, where line transformers deliver floating differential signals.

How does SMP50-200 compare to standard TVS diodes in telecom surge protection?

Unlike unidirectional TVS diodes, SMP50-200 provides crowbar action with latch-on behavior and fail-safe shorting, offering superior energy handling (50 A, 10/1000 µs) and immunity to aging. Its 25 pF capacitance is comparable to low-capacitance TVS devices but with higher surge endurance and regulatory validation for primary-side telecom use.

Is SMP50-200 compliant with modern telecom standards like GR-1089 and ITU-T K20?

Yes - SMP50-200 meets GR-1089 Core First Level (2500 V, 500 A, 2/10 µs), ITU-T K20/K21 (6000 V, 150 A, 10/700 µs), and FCC Part 68 lightning surge requirements. Its UL497B listing (E136224) and documented performance in Table 1 confirm compliance without additional system-level testing.