STMicroelectronics ETP01-2821RL

Overview

ETP01-2821RL from STMicroelectronics is a low-capacitance transient voltage suppressor (TVS) array using Trisil™ technology for Ethernet line protection. It provides differential and common-mode surge suppression with 28 V breakdown voltage, 13 pF max capacitance at 0 V, 150 A peak pulse current (2/10 µs), and SO-8 package compliance with Telcordia GR-1089 and ITU-T K20/21 standards. It is deployed in 10/100 Mbps Ethernet physical layer interfaces to safeguard transceivers against lightning-induced surges.

For engineers reviewing the ETP01-2821RL datasheet, ETP01-2821RL pinout, ETP01-2821RL application, or ETP01-2821RL equivalent, this device delivers fail-safe short-circuit protection with stable clamping performance across temperature, minimal signal distortion due to ultra-low capacitance, and verified compliance with IEC 61000-4-2/4-4/4-5 and MIL-STD-883E HBM.

Technical Context

The ETP01-2821RL integrates four bidirectional Trisil-based protection elements in a single SO-8 package, configured as two independent differential pairs (T1–GND–T2 per channel). Its planar silicon structure enables simultaneous high surge handling (100 A @ 8/20 µs) and low junction capacitance (≤13 pF between I/O and GND).

It operates in voltage-triggered avalanche mode with precise 28 V (min) / 36 V (max) breakdown, 1 mA holding current, and 30 V maximum clamping voltage at 100 A. The device sustains non-repetitive surge currents up to 8 A for 20 ms without degradation, supporting robust front-end protection in telecom line cards.

Key Specifications

Pinout & Package

ETP01-2821RL uses a JEDEC-registered SO-8 surface-mount package with gull-wing leads, UL94 V0 epoxy, and lead-free construction. Pin 1 is marked by a beveled corner and dot; the device is symmetrically arranged for dual-channel Ethernet line protection.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Ethernet line protection applications.

Compared with SP1002-01FTG and SRV05-4, ETP01-2821RL uniquely combines 28 V breakdown for 100BASE-TX compatibility, fail-safe Trisil reliability, and full Telcordia/ITU-T certification-making it the only choice for carrier-grade Ethernet hardware requiring long-term field stability.

Availability

ETP01-2821RL is available at Aetrix Electronics and suitable for 10/100 Mbps Ethernet interfaces, T1/E1 line cards, and industrial gateway designs requiring stable component supply, long-lifecycle support, and certified surge immunity.

Supply support for ETP01-2821RL 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, digital, and mixed-signal ICs for automotive, industrial, and communications markets.

The ETP01 series belongs to ST's Transient Voltage Suppressor portfolio, engineered specifically for high-speed data line protection in telecom infrastructure where signal fidelity and multi-standard surge compliance are non-negotiable.

FAQ

What is the failure mode of ETP01-2821RL under end-of-life surge stress?

The ETP01-2821RL employs Trisil™ technology that guarantees a fail-safe short-circuit mode upon catastrophic surge overload. Unlike standard TVS diodes that may degrade into high-impedance open circuits, this device maintains low-resistance conduction, preserving downstream circuit protection even after exceeding its rated surge lifetime-critical for telecom central office reliability.

Can ETP01-2821RL protect both differential and common-mode transients on Ethernet lines?

Yes. Its internal configuration supports simultaneous differential-mode clamping (between T1 and T2 pins of each channel) and common-mode suppression (between I/O pairs and shared GND terminals). This dual-path capability meets Telcordia GR-1089 Intrabuilding requirements for metallic and longitudinal surge tests without external components.

Is the 13 pF capacitance measured between I/O and GND or I/O and I/O?

The 13 pF maximum capacitance is specified between each I/O pin (T1 or T2) and GND under 0 V bias, 1 MHz, and 1 V RMS test conditions. This value directly impacts signal integrity on individual Ethernet lanes. Capacitance between I/O pins (T1–T2) is not published but is inherently lower due to device topology.

Does ETP01-2821RL require external current-limiting resistors in series with Ethernet lines?

No. The device is designed for direct placement between magnetics and PHY without series impedance. Its low dynamic resistance (<1 Ω during clamping) and fast response time (<1 ns) enable effective energy diversion without compromising 100BASE-TX timing budgets or introducing insertion loss beyond acceptable limits.