STMicroelectronics TPI8011NRL

Overview

TPI8011NRL from STMicroelectronics is a bidirectional tripolar crowbar protection device for ISDN U-interface and S-interface telecom line protection, featuring 80 V breakdown voltage (VBR), 120 V dynamic breakover voltage (VBO dyn.), 30 A peak pulse current (10/1000 µs), and low capacitance (≤45 pF) optimized for high-speed data integrity. It is implemented in SO-8 package with 4-point internal bonding to suppress L·di/dt overvoltage during fast transients.

For engineers reviewing the TPI8011NRL datasheet, TPI8011NRL pinout, TPI8011NRL application, or TPI8011NRL equivalent, key selection criteria include common-mode/differential-mode symmetrical clamping, longitudinal capacitance balance (CA–CB ≤30 pF), fixed VBR tolerance (70–80 V), and compliance with CCITT K17–K20, VDE 0433, and IEC 61000-4-2 level 4 surge standards.

Technical Context

The TPI8011NRL integrates three monolithically matched Trisil™-based crowbar elements in a single SO-8 package, enabling simultaneous protection of Tip, Ring, and GND lines in bipolar telecom interfaces. Its symmetrical structure ensures identical VBR (±5% tolerance) and IPP capability (30 A, 10/1000 µs) in both polarities and both common- and differential-mode surge paths.

Internal "4-point" wire bonding decouples surge current return paths to minimize parasitic inductance-induced overshoot during sub-microsecond transients. Capacitance asymmetry is actively controlled (CA/CB ≤45/15 pF, Δ ≤30 pF) to preserve longitudinal balance critical for ISDN echo cancellation and bit-error-rate performance.

Key Specifications

Pinout & Package

Package: SO-8, surface-mount, lead-free (ECOPACK®), UL94 V0 epoxy, 1.27 mm pitch, 4.9 mm × 6.0 mm body size.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPI12011NRL, the TPI8011NRL offers tighter clamping (120 V vs. 170 V) for standard ISDN line voltages, while PESD5V0S1BA serves only ESD-level threats and cannot handle 30 A surges - making it complementary, not substitutable.

Availability

TPI8011NRL is available at Aetrix Electronics and suitable for ISDN interface protection, DSL line card design, and VoIP gateway analog port hardening requiring stable component supply, long-lifecycle support, and traceable ECOPACK® sourcing.

Supply support for TPI8011NRL 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 silicon solutions for automotive, industrial, and communications markets since 1987.

The TPI series belongs to ST's dedicated telecom protection product line, engineered specifically for symmetrical, low-capacitance crowbar protection of ISDN, DSL, and analog telephony interfaces - prioritizing longitudinal balance and fast transient immunity over generic TVS performance.

FAQ

What is the recommended PCB layout for TPI8011NRL to achieve optimal surge performance?

ST specifies a crossing layout: Tip (Pin 1) and Ring (Pin 8) traces must physically cross over the device body, with all four GND pins (2, 3, 6, 7) connected to a solid ground plane using multiple vias. This implements the "4-point" bonding benefit by minimizing loop inductance. NC pins (4, 5) should be grounded or left floating per layout density constraints - no internal connection exists.

Does TPI8011NRL require external hold-off circuitry or series impedance?

No. The TPI8011NRL is a self-holding crowbar device with 150 mA typical holding current (IH). It latches ON during surge and resets only when line current falls below IH - naturally achieved when the surge decays or the line is disconnected. No external resistor or timing circuit is needed, unlike discrete SCR-based protectors.

How does TPI8011NRL differ from standard bidirectional TVS diodes in ISDN applications?

Unlike TVS diodes, the TPI8011NRL uses Trisil™ thyristor technology to provide lower dynamic clamping (120 V vs. typical 150+ V for TVS), matched differential/common-mode response, and inherent crowbar action that sinks high surge current without thermal runaway. Its 45 pF capacitance is also tightly balanced - critical for ISDN echo cancellation where TVS asymmetry causes return loss degradation.

Is TPI8011NRL compliant with RoHS and REACH regulations?

Yes. TPI8011NRL is manufactured in ST's ECOPACK®-compliant SO-8 package with lead-free second-level interconnects, fully compliant with EU RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006. The "ECOPACK" marking appears on the package and inner box label per JEDEC JESD97.