STMicroelectronics TPI8011N

Overview

TPI8011N 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) with balanced Tip–GND and Ring–GND paths. It enables robust surge suppression in differential- and common-mode transients while preserving high-speed data integrity.

For engineers reviewing the TPI8011N datasheet, TPI8011N pinout, TPI8011N application, or TPI8011N equivalent, key selection criteria include symmetrical bidirectional clamping, 4-point internal bonding architecture for L·di/dt suppression, SO-8 package thermal resistance (Rth(j-a) = 170 °C/W), and compliance with CCITT K17–K20, VDE 0433, and IEC 61000-4-2 Level 4 standards.

Technical Context

The TPI8011N implements a triple Trisil™ structure with matched silicon junctions across Tip–GND–Ring terminals, delivering identical breakdown behavior in both polarities and modes. Its "4-point" internal wire bonding eliminates parasitic inductance-induced overshoot during fast transients (e.g., 1.2/50 µs surges).

It operates as a voltage-triggered crowbar: below 80 V stand-off (VRM = 10 V), leakage remains ≤1 µA; at ≥80 V, it switches to low-impedance conduction with holding current IH ≤150 mA and forward drop VF < 3 V. Capacitance balance (|CA – CB| ≤30 pF) ensures longitudinal signal integrity on ISDN lines.

Key Specifications

Pinout & Package

Supplied in SO-8 package (JEDEC MS-012AC), with exposed thermal pad not electrically connected. Pins 2, 3, 6, and 7 are GND terminals; pins 1 and 8 connect to Tip; pins 4 and 5 connect to Ring - enabling true 4-point grounding for minimized ground loop inductance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPD2E001DRYR and PESD5V0S1BA,215, the TPI8011N uniquely delivers integrated tripolar crowbar action, matched 80 V breakdown in both modes, and 4-point GND architecture-making it the only solution qualified for ISDN U-interface primary surge protection per CCITT K17–K20.

Availability

TPI8011N is available at Aetrix Electronics and suitable for ISDN line card design, telecom gateway development, and DSL front-end protection requiring stable component supply and long-term lifecycle support.

Supply support for TPI8011N 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 TPI series belongs to ST's Telecom Protection portfolio, engineered specifically for symmetrical, high-reliability surge suppression in legacy and hybrid telephony interfaces including ISDN, xDSL, and T1/E1 lines.

FAQ

What is the maximum continuous operating voltage for TPI8011N?

The TPI8011N has a stand-off voltage (VRM) of 10 V, meaning it remains non-conductive under DC or AC voltages ≤10 V. It is designed for use on –48 V ISDN lines where the 10 V VRM ensures zero leakage during normal operation, while its 80 V VBR triggers only during overvoltage events.

Does TPI8011N require external current limiting?

No external current-limiting resistor is required for surge conduction, as the device self-limits via its intrinsic holding current (IH ≤150 mA). However, a series PTC or fuse is recommended upstream to prevent sustained fault currents in case of catastrophic line short after surge event.

How does the "4-point" bonding improve surge response?

The 4-point internal bonding connects Tip and Ring lines through separate bond wires to four dedicated GND pins, minimizing shared inductance. This eliminates L·di/dt voltage spikes during fast transients (<100 ns), ensuring the dynamic clamping voltage stays at 120 V even for 1.2/50 µs surges per VDE 0878.

Can TPI8011N be used in Ethernet or USB interfaces?

No - TPI8011N is optimized for ISDN's –48 V DC bias and 160 kbps signaling. Its 45 pF capacitance exceeds Ethernet (≤2 pF) and USB (≤5 pF) requirements, and its 80 V VBR is incompatible with 3.3 V/5 V logic rails. Use dedicated low-capacitance ESD arrays instead.