Semtech Corporation GS2985-INE3

Overview

GS2985-INE3 from Semtech is a Transient Diverting Suppressor (TDS) designed for high-energy EOS protection of 22V-rated power or I/O lines. It delivers ±30kV IEC 61000-4-2 ESD immunity, 40A peak pulse current (8/20μs), and a stable 27.5–28V clamping voltage across its full current and temperature range (−40°C to +125°C). It is used in USB Type-C PD bus protection where low, temperature-invariant clamping prevents damage to 20V-tolerant PD controllers.

For engineers reviewing the GS2985-INE3 datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage stability over temperature, dynamic resistance (<20 mΩ), junction capacitance (175 pF), and DFN 1.6×1.6mm 6-lead package compatibility with high-density USB and industrial PCB layouts.

Technical Context

The GS2985-INE3 uses a surge-rated FET as its primary protection element, activated by a precision trigger circuit when transient voltage exceeds breakdown. Unlike conventional TVS diodes, its clamping voltage remains nearly constant because the FET's R_DS(on) decreases with increasing current, minimizing V_C = V_BR + I_PP × R_DYN drift.

It operates across −40°C to +125°C with guaranteed 22V reverse stand-off voltage (V_RWM) and 25–27.9V reverse breakdown (V_BR at 1mA). Its 175 pF junction capacitance at 22V/1MHz and <600 nA leakage at V_RWM support robust signal integrity in DC-biased power-line applications.

Key Specifications

Pinout & Package

GS2985-INE3 is housed in a RoHS-compliant, halogen-free DFN 1.6 mm × 1.6 mm × 0.55 mm package with exposed thermal pad (not electrically connected). All six terminals are surface-mount; pins 1–3 are GND, pins 4–6 are IN. Proper layout requires connecting all three GND pins to a solid ground plane via multiple vias and routing all three IN pins in parallel to the protected line.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient suppression applications.

Compared with TDS2211P.C, GS2985-INE3 offers identical protection performance and mechanical fit but may differ in logistics coding; compared with uClamp2411ZA, GS2985-INE3 provides 67% higher surge current rating and 2.5V lower clamping-critical for safeguarding 22V power domains.

Availability

GS2985-INE3 is available at Aetrix Electronics and suitable for USB Type-C PD systems, industrial load switch inputs, and 22V IoT edge node power rails requiring stable component supply, long-term lifecycle assurance, and compliance with IEC 61000-4-2/4-4/4-5 standards.

Supply support for GS2985-INE3 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

Semtech Corporation is a U.S.-based fabless semiconductor company specializing in analog and mixed-signal ICs for precision sensing, protection, and signal integrity.

GS2985-INE3 belongs to Semtech's Transient Diverting Suppressor (TDS) product line, engineered specifically to replace conventional TVS diodes in high-reliability 20–24V power-rail protection applications demanding flat clamping and temperature stability.

FAQ

What is the primary function of the GS2985-INE3 in a circuit?

The GS2985-INE3 functions as a transient diverting suppressor for 22V power or I/O lines, using an active FET-based shunt architecture to clamp surges up to 40A (8/20μs) while maintaining a stable 27.5–28V clamping voltage. Unlike passive TVS diodes, GS2985-INE3 achieves this through dynamic R_DS(on) reduction, making it ideal for protecting USB PD controllers and industrial load switches where voltage margin is critical.

How does the GS2985-INE3 differ from standard TVS diodes in clamping behavior?

The GS2985-INE3 delivers nearly constant clamping voltage (27.5–28V) across its full 40A peak pulse current range and −40°C to +125°C operating temperature, whereas standard TVS diodes exhibit rising clamping voltage with both increasing current and temperature due to fixed dynamic resistance. This stability is achieved via a precision-triggered surge-rated FET, not a pn-junction, giving GS2985-INE3 superior predictability in harsh thermal environments.

What are the recommended PCB layout practices for the GS2985-INE3?

Place GS2985-INE3 as close as possible to the protected connector. Connect all three IN pins (4–6) in parallel to the protected line using a single short trace, and tie all three GND pins (1–3) directly to a solid ground plane using ≥3 vias. Avoid thermal pads-energy is dissipated internally-and ensure no sensitive traces run beneath or adjacent to the device to prevent coupling during fast ESD events.

Can the GS2985-INE3 be used on high-speed data lines like USB SuperSpeed differential pairs?

No, the GS2985-INE3 is not suitable for high-speed data lines. Its 175 pF junction capacitance would severely degrade signal integrity on USB 3.x or PCIe lanes. It is explicitly designed for 22V DC power rails or low-frequency I/O lines. For SuperSpeed protection, Semtech recommends low-capacitance devices like RClamp3371ZC (<0.25 pF), while GS2985-INE3 remains reserved for V_Bus and other power-domain applications.

What industry standards does the GS2985-INE3 meet for surge and ESD immunity?

The GS2985-INE3 meets IEC 61000-4-2 Level 4 (±30 kV contact/air), IEC 61000-4-4 Level 4 (±4 kV EFT), and IEC 61000-4-5 Level 4 (±1 kV, 42 Ω source) for unsymmetrical lines. Its 40A (8/20μs) rating satisfies common industrial surge requirements, and its 22V working voltage aligns with USB PD 3.0 specifications-making GS2985-INE3 compliant out-of-the-box for certified USB Type-C and industrial equipment designs.