Semtech Corporation 1N5551

Overview

TDS2211P from Semtech is a transient diverting suppressor designed for high-energy EOS protection on 22V voltage buses or I/O lines, featuring ±30kV IEC 61000-4-2 ESD immunity, 40A peak pulse current (8/20μs), and stable 27.5–28V clamping across temperature and current range; it protects USB Type-C power delivery lines, load switch inputs, and industrial I/O interfaces.

For engineers reviewing the TDS2211P datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage stability under 40A surge, DFN-6 thermal and layout performance, 175pF junction capacitance at 22V, and compatibility with 22V working voltage systems requiring robust EOS resilience beyond standard TVS diodes.

Technical Context

The TDS2211P uses a surge-rated FET as its primary protection element, activated by a precision trigger circuit that turns on the shunt FET when transient voltage exceeds the breakdown threshold. Unlike conventional TVS diodes, its clamping voltage remains nearly constant due to low R_DS(on) (<0.1Ω) and dynamic resistance of only 20mΩ.

It operates over –40°C to +125°C, maintains ≤600nA reverse leakage at 22V, and delivers stable 27.5–28V clamping at both 24A and 40A (1.2/50μs + 8/20μs combination waveform, R_S = 2Ω), with no degradation in clamping performance up to 125°C.

Key Specifications

Pinout & Package

Package: DFN-6 (1.6mm × 1.6mm × 0.55mm), Pb-free, RoHS-compliant, UL 94V-0 molding compound, marked "T22" with date code.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ22A and TPD2E007DRYR, the TDS2211P uniquely combines 40A surge rating, 27.5–28V flat clamping, and DFN-6 footprint - making it the only option for compact, thermally stable 22V bus protection meeting IEC 61000-4-5 Level 4 without layout compromises.

Availability

TDS2211P is available at Aetrix Electronics and suitable for USB Type-C power delivery designs, industrial load switch inputs, and IoT 22V rail protection requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TDS2211P 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 connectivity.

The TDS product line delivers transient diverting suppressors using FET-based architecture to overcome clamping voltage drift and thermal limitations of traditional TVS diodes - targeting high-reliability 12–48V industrial, computing, and USB-C infrastructure.

FAQ

What is the maximum operating temperature for the TDS2211P?

The TDS2211P is rated for continuous operation from –40°C to +125°C ambient temperature. Its clamping voltage remains stable across this full range, with no increase in V_C at elevated temperatures - unlike conventional TVS diodes whose clamping rises significantly above 85°C. This makes the TDS2211P especially suitable for enclosed industrial environments where thermal management is limited.

Does the TDS2211P require a thermal pad on the PCB?

No, the TDS2211P does not require a thermal pad. Its FET-based architecture dissipates surge energy in the channel rather than the junction, eliminating localized heating concerns that necessitate thermal pads in traditional TVS devices. The datasheet explicitly states "no thermal pad is needed," and recommends instead multiple vias from GND pins (1–3) to an internal ground plane to minimize inductance.

Can the TDS2211P replace a standard TVS diode like SMAJ22A in an existing design?

The TDS2211P can replace SMAJ22A in 22V rail protection applications, but only after verifying PCB layout and grounding. While both share the same 22V working voltage, the TDS2211P requires all six pins (three GND, three IN) to be properly connected - unlike the two-terminal SMAJ22A. Layout changes are mandatory to accommodate the DFN-6 footprint and multi-pin routing, and the lower clamping voltage (28V vs. 38V) may require revalidation of downstream component margins.

What is the significance of the 20mΩ dynamic resistance specification for the TDS2211P?

The 20mΩ dynamic resistance (R_DYN) reflects the effective on-resistance of the internal shunt FET under surge conditions. This ultra-low value ensures minimal voltage rise (ΔV = I_PP × R_DYN) as surge current increases - resulting in the flat 27.5–28V clamping curve across 1–40A. It directly enables the TDS2211P's key advantage over TVS diodes, whose R_DYN is fixed and much higher (typically >1Ω), causing linear V_C escalation with current.

Is the TDS2211P suitable for protecting high-speed data lines such as USB 3.2 or PCIe?

No, the TDS2211P is not suitable for high-speed data lines. Its 175pF junction capacitance at 22V is optimized for power rail and low-frequency I/O protection, not signal integrity preservation. For USB 3.2, PCIe, or DisplayPort lines, Semtech recommends low-capacitance ESD protectors like RClamp3371ZC (<0.25pF). Using the TDS2211P on such lines would cause severe signal attenuation and eye diagram closure.