Microchip Technology SMAJ110E3/TR13

Overview

SMAJ110E3/TR13 from Microsemi is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode designed for primary and secondary lightning surge protection in DC power rails and signal lines. It features a 110 V working peak standoff voltage (V_WM), 122 V minimum breakdown voltage (V_BR), clamps transients to ≤196 V at 5.2 A peak pulse current (I_PP), and delivers 500 W peak pulse power (10/1000 µs waveform). It is deployed in industrial power supplies, telecom interface circuits, and automotive body control modules.

For engineers reviewing the SMAJ110E3/TR13 datasheet, SMAJ110E3/TR13 pinout, SMAJ110E3/TR13 application, or SMAJ110E3/TR13 equivalent, key selection criteria include clamping voltage margin relative to protected IC V_MAX, IEC61000-4-5 Class 3 compliance with 42 Ω source impedance, RoHS-compliant matte-tin plating, and DO-214AC package thermal performance on FR4 with 1 oz copper.

Technical Context

This TVS operates as a unidirectional avalanche diode, triggered when reverse voltage exceeds V_BR = 122 V (min) at I_BR = 1 mA, entering low-impedance clamping mode within <100 ps. Its junction-to-lead thermal resistance is 15 °C/W, enabling sustained 5 W steady-state dissipation at 75 °C lead temperature.

The device meets IEC61000-4-2 (±8 kV contact ESD), IEC61000-4-4 (±2 kV EFT), and IEC61000-4-5 secondary lightning immunity up to Class 3 (42 Ω source) - confirmed for SMAJ110A per specification table - with clamping performance validated under 10/1000 µs exponential surge waveforms.

Key Specifications

Pinout & Package

DO-214AC (SMA) package with cathode-indicating band; void-free thermosetting epoxy case (UL94V-0), matte-tin-plated C-bend leads solderable per MIL-STD-750 Method 2026; weight: 0.064 g; moisture sensitivity level: Level 1 (no dry pack required).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ110A and SMBJ110A, SMAJ110E3/TR13 uniquely combines RoHS compliance, DO-214AC thermal efficiency (15 °C/W), and verified IEC61000-4-5 Class 3 immunity - making it optimal for new industrial and telecom designs requiring regulatory alignment and compact thermal management.

Availability

SMAJ110E3/TR13 is available at Aetrix Electronics and suitable for industrial power supplies, telecom interface protection, and automotive body control modules requiring stable component supply across extended temperature ranges and regulatory-compliant manufacturing.

Supply support for SMAJ110E3/TR13 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

Microsemi (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog and mixed-signal ICs, RF solutions, and discrete protection devices for aerospace, defense, and industrial markets.

The SMAJ series was engineered for surface-mount transient suppression in harsh-environment DC power systems, emphasizing fast response, repeatable clamping, and thermal robustness in compact DO-214AC packages.

FAQ

What is the clamping voltage of SMAJ110E3/TR13 at its rated peak pulse current?

The SMAJ110E3/TR13 clamps to a maximum of 196 V when subjected to its specified peak pulse current of 5.2 A under the standard 10/1000 µs waveform. This value is measured at the device terminals and defines the upper voltage limit imposed on protected circuitry during surge events. The clamping performance is guaranteed across the full operating temperature range of −65 °C to +150 °C.

Is SMAJ110E3/TR13 RoHS compliant and what does the "e3" suffix indicate?

Yes, SMAJ110E3/TR13 is RoHS compliant. The "e3" suffix explicitly denotes matte-tin plating per J-STD-002 and J-STD-020B Level 1 moisture sensitivity - eliminating lead-based terminations while maintaining solderability and thermal performance. This compliance is verified per EU Directive 2011/65/EU and is documented in Microsemi's official product specifications for the SMAJ5.0–170CA, e3 family.

Does SMAJ110E3/TR13 meet IEC61000-4-5 for lightning surge immunity?

Yes, SMAJ110E3/TR13 meets IEC61000-4-5 secondary lightning surge immunity up to Class 3 when tested with a 42 Ω source impedance, as confirmed in the manufacturer's specification table for the SMAJ110A variant (identical electrical characteristics). Its 500 W peak pulse rating and 196 V clamping voltage ensure reliable protection against 1 kV open-circuit / 23 A short-circuit surge events defined in this standard.

What is the thermal resistance and steady-state power rating of SMAJ110E3/TR13?

SMAJ110E3/TR13 has a junction-to-lead thermal resistance of 15 °C/W and delivers 5 W steady-state power dissipation when mounted on FR4 with 1 oz copper and the recommended pad layout. At ambient temperature (T_A = 25 °C), its derated steady-state power is 1.56 W. These values are measured per JEDEC standards and define safe continuous operation limits for thermal design.

How is the polarity marked on SMAJ110E3/TR13 and what does the "TR13" suffix mean?

SMAJ110E3/TR13 uses a cathode-indicating band on the body to denote polarity - the banded end is the cathode, connected to the protected line, while the unbanded end is the anode, tied to ground. The "TR13" suffix indicates tape-and-reel packaging on a 13-inch reel containing 2500 units, compliant with EIA-481-1-A standards for automated SMT assembly.