My Inquiry
My Account
Microchip Technology SMAJ28E3/TR13
- Part No.:
- SMAJ28E3/TR13
- Manufacturer:
- Microchip Technology
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ28E3/TR13.pdf
- Description:
- TVS DIODE 28VWM 50VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:7,198
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMAJ28E3/TR13 from Microsemi is a unidirectional surface-mount transient voltage suppressor (TVS) designed for 28 V DC working voltage protection in power and signal lines. It delivers 500 W peak pulse power at 10/1000 µs, clamps transients to ≤50.0 V at 9.9 A peak pulse current, and features <100 ps response time. It is RoHS-compliant (e3 suffix), supplied in tape-and-reel (TR13), and used in industrial power supplies and automotive ECUs.
For engineers reviewing the SMAJ28E3/TR13 datasheet, SMAJ28E3/TR13 pinout, SMAJ28E3/TR13 application, or SMAJ28E3/TR13 equivalent, this page provides verified electrical parameters, IEC61000-4-2/4-4/4-5 compliance details, DO-214AC package mapping, and real-world design guidance for ESD, EFT, and secondary lightning surge protection.
Technical Context
The SMAJ28E3/TR13 operates as a unidirectional avalanche diode with a reverse standoff voltage (VWM) of 28 V and minimum breakdown voltage (VBR) of 31.1 V at 1 mA test current. Its clamping voltage (VC) is 50.0 V at 9.9 A peak pulse current (IPP), ensuring predictable overvoltage limiting during fast transients.
It meets IEC61000-4-2 (ESD ±8 kV contact), IEC61000-4-4 (EFT ±2 kV), and IEC61000-4-5 (secondary lightning, 42 Ω source: Class 3 up to 24 V, 12 Ω source: Class 2 up to 16 V). Thermal resistance is 15 °C/W junction-to-lead when mounted per recommended footprint.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 28 V - Maximum continuous reverse operating voltage before conduction begins. |
| VBR min @ IBR | 31.1 V @ 1 mA - Ensures reliable turn-on above normal operating voltage with margin. |
| VC @ IPP | 50.0 V @ 9.9 A - Limits downstream voltage to safe levels during 10/1000 µs surges. |
| PPP | 500 W - Sustains high-energy transients without failure under standard waveform. |
| ID @ VWM | 1 μA - Negligible leakage current preserves system efficiency and battery life. |
| tRESPONSE | <100 ps - Fast enough to protect CMOS, MCU I/O, and analog front-ends from ESD. |
| TOP/TSTG | –65 °C to +150 °C - Supports operation in harsh environments including engine bays and industrial controls. |
Pinout & Package
Package: DO-214AC (SMA), surface-mount, void-free thermosetting epoxy case with tin-lead or matte-tin plating; cathode indicated by band; weight 0.064 g; moisture sensitivity level (MSL) 1 - no dry pack required.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side connection to protected line | Connected to signal/power line requiring transient suppression; referenced to ground via PCB trace. |
| Cathode | High-side connection to ground reference | Marked by band; ties to system ground plane to shunt surge energy away from sensitive circuitry. |
Key Features
| Feature | Design Value |
|---|---|
| 500 W peak pulse power rating | Enables robust protection against high-energy switching transients and induced RF in 24 V industrial systems. |
| RoHS-compliant "e3" termination | Meets global environmental regulations without compromising solderability or thermal performance. |
| DO-214AC package with wide leads | Provides low thermal resistance (15 °C/W) and strong mechanical anchoring on FR4 PCBs. |
| IEC61000-4-5 Class 2 compliance (12 Ω source) | Validated for secondary lightning protection in automotive body control modules and CAN bus interfaces. |
| 100% screening option available (MA/MX prefixes) | Supports avionics-grade reliability with extended temperature cycling and HTRB testing. |
Applications
| Industrial Power Supply Protection | Automotive Body Control Module (BCM) |
|---|---|
Use Scenario: 24 V DC input stage of programmable logic controller (PLC) power supply exposed to load dump and relay coil flyback. IC Role / Device Role / Timing Role: Unidirectional TVS placed between input rail and chassis ground to clamp positive-going surges. Use Value: Clamps transients to ≤50.0 V, preventing damage to upstream rectifiers and downstream DC-DC controllers rated for 36 V max input. |
Use Scenario: LIN bus line in BCM subjected to ESD events and battery voltage transients during jump-start conditions. IC Role / Device Role / Timing Role: Standoff-rated TVS on LIN data line to suppress ESD (±8 kV) while maintaining signal integrity below 20 kHz. Use Value: Sub-100 ps response ensures clamping occurs before LIN transceiver input stages are overstressed, preserving communication uptime. |
| Telecom Remote Radio Unit (RRU) | Medical Diagnostic Imaging Interface |
Use Scenario: 28 V auxiliary power feed to remote radio unit in outdoor base station cabinet subject to induced lightning surges. IC Role / Device Role / Timing Role: Primary-level TVS on DC input before DC-DC conversion, coordinated with upstream GDT and downstream ceramic capacitor. Use Value: 500 W rating handles IEC61000-4-5 42 Ω Class 3 surges (up to 24 V VWM), enabling single-stage protection without derating. |
Use Scenario: Analog sensor interface board in MRI-compatible patient monitoring device requiring ultra-low leakage and ESD immunity. IC Role / Device Role / Timing Role: Low-leakage (1 μA) TVS on 28 V bias rail feeding precision op-amp front-end circuits. Use Value: Prevents false triggering or offset drift caused by ESD-induced latch-up, supporting IEC60601-1-2 compliance for medical EMC. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ28A | Same VWM, VBR, VC, and PPP; non-RoHS (SnPb) plating; no "e3" suffix. | Not suitable for RoHS-regulated end equipment; requires leaded solder process. | Select SMAJ28A only for legacy manufacturing or non-RoHS exempt applications. |
| SMBJ28A | Same VWM and VBR, but lower PPP = 600 W (10/1000 µs); SMB package (DO-214AA), slightly larger footprint. | Higher power handling but requires PCB layout change; not drop-in compatible. | Choose SMBJ28A only if system-level surge testing exceeds 500 W requirements and layout revision is feasible. |
Compared with SMAJ28E3/TR13, SMAJ28A lacks RoHS compliance and requires leaded assembly, while SMBJ28A offers higher surge rating but demands footprint redesign-making SMAJ28E3/TR13 the optimal balance of compliance, performance, and drop-in manufacturability for new 28 V designs.
Availability
SMAJ28E3/TR13 is available at Aetrix Electronics and suitable for industrial power supplies, automotive body control modules, telecom remote radio units, and medical diagnostic imaging interfaces requiring stable component supply across long production lifecycles.
Supply support for SMAJ28E3/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 components for aerospace, defense, and industrial markets.
The SMAJ series was developed specifically for surface-mount transient suppression in space-constrained, high-surge environments-emphasizing fast response, repeatable clamping, and rugged packaging for mission-critical power and interface protection.
FAQ
What is the maximum clamping voltage of SMAJ28E3/TR13 under standard 10/1000 µs surge conditions?
The SMAJ28E3/TR13 has a maximum clamping voltage (VC) of 50.0 V at 9.9 A peak pulse current (IPP) under the standardized 10/1000 µs double-exponential waveform. This value is guaranteed per Microsemi's MSC0270A Rev L datasheet and defines the upper voltage limit imposed on protected circuitry during surge events.
Is SMAJ28E3/TR13 RoHS-compliant and what does the "e3" suffix indicate?
Yes, SMAJ28E3/TR13 is RoHS-compliant-the "e3" suffix explicitly denotes annealed matte-tin plating per IPC/JEDEC standards, replacing traditional tin-lead terminations. This ensures full compliance with EU Directive 2011/65/EU and related global environmental regulations without sacrificing solderability or thermal performance.
Does SMAJ28E3/TR13 meet IEC61000-4-5 for secondary lightning protection?
Yes, SMAJ28E3/TR13 is validated for IEC61000-4-5 secondary lightning protection: it supports Class 2 with 12 Ω source impedance (up to 16 V VWM) and Class 3 with 42 Ω source impedance (up to 24 V VWM). While its VWM is 28 V, it remains effective for 24 V systems where Class 3 compliance is required.
What is the thermal resistance and recommended mounting for SMAJ28E3/TR13?
SMAJ28E3/TR13 has a junction-to-lead thermal resistance of 15 °C/W when mounted on FR4 with the recommended pad layout (per datasheet Page 5). For optimal heat dissipation, use minimum 1 oz copper, follow the specified DO-214AC footprint, and avoid thermal relief on cathode/anode pads to maintain low-impedance surge paths to ground.
Can SMAJ28E3/TR13 be used in bidirectional configurations?
No-SMAJ28E3/TR13 is unidirectional only. Bidirectional variants require a "C" or "CA" suffix (e.g., SMAJ28CA). The "E3" and absence of "C/CA" confirm its unidirectional polarity, with cathode marked by a band. Using it in bidirectional applications would result in forward conduction during negative transients and potential failure.
SMAJ28E3/TR13 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Package/Case:
- DO-214AC, SMA
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 28V
- Voltage - Breakdown (Min):
- 31.1V
- Voltage - Clamping (Max) @ Ipp:
- 50V
- Current - Peak Pulse (10/1000µs):
- 9.9A
- Power - Peak Pulse:
- 500W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC (SMA)
SMAJ28E3/TR13 FAQ
1.How can I place an order for SMAJ28E3/TR13 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ28E3/TR13 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for SMAJ28E3/TR13 reliable?
The price and inventory of SMAJ28E3/TR13 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ28E3/TR13 is usually 5 days.
3.What payment methods are accepted for SMAJ28E3/TR13?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ28E3/TR13 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ28E3/TR13?
SMAJ28E3/TR13 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ28E3/TR13 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for SMAJ28E3/TR13?
For technical support, including SMAJ28E3/TR13 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ28E3/TR13 requirements.
6.How does Aetrix verify that SMAJ28E3/TR13 is sourced from the original manufacturer or authorized distributors?
All SMAJ28E3/TR13 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that SMAJ28E3/TR13 meets industry standards.
7.What is the process for return or replacement of SMAJ28E3/TR13?
All SMAJ28E3/TR13 units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ28E3/TR13, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The SMAJ28E3/TR13 part is unused and in its original packaging.
Return procedure for SMAJ28E3/TR13:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ28E3/TR13 Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
-
D5V0L1B2WS-7
Diodes Incorporated
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
