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Microchip Technology SMAJ51E3/TR13
- Part No.:
- SMAJ51E3/TR13
- Manufacturer:
- Microchip Technology
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ51E3/TR13.pdf
- Description:
- TVS DIODE 51VWM 91.1VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:5,418
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Product details
Overview
SMAJ51E3/TR13 from Microsemi is a unidirectional surface-mount Transient Voltage Suppressor (TVS) in DO-214AC (SMA) package, rated for 500 W peak pulse power at 10/1000 µs, with 51 V standoff voltage (VWM), 56.7 V minimum breakdown voltage (VBR), and 91.1 V maximum clamping voltage (VC) at 5.5 A peak pulse current - deployed for ESD/EFT protection in power supply input stages and industrial I/O interfaces.
For engineers reviewing the SMAJ51E3/TR13 datasheet, SMAJ51E3/TR13 pinout, SMAJ51E3/TR13 application, or SMAJ51E3/TR13 equivalent, this part delivers verified IEC 61000-4-2 Level 4 (±15 kV contact), IEC 61000-4-4 (4 kV EFT), and secondary lightning protection per IEC 61000-4-5 (Class 2, 42 Ω source) - critical for robust front-end surge immunity in automotive body electronics and telecom power rails.
Technical Context
This unidirectional TVS diode operates as a voltage-clamped shunt protector: when reverse voltage exceeds VBR (56.7 V min), it avalanches into low-impedance conduction within <100 ps, limiting transient energy to ≤91.1 V at 5.5 A while dissipating up to 500 W for 10/1000 µs pulses. Its thermal resistance is 15 °C/W junction-to-lead, enabling reliable operation at -65 °C to +150 °C ambient.
The device features RoHS-compliant matte-tin plating, C-bend leads per MIL-STD-750 Method 2026, and moisture sensitivity level 1 (no dry pack required). It is supplied in 12 mm tape & reel (750 pcs/reel), marked "51Ae3" on the cathode-banded body, and designed for solder reflow at 260 °C for 10 s max.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 51 V - maximum continuous reverse operating voltage before clamping begins; sets safe DC bias margin for 48 V systems. |
| VBR min @ IBR | 56.7 V @ 1 mA - guaranteed avalanche onset threshold; ensures predictable turn-on above nominal rail. |
| VC @ IPP | 91.1 V @ 5.5 A - clamping voltage under 10/1000 µs surge; defines worst-case stress on downstream ICs. |
| PPP | 500 W - peak pulse power rating; supports high-energy transients like inductive switch-off or lightning-induced surges. |
| ID @ VWM | 5.5 µA - leakage current at 51 V; negligible loading on 48 V supply rails during normal operation. |
| tclamp | <100 ps - theoretical response time; enables effective suppression of ESD events (IEC 61000-4-2) before damage occurs. |
| TJ range | -65 °C to +150 °C - full operational temperature envelope; validated for under-hood automotive and industrial environments. |
Pinout & Package
Package: DO-214AC (SMA), surface-mount, void-free thermosetting epoxy case meeting UL94V-0; cathode indicated by band on body; weight 0.064 g; JEDEC-compliant footprint with recommended pad layout per datasheet page 5.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side connection to protected circuit ground | Provides return path for surge current; must be routed with minimal inductance to earth/chassis ground. |
| Cathode | High-side connection to protected line (e.g., VIN) | Connected to input rail; clamps transients to ground when voltage exceeds VBR; polarity-sensitive installation. |
Key Features
| Feature | Design Value |
|---|---|
| 500 W peak pulse power | Enables single-device protection against high-energy transients (e.g., ISO 7637-2 Pulse 1/2a/5a) without parallel stacking. |
| RoHS-compliant "e3" suffix | Meets EU RoHS Directive 2011/65/EU with annealed matte-tin plating; no lead or hazardous substance restrictions impact reliability. |
| IEC 61000-4-5 Class 2 compliance | Validated for secondary lightning surges (1 kV open-circuit, 42 Ω source) - suitable for industrial Ethernet ports and PLC analog inputs. |
| Moisture sensitivity Level 1 | Eliminates bake-out requirement prior to reflow; reduces manufacturing cost and avoids thermal stress on PCB assemblies. |
| Unidirectional configuration | Optimized for DC-biased lines (e.g., 48 V telecom supplies); provides lower clamping than bidirectional equivalents at same VWM. |
Applications
| Industrial Power Input Protection | Automotive Body Control Module (BCM) |
|---|---|
Use Scenario: 48 V DC input stage of programmable logic controller (PLC) power supply exposed to load dump and inductive switching noise. IC Role / Device Role: Primary shunt TVS placed between VIN and GND, upstream of DC-DC converter input capacitor. Use Value: Clamps 500 W transients to ≤91.1 V, preventing overvoltage failure of buck controller ICs and maintaining system uptime per IEC 61000-4-5 Class 2. |
Use Scenario: LIN bus transceiver power rail (VBAT) in door module subjected to ESD and battery reversal transients. IC Role / Device Role: Unidirectional TVS connected anode-to-ground, cathode-to-VBAT, protecting transceiver's internal LDO and driver stages. Use Value: Sub-100 ps response suppresses ±15 kV contact ESD (IEC 61000-4-2) before transceiver latch-up, preserving communication integrity. |
| Telecom DC Power Feeding | Industrial Ethernet PHY Interface |
Use Scenario: -48 V DC feed line in remote radio head (RRH) powered via PoE-like infrastructure with induced lightning surges. IC Role / Device Role: Bidirectional-capable design (though SMAJ51E3/TR13 is unidirectional, used in pair or with complementary device) for negative-rail clamping. Use Value: Withstood 1 kV/42 Ω IEC 61000-4-5 surge without degradation, ensuring uninterrupted RF signal processing during storm events. |
Use Scenario: 3.3 V auxiliary supply rail feeding Ethernet PHY IC in factory automation switch, exposed to EFT bursts on adjacent traces. IC Role / Device Role: Local TVS mounted directly at PHY VDD pin to suppress coupled fast transients from data lines or relay switching. Use Value: 5.5 µA standby leakage avoids loading sensitive LDO output; 91.1 V clamping irrelevant here but confirms robustness margin for 3.3 V rail with external series impedance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ51A-E3/5A (Vishay) | Identical VWM (51 V), VBR (56.7 V min), VC (91.1 V), and PPP (500 W); same DO-214AC package and RoHS compliance. | No functional deviation; validated for identical IEC 61000-4-2/4-4/4-5 test profiles. | Select when dual-sourcing is required; pin-to-pin and performance drop-in replacement with identical thermal and layout behavior. |
| 1.5SMC51A (ON Semiconductor) | Same VWM (51 V) and VC (91.1 V), but higher VBR (56.7–62.7 V typ), 1500 W PPP, and larger DO-214AB (SMC) package (7.11 × 6.22 mm vs. SMAJ's 4.57 × 2.79 mm). | Higher surge capacity suits higher-risk zones (e.g., outdoor cabinet mains entry), but requires PCB footprint redesign. | Choose for enhanced surge margin where board space allows; not a direct layout replacement due to larger SMC outline. |
Compared with SMAJ51E3/TR13, SMAJ51A-E3/5A offers identical electrical and mechanical specs for seamless second-source use, while 1.5SMC51A trades compactness for higher 1500 W surge handling - requiring footprint revision but delivering extended lifetime in high-stress field deployments.
Availability
SMAJ51E3/TR13 is available at Aetrix Electronics and suitable for industrial power input protection, automotive body control modules, telecom DC feeding, and industrial Ethernet PHY interface applications requiring stable component supply, consistent RoHS compliance, and verified IEC 61000-4-5 Class 2 surge immunity.
Supply support for SMAJ51E3/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 engineered for surface-mount transient suppression in space-constrained, high-surge environments - targeting automotive, industrial control, and telecom infrastructure where DO-214AC footprint and 500 W capability balance density and ruggedness.
FAQ
What is the clamping voltage of SMAJ51E3/TR13 at its rated peak pulse current?
The SMAJ51E3/TR13 has a maximum clamping voltage (VC) of 91.1 V at 5.5 A peak pulse current (IPP) under the standard 10/1000 µs waveform. This value defines the upper voltage limit imposed on protected circuitry during surge events and is measured per Figure 2 in the Microsemi datasheet MSC0270A Rev L. The SMAJ51E3/TR13 maintains this clamping performance across its full operating temperature range.
Is SMAJ51E3/TR13 unidirectional or bidirectional, and how is polarity identified?
SMAJ51E3/TR13 is a unidirectional TVS diode, meaning it conducts only in reverse breakdown (cathode positive relative to anode). Polarity is marked by a visible cathode band on the device body; the anode is the unmarked end. This configuration is intended for DC-biased lines like 48 V power rails. Bidirectional variants use a "C" or "CA" suffix (e.g., SMAJ51CA), which SMAJ51E3/TR13 does not carry.
Does SMAJ51E3/TR13 meet IEC 61000-4-5 for lightning surge immunity?
Yes, SMAJ51E3/TR13 is certified for secondary lightning surge immunity per IEC 61000-4-5 with 42 Ω source impedance at Class 2 level (1 kV open-circuit voltage). This validation applies specifically to the SMAJ5.0–SMAJ51A series as stated in the Microsemi datasheet. The device clamps such surges to ≤91.1 V, protecting downstream components without degradation when properly mounted with low-inductance grounding.
What is the maximum steady-state power dissipation of SMAJ51E3/TR13 on a standard FR4 PCB?
When mounted on a standard FR4 printed circuit board with 1 oz copper and the recommended footprint, SMAJ51E3/TR13 has a steady-state power dissipation rating of 1.56 W at 25 °C ambient temperature (TA) and 5 W at 75 °C lead temperature (TL). These values reflect thermal limits under continuous DC bias and are distinct from its 500 W peak pulse rating, which applies only to short-duration transients.
How is SMAJ51E3/TR13 packaged and marked for automated assembly?
SMAJ51E3/TR13 is supplied in EIA-481-1-A compliant 12 mm carrier tape on 7-inch reels (750 units/reel), designated by the "TR13" suffix. The device body is marked "51Ae3" - indicating 51 V standoff, unidirectional "A" variant, and RoHS-compliant "e3" plating - with cathode polarity shown by a single band. Lead finish is annealed matte tin, qualified for standard Pb-free reflow profiles up to 260 °C for 10 seconds.
SMAJ51E3/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):
- 51V
- Voltage - Breakdown (Min):
- 56.7V
- Voltage - Clamping (Max) @ Ipp:
- 91.1V
- Current - Peak Pulse (10/1000µs):
- 5.5A
- 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)
SMAJ51E3/TR13 FAQ
1.How can I place an order for SMAJ51E3/TR13 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ51E3/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 SMAJ51E3/TR13 reliable?
The price and inventory of SMAJ51E3/TR13 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ51E3/TR13 is usually 5 days.
3.What payment methods are accepted for SMAJ51E3/TR13?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ51E3/TR13 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ51E3/TR13?
SMAJ51E3/TR13 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ51E3/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 SMAJ51E3/TR13?
For technical support, including SMAJ51E3/TR13 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ51E3/TR13 requirements.
6.How does Aetrix verify that SMAJ51E3/TR13 is sourced from the original manufacturer or authorized distributors?
All SMAJ51E3/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 SMAJ51E3/TR13 meets industry standards.
7.What is the process for return or replacement of SMAJ51E3/TR13?
All SMAJ51E3/TR13 units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ51E3/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 SMAJ51E3/TR13 part is unused and in its original packaging.
Return procedure for SMAJ51E3/TR13:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ51E3/TR13 Tags
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