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onsemi SA28ARL
- Part No.:
- SA28ARL
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-204AC, DO-15, Axial
- Datasheet:
-
SA28ARL.pdf
- Description:
- TVS DIODE 28VWM 45.4VC AXIAL
- Quantity:
- Payment:
- Shipping:
Inventory:3,922
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Product details
Overview
SA28ARL from onsemi is a unidirectional 500 W peak power MiniMOSORB Zener transient voltage suppressor (TVS) designed for clamping high-energy transients in DC power rails and signal lines. It features a 28 V working peak reverse voltage (VRWM), 45.4 V maximum clamping voltage at 31 A peak pulse current, <1 µA leakage at VRWM, and sub-1 ns response time. It is used in industrial power supplies and medical equipment for robust overvoltage protection.
For engineers reviewing the SA28ARL datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage margin relative to system operating voltage, surge current capability under 1 ms pulses, UL 497B certification for isolated loop protection, and axial leaded Surmetic package compatibility with through-hole assembly processes.
Technical Context
The SA28ARL operates as a unidirectional Zener-based TVS diode, conducting only during reverse overvoltage events above its breakdown threshold. Its clamping action relies on avalanche breakdown at a nominal 32.75 V (VBR @ IT = 1 mA), with tight tolerance (min 31.1 V, max 34.4 V) and low dynamic impedance to limit transient overshoot.
It is rated for 500 W nonrepetitive peak pulse power per 1 ms waveform (Figure 4), derated linearly above 25°C ambient, and supports steady-state dissipation up to 3.0 W at TL ≤ 75°C. Thermal resistance from junction to lead is 33.3°C/W, enabling reliable heat transfer in leaded axial mounting configurations.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 28 V - Maximum continuous reverse operating voltage before clamping begins; sets minimum system rail margin. |
| VBR @ IT=1 mA | 31.1–34.4 V - Tight breakdown range ensures predictable turn-on; critical for precise overvoltage thresholding. |
| VC @ IPP=31 A | 45.4 V - Clamping voltage under full-rated surge; defines worst-case voltage seen by protected circuitry. |
| IPP | 31 A - Peak pulse current capacity at 1 ms; determines survivability against IEC 61000-4-5 Level 4 surges. |
| Leakage @ VRWM | <1 µA - Negligible standby power loss and minimal loading on sensitive reference or control nodes. |
| Response Time | <1 ns - Fast enough to suppress ESD and lightning-induced fast transients before IC damage occurs. |
| UL 497B | Certified - Validated for isolated loop circuit protection in telecom and industrial interfaces per safety standard. |
Pinout & Package
SA28ARL is housed in an axial-leaded Surmetic plastic package (Case 59AA), with cathode indicated by a polarity band. Leads are tin-plated, solderable, and rated for 260°C for 10 seconds at 1/16 inch from case.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal | Connected to lower-potential side (e.g., ground or return path); completes conduction path during reverse transient. |
| Cathode | Avalanche breakdown terminal | Connected to protected line; voltage referenced to anode; polarity band identifies this terminal for correct PCB orientation. |
Key Features
| Feature | Design Value |
|---|---|
| 500 W peak pulse power | Withstands 1 ms transients up to 31 A without degradation-sufficient for IEC 61000-4-5 combination wave testing. |
| UL 497B recognition | Validated for use in safety-critical isolated loop circuits including telecom interfaces and process control signal conditioning. |
| ESD rating >16 kV HBM | Provides intrinsic board-level ESD immunity without requiring additional discrete protection on downstream IC pins. |
| Low zener impedance | Ensures stable clamping voltage across varying surge currents-critical for protecting voltage-tolerant ICs like microcontrollers and ADCs. |
| Pb-Free Surmetic package | RoHS-compliant axial lead construction with corrosion-resistant finish and proven long-term solder joint reliability. |
Applications
| Industrial Power Supply Protection | Medical Equipment Input Stage |
|---|---|
Use Scenario: Protecting 24 V DC input rails in programmable logic controllers (PLCs) against load dump and inductive switching transients. IC Role / Device Role / Timing Role: Standoff TVS diode placed between input rail and chassis ground to clamp surges before they reach DC-DC converters and supervisors. Use Value: 45.4 V clamping ensures safe margin below 60 V absolute maximum ratings of common industrial PMICs and gate drivers. | Use Scenario: Safeguarding analog front-end inputs of patient monitoring devices connected to external sensors or leads. IC Role / Device Role / Timing Role: Primary transient suppressor on isolated sensor interface lines compliant with IEC 60601-1 creepage/clearance requirements. Use Value: UL 497B certification confirms suitability for medically isolated circuits where failure could compromise patient safety. |
| Process Control Signal Conditioning | Business Machine Power Sequencing |
Use Scenario: Shielding 4–20 mA current loop receivers in factory automation systems from field wiring induced surges. IC Role / Device Role / Timing Role: Unidirectional TVS mounted across loop receiver terminals to shunt transients while preserving loop integrity. Use Value: Sub-1 µA leakage avoids disturbing precision current measurement accuracy; 28 V VRWM matches typical loop supply headroom. | Use Scenario: Securing 12 V auxiliary rails in multifunction printers and copiers during hot-plug events and relay bounce. IC Role / Device Role / Timing Role: Secondary-level TVS on internal DC distribution net to prevent latch-up in ASICs and motor drivers. Use Value: 500 W peak rating handles repetitive switching surges without thermal runaway; axial package fits legacy through-hole layouts. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ28A | Surface-mount SMA package (vs. axial); same VRWM and VC, but lower IPP (26.7 A vs. 31 A). | Requires SMT reflow process; unsuitable for through-hole legacy designs or high-vibration environments needing mechanical retention. | Select when board space is constrained and automated assembly is available; verify layout clearance for 26.7 A surge handling. |
| P6SMB28A | Same axial DO-204AC package; identical VRWM and VBR range, but higher VC (48.4 V) and lower IPP (25.1 A). | Marginally higher clamping voltage reduces protection level for 3.3 V or 5 V logic; acceptable for 24 V systems with wider tolerances. | Choose for cost-sensitive volume production where 48.4 V clamping remains within protected IC limits. |
Compared with SMAJ28A and P6SMB28A, SA28ARL delivers the highest surge current capacity (31 A) in an axial package with the lowest clamping voltage (45.4 V), making it optimal for demanding industrial and medical applications requiring both mechanical robustness and tight voltage limiting.
Availability
SA28ARL is available at Aetrix Electronics and suitable for industrial power supplies, medical equipment, and process control systems requiring stable component supply and long-term manufacturability.
Supply support for SA28ARL 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
onsemi (formerly ON Semiconductor) is a global semiconductor manufacturer specializing in energy-efficient power, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The SA5.0A Series-including SA28ARL-is part of onsemi's MiniMOSORB transient voltage suppressor family, engineered specifically for high-reliability overvoltage protection in harsh industrial and safety-critical environments.
FAQ
What is the clamping voltage of SA28ARL at its rated peak pulse current?
The SA28ARL has a maximum clamping voltage (VC) of 45.4 V at its rated peak pulse current (IPP) of 31 A, measured using the 1 ms exponential waveform defined in Figure 4 of the datasheet. This value represents the worst-case voltage imposed on protected circuitry during a full-rated surge event, and is critical for verifying margin against downstream IC absolute maximum ratings. The SA28ARL maintains this performance consistently due to its low zener impedance and thermally optimized Surmetic package.
Is SA28ARL certified for safety-critical isolation applications?
Yes, SA28ARL carries UL 497B recognition (File #E116110) for isolated loop circuit protection, covering the entire SA5.0A–SA170A series. This certification validates compliance with dielectric withstand, endurance conditioning, and strike voltage breakdown tests required for use in telecom interfaces, medical sensor isolation barriers, and industrial fieldbus networks. The SA28ARL meets these requirements as shipped in its Pb-Free Surmetic axial package.
What is the breakdown voltage range of SA28ARL at 1 mA test current?
The SA28ARL exhibits a breakdown voltage (VBR) range of 31.1 V (minimum) to 34.4 V (maximum) at IT = 1 mA and TA = 25°C, with a nominal value of 32.75 V. This tight tolerance ensures consistent turn-on behavior across production lots and supports reliable design margining in 24 V systems. The SA28ARL's specified temperature coefficient further guarantees stability across its -55°C to +175°C operating range.
Can SA28ARL be used in bidirectional protection configurations?
No, SA28ARL is a unidirectional TVS diode and must not be used for bidirectional transient suppression. Its internal Zener structure conducts only in reverse bias; forward conduction is limited to standard diode forward voltage (~3.5 V). For AC or bipolar signal line protection, a dedicated bidirectional device such as the CA28A variant-or a pair of unidirectional devices in series opposition-is required. The SA28ARL datasheet explicitly specifies "Unidirectional" in its title and electrical characterization tables.
What packaging options are available for SA28ARL?
SA28ARL is supplied in tape-and-reel format (5000 units per reel) with Pb-Free Surmetic axial lead construction (Case 59AA). The "RLG" suffix denotes this configuration, which includes RoHS-compliant plating, void-free transfer-molded plastic encapsulation, and cathode polarity band marking. Lead temperature rating is 260°C for 10 seconds at 1/16 inch from case-fully compatible with standard wave and selective soldering processes.
SA28ARL Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-204AC, DO-15, Axial
- Series:
- MiniMosorb™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 28V
- Voltage - Breakdown (Min):
- 31.1V
- Voltage - Clamping (Max) @ Ipp:
- 45.4V
- Current - Peak Pulse (10/1000µs):
- 11A
- Power - Peak Pulse:
- 500W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- Axial
SA28ARL FAQ
1.How can I place an order for SA28ARL through Aetrix?
Please submit a Request for Quotation (RFQ) for SA28ARL 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 SA28ARL reliable?
The price and inventory of SA28ARL are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SA28ARL is usually 5 days.
3.What payment methods are accepted for SA28ARL?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SA28ARL transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SA28ARL?
SA28ARL orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SA28ARL 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 SA28ARL?
For technical support, including SA28ARL datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SA28ARL requirements.
6.How does Aetrix verify that SA28ARL is sourced from the original manufacturer or authorized distributors?
All SA28ARL 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 SA28ARL meets industry standards.
7.What is the process for return or replacement of SA28ARL?
All SA28ARL units undergo pre-shipment inspection (PSI). If there is an issue with SA28ARL, 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 SA28ARL part is unused and in its original packaging.
Return procedure for SA28ARL:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SA28ARL Tags
-
ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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ESD5Z3.3T1G
onsemi
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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.
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DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
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D5V0L1B2WS-7
Diodes Incorporated
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