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onsemi SA33CA
- Part No.:
- SA33CA
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-204AC, DO-15, Axial
- Datasheet:
-
SA33CA.pdf
- Description:
- TVS DIODE 33VWM 53.3VC DO15
- Quantity:
- Payment:
- Shipping:
Inventory:6,396
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Product details
Overview
SA33CA from Fairchild Semiconductor is a bidirectional 500 W transient voltage suppressor (TVS) diode in DO-15 package, designed for clamping ESD and surge transients in power and signal lines. It features a 33 V reverse stand-off voltage (VRWM), 36.7–40.6 V breakdown voltage (VBR), 53.3 V clamping voltage at peak pulse current, and operates up to +175 °C junction temperature.
For engineers reviewing the SA33CA datasheet, pinout, applications, or equivalent options, this device is selected for robust overvoltage protection in DC power rails, industrial I/O interfaces, and automotive body electronics where fast response (<5 ns), low leakage (<1 µA at VRWM), and high peak pulse current (9.4 A on 10/1000 µs waveform) are critical.
Technical Context
The SA33CA is a glass-passivated, bidirectional TVS diode optimized for unidirectional and bidirectional transient suppression without polarity sensitivity. Its clamping behavior is defined by a low incremental surge resistance and stable VBR tolerance (±5% typical), enabling predictable protection across temperature and aging.
It delivers 500 W peak pulse power on the standardized 10/1000 µs waveform per JEDEC standards, with thermal derating above 75 °C ambient and a maximum junction temperature of +175 °C - supporting operation in harsh industrial and automotive under-hood environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power (10/1000 µs) | 500 W - sustains single high-energy surges per IEC 61000-4-5 Level 4 without failure |
| Reverse Stand-off Voltage (VRWM) | 33 V - maximum continuous DC or RMS voltage before significant leakage begins |
| Breakdown Voltage (VBR) | 36.7–40.6 V at 1.0 mA - defines onset of avalanche conduction during overvoltage events |
| Clamping Voltage (VC) | 53.3 V at 9.4 A IPPM - limits protected circuit voltage during full-rated surge |
| Peak Pulse Current (IPPM) | 9.4 A on 10/1000 µs waveform - quantifies maximum transient current it can safely divert |
| Reverse Leakage (IR) | <1 µA at 33 V - ensures minimal power loss and signal integrity in standby |
| Response Time | <5 ns - enables effective suppression of fast-rising ESD and lightning-induced transients |
Pinout & Package
SA33CA is housed in a DO-15 axial-leaded package with no cathode band (bidirectional configuration). Leads are tinned and rated for 0.375" lead length at 75 °C ambient.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode / Cathode (symmetrical) | Transient current path | Identical terminals - bidirectional conduction allows placement without polarity concern |
Key Features
| Feature | Design Value |
|---|---|
| Glass-passivated junction | Enhances long-term reliability and moisture resistance in humid or contaminated environments |
| 500 W peak pulse rating | Meets IEC 61000-4-5 surge immunity requirements for industrial and automotive applications |
| Fast response time (<5 ns) | Protects sensitive downstream ICs before transient energy reaches them |
| Low incremental surge resistance | Minimizes clamping voltage overshoot during high-current transients |
| Stable VBR tolerance (±5%) | Ensures consistent protection threshold across production lots and temperature range |
Applications
| Industrial PLC I/O Protection | Automotive Body Control Module |
|---|---|
Use Scenario: Protecting 24 V DC sensor inputs and relay driver outputs against load dump and inductive switching transients. IC Role / Device Role / Timing Role: Primary overvoltage clamp placed at connector entry point before signal conditioning circuitry. Use Value: Limits transient voltage to ≤53.3 V, preventing damage to microcontrollers and analog front-ends while maintaining <1 µA leakage at nominal 24 V rail. |
Use Scenario: Safeguarding LIN bus transceivers and LED driver circuits from battery line transients during jump-start or alternator load dump. IC Role / Device Role / Timing Role: Bidirectional clamping element on 12 V supply rail and LIN signal line. Use Value: Responds in <5 ns to suppress 100 V/100 ms load dump spikes, with no polarity constraints simplifying PCB layout. |
| DC Power Supply Input Stage | Telecom Equipment Surge Port |
Use Scenario: Front-end protection for 36 V input DC-DC converters in railway or solar charge controllers. IC Role / Device Role / Timing Role: First-line transient suppressor between input connector and bulk capacitor. Use Value: Clamps 500 W surges to 53.3 V, allowing downstream TVS or MOV staging while operating reliably up to +175 °C junction temperature. |
Use Scenario: Secondary-level surge protection on low-voltage telecom interface ports (e.g., RS-485, Ethernet PoE injectors). IC Role / Device Role / Timing Role: Fast-acting clamp after primary GDT or MOV, handling residual fast transients. Use Value: Low capacitance and sub-5 ns response preserve signal integrity on data lines while limiting voltage excursions to safe levels for PHY ICs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ33CA | DO-214AA package, 600 W rating, 53.3 V VC, same VRWM/VBR range | Higher power density and surface-mount compatibility; requires rework of through-hole footprint | Select when board space is constrained and SMT assembly is preferred |
| P6SMB33CA | DO-214AA package, 600 W rating, 53.3 V VC, identical electrical specs but tighter VBR tolerance (±3.5%) | Same mounting style as SMBJ33CA; slightly improved consistency in clamping threshold | Choose for higher-volume production where tighter parametric control improves test yield |
Compared with SA33CA, SMBJ33CA and P6SMB33CA offer higher peak power and SMT compatibility but require PCB redesign; SA33CA remains optimal for cost-sensitive, through-hole industrial designs requiring proven field reliability and thermal margin at elevated ambient temperatures.
Availability
SA33CA is available at Aetrix Electronics and suitable for industrial PLC I/O protection, automotive body control modules, and DC power supply input stages requiring stable component supply and long-lifecycle support.
Supply support for SA33CA 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
Fairchild Semiconductor (now part of ON Semiconductor) is a global leader in power management and protection semiconductors, known for high-reliability discrete devices and analog ICs.
The SAxxCA series was developed specifically for ruggedized transient suppression in industrial automation and automotive subsystems, emphasizing thermal robustness, bidirectional symmetry, and JEDEC-compliant surge handling.
FAQ
What is the maximum operating junction temperature for SA33CA?
The SA33CA has a maximum operating junction temperature of +175 °C, verified per Absolute Maximum Ratings in the Fairchild datasheet Rev. D. This rating enables reliable use in high-temperature environments such as engine compartments or enclosed industrial enclosures. Derating curves confirm sustained operation at full 500 W pulse power up to 75 °C ambient, with linear reduction above that point. The SA33CA's glass-passivated junction contributes to this thermal resilience.
Is SA33CA unidirectional or bidirectional, and how does that affect circuit placement?
SA33CA is a bidirectional TVS diode, indicated by the "CA" suffix and confirmed by its symmetric electrical characteristics in both polarities. Unlike unidirectional variants (e.g., SA33A), it has no cathode band and may be installed without orientation concern. This simplifies PCB layout and eliminates risk of reverse installation in AC-coupled or floating signal paths - a key advantage in LIN bus or RS-485 protection where polarity is undefined.
What is the clamping voltage of SA33CA at its rated peak pulse current?
The SA33CA clamps to 53.3 V at its rated peak pulse current of 9.4 A on the standard 10/1000 µs waveform. This value is measured per JEDEC test conditions and represents the maximum voltage seen by downstream circuitry during a full-rated surge event. It is derived directly from the Electrical Characteristics table in the SA5V0(C)A–SA170(C)A datasheet Rev. D and is critical for ensuring protected ICs remain within their absolute maximum voltage ratings.
Does SA33CA meet IEC 61000-4-5 surge immunity requirements?
Yes, the SA33CA's 500 W peak pulse power rating on the 10/1000 µs waveform aligns with IEC 61000-4-5 Level 4 (4 kV line-to-earth, 2 kV line-to-line) for industrial environments. Its fast <5 ns response and low clamping voltage ensure effective energy diversion before system-level damage occurs. System-level compliance depends on proper PCB layout and coordination with upstream filters, but the SA33CA is a validated first-stage protector in certified designs.
What is the reverse leakage current specification for SA33CA at its VRWM?
The SA33CA exhibits reverse leakage current (IR) of less than 1 µA at its 33 V reverse stand-off voltage (VRWM), as specified in the Electrical Characteristics table. This low leakage preserves efficiency in always-on power rails and avoids false triggering in high-impedance sensing circuits. The value is guaranteed at TA = 25 °C and remains below 10 µA even at +85 °C ambient, supporting stable performance across industrial temperature ranges.
SA33CA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-204AC, DO-15, Axial
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 33V
- Voltage - Breakdown (Min):
- 36.7V
- Voltage - Clamping (Max) @ Ipp:
- 53.3V
- Current - Peak Pulse (10/1000µs):
- 9.4A
- Power - Peak Pulse:
- 500W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-15
SA33CA FAQ
1.How can I place an order for SA33CA through Aetrix?
Please submit a Request for Quotation (RFQ) for SA33CA 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 SA33CA reliable?
The price and inventory of SA33CA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SA33CA is usually 5 days.
3.What payment methods are accepted for SA33CA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SA33CA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SA33CA?
SA33CA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SA33CA 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 SA33CA?
For technical support, including SA33CA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SA33CA requirements.
6.How does Aetrix verify that SA33CA is sourced from the original manufacturer or authorized distributors?
All SA33CA 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 SA33CA meets industry standards.
7.What is the process for return or replacement of SA33CA?
All SA33CA units undergo pre-shipment inspection (PSI). If there is an issue with SA33CA, 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 SA33CA part is unused and in its original packaging.
Return procedure for SA33CA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SA33CA Tags
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ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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onsemi
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Diodes Incorporated
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Diodes Incorporated
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DESD5V0U1BA-7
Diodes Incorporated
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ESD5Z5.0T1G
onsemi
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DESD5V0U1BB-7
Diodes Incorporated
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Diodes Incorporated
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PESD2V0Y1BSFYL
Nexperia USA Inc.
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Toshiba Semiconductor and Storage
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Diodes Incorporated
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