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Taiwan Semiconductor Corporation P4SMA18CA
- Part No.:
- P4SMA18CA
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
P4SMA18CA.pdf
- Description:
- TVS DIODE 15.3VWM 25.5VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:6,975
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Product details
Overview
P4SMA18CA from Taiwan Semiconductor is a bidirectional surface-mount Transient Voltage Suppressor (TVS) diode designed for robust overvoltage protection in DC power rails and signal lines. It features a 15.3 V working stand-off voltage (VWM), 17.1–18.9 V breakdown voltage (VBR) at 1 mA, 25.5 V maximum clamping voltage (VC) at 16.5 A peak pulse current, and 400 W peak pulse power rating under 10/1000 µs waveform - deployed in switching mode power supplies and on-board DC/DC converters.
For engineers reviewing the P4SMA18CA datasheet, P4SMA18CA pinout, P4SMA18CA application, or P4SMA18CA equivalent, key selection criteria include bidirectional clamping capability, DO-214AC (SMA) package compatibility, low leakage (<1 µA at VWM), ISO 7637-2 Pulse 1/2a/2b/3a/3b compliance, and junction temperature range of –55°C to +150°C.
Technical Context
The P4SMA18CA implements a glass-passivated silicon avalanche junction optimized for fast transient suppression with sub-1 ps response time. Its bidirectional configuration enables symmetric clamping in both polarities without external polarity management, supporting unidirectional or bidirectional signal/power line protection.
It operates within a –55°C to +150°C junction temperature range and is rated for 400 W non-repetitive peak pulse power (10/1000 µs), with thermal derating above 25°C ambient per published curve. The device meets JESD201 Class 2 whisker resistance and UL 94V-0 flammability requirements for the molding compound.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 15.3 V - Maximum continuous reverse operating voltage before significant leakage begins; defines safe DC bias margin. |
| VBR (min/max) | 17.1 V / 18.9 V at 1 mA - Confirmed breakdown threshold range; ensures predictable turn-on during transients. |
| VC @ IPPM | 25.5 V at 16.5 A (10/1000 µs) - Clamped voltage seen by protected circuit during worst-case surge; limits downstream stress. |
| PPPM | 400 W - Peak pulse power handling capacity; supports automotive load-dump and ISO 7637-2 compliant surges. |
| IR @ VWM | <1 µA - Ultra-low reverse leakage at rated stand-off voltage; minimizes standby power loss in battery-powered systems. |
| TJ Range | –55°C to +150°C - Full industrial temperature operation; enables use in under-hood automotive and high-ambient industrial environments. |
| Package | DO-214AC (SMA) - Standard surface-mount outline with matte tin-plated leads; compatible with automated reflow assembly. |
Pinout & Package
DO-214AC (SMA) package: molded plastic case with axial-leaded configuration; cathode band denotes polarity for unidirectional variants - but P4SMA18CA is bidirectional, so marking band indicates terminal symmetry rather than polarity; terminals are electrically identical and interchangeable.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode/Cathode (symmetrical) | Bidirectional avalanche junction terminals | Either terminal may serve as input or return path; no polarity dependency in layout or routing. |
| Case | Non-conductive molded body | No thermal or electrical connection to PCB pad; thermal path relies solely on soldered leads. |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional clamping | Enables single-device protection of AC-coupled or floating DC lines without external diode pairing. |
| Glass-passivated junction | Ensures stable VBR over lifetime and improved reliability vs. epoxy-passivated alternatives in humid or thermally cycled environments. |
| ISO 7637-2 compliance | Validated against Pulse 1 (inductive load dump), Pulse 2a/2b (switching transients), and Pulse 3a/3b (capacitive coupling), critical for automotive ECUs. |
| Moisture sensitivity level 1 | Zero bake requirement prior to reflow; simplifies SMT line integration and eliminates moisture-related popcorning risk. |
| Halogen-free & RoHS | Meets IEC 61249-2-21 and EU RoHS Directive; supports environmentally compliant end-product certifications. |
Applications
| Switching Mode Power Supply (SMPS) | Automotive Body Control Module (BCM) |
|---|---|
Use Scenario: Protection of 12 V input rail against load dump and alternator ripple in offline AC/DC adapters. IC Role / Device Role / Timing Role: Primary overvoltage clamp placed across input capacitor to limit transient excursions to ≤25.5 V. Use Value: Prevents damage to upstream rectifier and downstream PWM controller ICs during ISO 7637-2 Pulse 5a events up to 400 W. |
Use Scenario: Input protection for LIN bus transceivers and microcontroller I/O pins exposed to vehicle battery transients. IC Role / Device Role / Timing Role: Bidirectional shunt element absorbing negative-going spikes (Pulse 3b) and positive surges (Pulse 2a) on shared power/signal nets. Use Value: Eliminates need for separate uni-directional TVS pairs while maintaining <1 µA leakage at 15.3 V nominal rail. |
| LED Driver for Automotive Lighting | Industrial On-Board DC/DC Converter |
Use Scenario: Surge suppression on constant-current LED string supply lines subject to hot-swap and cable discharge events. IC Role / Device Role / Timing Role: Fast-response clamp limiting voltage overshoot during 10/1000 µs ESD-like transients on 24 V supply inputs. Use Value: Maintains LED driver IC functionality by holding clamped voltage below 25.5 V - well under typical 36 V absolute max ratings. |
Use Scenario: Input-side protection of isolated 48 V-to-12 V DC/DC modules in factory automation controllers. IC Role / Device Role / Timing Role: Standoff-rated TVS absorbing repetitive switching noise and accidental 120 VAC cross-connect surges. Use Value: Enables reliable operation across –40°C to +85°C ambient with no derating required up to 75°C board temperature. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ18CA (Bourns) | Same DO-214AA package; 400 W rating; VWM = 15.4 V, VC = 28.8 V at 13.9 A - higher clamping voltage than P4SMA18CA's 25.5 V. | Higher VC reduces margin for downstream 24 V-rated ICs; suitable where layout space allows larger SMB footprint. | Select when DO-214AA board footprint is fixed and higher surge current tolerance (13.9 A vs. 16.5 A) is secondary to package standardization. |
| 1.5KE18CA (ON Semiconductor) | Through-hole DO-15 package; same 15.3 V VWM and 25.5 V VC, but 1500 W rating and 120 A IPPM - significantly higher energy handling. | Not surface-mountable; requires manual or wave-solder process; unsuitable for high-density automated PCBs. | Choose only for legacy through-hole designs or where >1 kV/µs surge immunity and 1500 W dissipation outweigh SMT assembly constraints. |
Compared with SMBJ18CA and 1.5KE18CA, the P4SMA18CA delivers optimal balance of low clamping voltage (25.5 V), DO-214AC SMT compatibility, and 400 W surge capability - making it preferred for space-constrained, high-reliability automotive and industrial DC/DC front-end protection where precise voltage limiting is critical.
Availability
P4SMA18CA is available at Aetrix Electronics and suitable for switching mode power supplies, automotive body control modules, and industrial on-board DC/DC converters requiring stable component supply, full traceability, and long-term lifecycle support.
Supply support for P4SMA18CA 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
Taiwan Semiconductor Corporation (TSC) is a vertically integrated semiconductor manufacturer specializing in discrete power devices, including TVS diodes, rectifiers, and MOSFETs, with global distribution and AEC-Q200 qualified product lines.
The P4SMA18CA belongs to TSC's P4SMAx CA series of bidirectional surface-mount TVS diodes engineered specifically for ISO 7637-2-compliant automotive and industrial transient suppression in compact, high-volume SMT applications.
FAQ
What is the clamping voltage of P4SMA18CA and how is it measured?
The P4SMA18CA has a maximum clamping voltage (VC) of 25.5 V, measured at 16.5 A peak pulse current under the standardized 10/1000 µs double-exponential waveform. This value represents the highest voltage the device allows across its terminals during a transient event, ensuring downstream components remain within safe operating limits. The test condition is defined in the datasheet and aligns with IEC 61000-4-5 and ISO 7637-2 standards.
Is P4SMA18CA unidirectional or bidirectional, and how does that affect circuit design?
P4SMA18CA is a bidirectional TVS diode, indicated by the "CA" suffix. It provides symmetrical clamping in both polarities, eliminating the need for polarity-aware placement or additional components. In circuit design, this allows direct placement across any two-node interface - such as power/ground, differential signal lines, or floating DC rails - without regard to orientation, simplifying layout and improving robustness against reverse-polarity transients.
Does P4SMA18CA meet automotive transient immunity standards?
Yes, P4SMA18CA meets ISO 7637-2 requirements for Pulse 1 (inductive load dump), Pulse 2a/2b (switching transients), and Pulse 3a/3b (capacitive coupling), as explicitly stated in the manufacturer's documentation. Its 400 W peak pulse power rating and 25.5 V clamping voltage are validated under these waveforms, making it suitable for front-end protection in automotive ECUs, lighting modules, and body control units.
What is the maximum operating temperature for P4SMA18CA, and how does thermal derating work?
The P4SMA18CA has a maximum junction temperature (TJ) of +150°C and operates from –55°C to +150°C. Its peak pulse power rating of 400 W is specified at TA = 25°C and must be linearly derated above that ambient temperature, following the published pulse derating curve (Figure 2 in the datasheet). At 100°C ambient, for example, the usable peak power drops to approximately 240 W - a critical consideration for under-hood or enclosed industrial applications.
Can P4SMA18CA be used in place of a unidirectional TVS like P4SMA18A?
No - P4SMA18CA and P4SMA18A serve fundamentally different functions. P4SMA18A is unidirectional and intended for DC-biased lines with defined polarity; P4SMA18CA is bidirectional and suited for AC-coupled, floating, or polarity-agnostic paths. Substituting one for the other without verifying circuit topology risks ineffective clamping or forward conduction during normal operation. Always match the "A" (unidirectional) or "CA" (bidirectional) suffix to system-level signal behavior.
P4SMA18CA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-214AC, SMA
- Series:
- P4SMA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 15.3V
- Voltage - Breakdown (Min):
- 17.1V
- Voltage - Clamping (Max) @ Ipp:
- 25.5V
- Current - Peak Pulse (10/1000µs):
- 16.5A
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC (SMA)
P4SMA18CA FAQ
1.How can I place an order for P4SMA18CA through Aetrix?
Please submit a Request for Quotation (RFQ) for P4SMA18CA 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 P4SMA18CA reliable?
The price and inventory of P4SMA18CA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for P4SMA18CA is usually 5 days.
3.What payment methods are accepted for P4SMA18CA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for P4SMA18CA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for P4SMA18CA?
P4SMA18CA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your P4SMA18CA 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 P4SMA18CA?
For technical support, including P4SMA18CA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your P4SMA18CA requirements.
6.How does Aetrix verify that P4SMA18CA is sourced from the original manufacturer or authorized distributors?
All P4SMA18CA 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 P4SMA18CA meets industry standards.
7.What is the process for return or replacement of P4SMA18CA?
All P4SMA18CA units undergo pre-shipment inspection (PSI). If there is an issue with P4SMA18CA, 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 P4SMA18CA part is unused and in its original packaging.
Return procedure for P4SMA18CA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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