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Home > Products > Circuit Protection > Transient Voltage Suppressors (TVS) > TVS Diodes

Taiwan Semiconductor Corporation P4SMA43

Name: P4SMA43
Brand: Taiwan Semiconductor Corporation
SKU: P4SMA43
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: P4SMA43

Manufacturer:: Taiwan Semiconductor Corporation

Category:: TVS Diodes

Package:: DO-214AC, SMA

Datasheet:: P4SMA43.pdf

Description:: 400W, 43V, 10%, UNIDIRECTIONAL,

Quantity:: RFQ Add To RFQ list

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Product details

Overview

P4SMA43 from Taiwan Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode designed for overvoltage protection in DC power lines and signal paths. It features a 34.8 V working stand-off voltage, 38.7–47.3 V breakdown voltage at 1 mA, 61.9 V maximum clamping voltage under 6.7 A 10/1000 µs surge, and 400 W peak pulse power rating in DO-214AC (SMA) package - deployed in SMPS input stages and DC/DC converter rails.

For engineers reviewing the P4SMA43 datasheet, P4SMA43 pinout, P4SMA43 application, or P4SMA43 equivalent, key selection criteria include clamping performance at rated surge current, junction temperature derating above 25°C, unidirectional polarity marking, and compliance with ISO 7637-2 Pulse 1/2a/2b/3a/3b for automotive electronics robustness.

Technical Context

The P4SMA43 operates as a silicon avalanche diode with glass-passivated junction, optimized for fast response (<1.0 ps) to transient events. Its unidirectional configuration provides reverse-biased clamping only, with cathode band marking indicating polarity - critical for correct PCB orientation in series-connected protection circuits.

It delivers 400 W peak pulse power (10/1000 µs waveform) at 25°C, derated linearly above that ambient per Fig.2, and supports operating junction temperatures from –55°C to +150°C. The device exhibits <1 µA reverse leakage at 34.8 V and a V_BR temperature coefficient of 0.101 %/°C.

Key Specifications

Parameter	Value and Actual Design Meaning
V_WM	34.8 V - Maximum continuous reverse voltage before significant leakage; sets upper limit for normal circuit operation.
V_BR min/max	38.7 V / 47.3 V at 1 mA - Confirmed avalanche onset range; ensures reliable triggering across process variation.
V_C@I_PPM	61.9 V at 6.7 A (10/1000 µs) - Clamped voltage during worst-case surge; defines protected circuit's maximum stress level.
P_PPM	400 W - Peak transient energy absorption capability; enables protection against ISO 7637-2 Pulse 1/2a/2b/3a/3b transients.
I_R@V_WM	<1 µA - Ultra-low leakage ensures minimal standby power loss and no interference with high-impedance sensing nodes.
T_J max	+150°C - Enables use in thermally constrained environments such as enclosed power adapters or under-hood automotive modules.

Pinout & Package

Package: DO-214AC (SMA), surface-mount, single-diode unidirectional configuration with molded epoxy case meeting UL 94V-0, matte tin-plated leads, and cathode band marking.

Pin/Terminal	Circuit Role	Design Meaning
Anode	Forward conduction terminal	Connected to lower-potential side (e.g., GND or return path); conducts during forward surge or ESD event.
Cathode	Reverse-biased clamping terminal	Connected to protected line (e.g., +12 V rail); avalanches into low-impedance state when V_AK exceeds V_BR.

Key Features

Feature	Design Value
Glass passivated junction	Ensures stable V_BR and low leakage over lifetime; resists humidity-induced degradation in industrial environments.
Fast response time <1.0 ps	Clamps transients before sensitive downstream ICs experience overstress - critical for protecting USB, CAN, or MCU I/O pins.
ISO 7637-2 compliance	Validated for automotive load-dump and supply-line transient immunity (Pulse 1/2a/2b/3a/3b), enabling drop-in use in vehicle ECUs.
Moisture sensitivity level 1	Eliminates bake requirements prior to reflow; compatible with standard SMT assembly without special handling.

Applications

Switching Mode Power Supply (SMPS)	On-board DC/DC Converter
Use Scenario: Protection of primary-side rectifier output or secondary-side 12 V/5 V distribution bus against switching noise and load dump. IC Role / Device Role / Timing Role: Unidirectional TVS diode placed in parallel with bulk capacitor to clamp voltage spikes exceeding 34.8 V. Use Value: Limits peak rail voltage to ≤61.9 V during 6.7 A surges, preventing MOSFET gate oxide rupture and controller latch-up.	Use Scenario: Input rail protection for point-of-load (POL) converters in telecom base stations or server motherboards. IC Role / Device Role / Timing Role: Standoff-rated clamping device on 48 V or 24 V input, absorbing coupled transients from adjacent digital switching sections. Use Value: Maintains system uptime by suppressing >400 W transients without degradation - verified per JESD22-A114E ESD testing.
Lighting Application	Adapters
Use Scenario: Overvoltage suppression on LED driver input in outdoor streetlight systems exposed to lightning-induced surges. IC Role / Device Role / Timing Role: Primary-line TVS connected between AC-DC rectified output and bulk cap, triggered within picoseconds. Use Value: Withstands repeated 10/1000 µs surges up to 400 W while maintaining <1 µA leakage - preserving driver efficiency and thermal margin.	Use Scenario: Input-stage protection in universal-input wall adapters (90–264 VAC) against mains-borne transients and hot-plug events. IC Role / Device Role / Timing Role: Unidirectional suppressor on DC output rail (e.g., 12 V/19 V), oriented to clamp negative-going spikes. Use Value: Enables compact SMA footprint without sacrificing clamping performance - meets IEC/EN 61000-4-5 Level 3 requirements.

Switching Mode Power Supply (SMPS)

On-board DC/DC Converter

Use Scenario: Protection of primary-side rectifier output or secondary-side 12 V/5 V distribution bus against switching noise and load dump.

IC Role / Device Role / Timing Role: Unidirectional TVS diode placed in parallel with bulk capacitor to clamp voltage spikes exceeding 34.8 V.

Use Value: Limits peak rail voltage to ≤61.9 V during 6.7 A surges, preventing MOSFET gate oxide rupture and controller latch-up.

Use Scenario: Input rail protection for point-of-load (POL) converters in telecom base stations or server motherboards.

IC Role / Device Role / Timing Role: Standoff-rated clamping device on 48 V or 24 V input, absorbing coupled transients from adjacent digital switching sections.

Use Value: Maintains system uptime by suppressing >400 W transients without degradation - verified per JESD22-A114E ESD testing.

Lighting Application

Adapters

Use Scenario: Overvoltage suppression on LED driver input in outdoor streetlight systems exposed to lightning-induced surges.

IC Role / Device Role / Timing Role: Primary-line TVS connected between AC-DC rectified output and bulk cap, triggered within picoseconds.

Use Value: Withstands repeated 10/1000 µs surges up to 400 W while maintaining <1 µA leakage - preserving driver efficiency and thermal margin.

Use Scenario: Input-stage protection in universal-input wall adapters (90–264 VAC) against mains-borne transients and hot-plug events.

IC Role / Device Role / Timing Role: Unidirectional suppressor on DC output rail (e.g., 12 V/19 V), oriented to clamp negative-going spikes.

Use Value: Enables compact SMA footprint without sacrificing clamping performance - meets IEC/EN 61000-4-5 Level 3 requirements.

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient voltage suppression applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
SMBJ43A	DO-214AA (SMB) package; 43 V nominal V_BR; 64.5 V V_C @ 6.2 A; same 400 W rating.	Larger footprint (SMB vs SMA); higher thermal mass but requires more PCB area.	Select SMBJ43A when board space allows and higher thermal inertia is preferred for repetitive surge duty cycles.
1.5SMC43A	DO-214AB (SMC) package; 43 V nominal V_BR; 69.4 V V_C @ 5.8 A; 1500 W rating (10/1000 µs).	Higher power rating but larger size; less precise clamping due to higher V_C.	Choose 1.5SMC43A only if system-level surge tests exceed 400 W and layout permits SMC footprint.

Compared with SMBJ43A and 1.5SMC43A, the P4SMA43 offers identical clamping voltage precision and tighter V_BR tolerance in the smallest DO-214 surface-mount package, making it optimal for space-constrained DC/DC inputs and adapter secondary-side rails where thermal cycling reliability is critical.

Availability

P4SMA43 is available at Aetrix Electronics and suitable for switching mode power supplies, lighting drivers, and on-board DC/DC converters requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for P4SMA43 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 analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, specializing in TVS diodes, rectifiers, and power MOSFETs since 1979.

The P4SMA43 belongs to TSC's P4SMAxx family of 400 W surface-mount TVS diodes engineered specifically for cost-sensitive, high-volume industrial and automotive power rail protection with stringent ISO 7637-2 compliance.

FAQ

What is the maximum clamping voltage of the P4SMA43 under standard test conditions?

The P4SMA43 has a maximum clamping voltage (V_C) of 61.9 V when subjected to a 10/1000 µs surge current pulse of 6.7 A at 25°C ambient. This value is measured across the device terminals during peak impulse and defines the highest voltage seen by downstream circuitry during transient events - a critical parameter for ensuring safe operation of connected ICs and passives.

Is the P4SMA43 suitable for bidirectional transient protection?

No, the P4SMA43 is a unidirectional TVS diode and is not rated for bidirectional operation. Its electrical specifications apply only in the reverse direction; forward conduction is limited to 3.5 V at 25 A. For bidirectional protection, select the P4SMA43A variant or a CA-suffixed part - both explicitly specified for symmetrical clamping in either polarity.

What does the marking code 'BYJ' indicate on the P4SMA43 device body?

The marking code 'BYJ' on the P4SMA43 identifies the specific voltage grade and manufacturing lot per Taiwan Semiconductor's internal coding scheme. It corresponds exclusively to the 38.7–47.3 V breakdown range and confirms the device meets all published electrical and mechanical specifications for the P4SMA43, including V_WM = 34.8 V and V_C = 61.9 V.

How does the P4SMA43 perform at elevated ambient temperatures?

The P4SMA43's peak pulse power rating is derated linearly above 25°C per Figure 2 in the datasheet, reaching ~200 W at +85°C and ~100 W at +125°C. Its maximum junction temperature remains +150°C, allowing continued operation in thermally demanding environments such as enclosed power adapters - provided PCB copper area and airflow meet thermal design guidelines.

Does the P4SMA43 comply with RoHS and halogen-free standards?

Yes, the P4SMA43 is RoHS compliant and halogen-free per IEC 61249-2-21. Its molding compound meets UL 94V-0 flammability rating, and its matte tin-plated leads satisfy J-STD-002 solderability requirements - confirming suitability for lead-free reflow processes and environmentally regulated end markets including EU automotive and industrial equipment.

P4SMA43 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:: 1

Bidirectional Channels:: -

Voltage - Reverse Standoff (Typ):: 34.8V

Voltage - Breakdown (Min):: 38.7V

Voltage - Clamping (Max) @ Ipp:: 61.9V

Current - Peak Pulse (10/1000µs):: 6.7A

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)

P4SMA43 FAQ

1.How can I place an order for P4SMA43 through Aetrix?

Please submit a Request for Quotation (RFQ) for P4SMA43 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 P4SMA43 reliable?

The price and inventory of P4SMA43 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for P4SMA43 is usually 5 days.

3.What payment methods are accepted for P4SMA43?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for P4SMA43 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for P4SMA43?

P4SMA43 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your P4SMA43 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 P4SMA43?

For technical support, including P4SMA43 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your P4SMA43 requirements.

6.How does Aetrix verify that P4SMA43 is sourced from the original manufacturer or authorized distributors?

All P4SMA43 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 P4SMA43 meets industry standards.

7.What is the process for return or replacement of P4SMA43?

All P4SMA43 units undergo pre-shipment inspection (PSI). If there is an issue with P4SMA43, 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 P4SMA43 part is unused and in its original packaging.

Return procedure for P4SMA43:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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