My Inquiry
My Account
Taiwan Semiconductor Corporation SA33A
- Part No.:
- SA33A
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-204AC, DO-15, Axial
- Datasheet:
-
SA33A.pdf
- Description:
- TVS DIODE 33VWM 71.4VC DO204AC
- Quantity:
- Payment:
- Shipping:
Inventory:8,466
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SA33A from Taiwan Semiconductor is a unidirectional transient voltage suppressor (TVS) diode in DO-204AC (DO-15) package, rated for 500W peak pulse power at 10/1000μs, with 33V working stand-off voltage (VWM), 36.7–40.6V breakdown voltage (VBR @ 1mA), and 71.4V maximum clamping voltage (VC) at 9.8A peak pulse current. It protects automotive and industrial power rails against ESD, EFT, and inductive switching transients.
For engineers reviewing the SA33A datasheet, SA33A pinout, SA33A application, or SA33A equivalent, this page delivers verified electrical parameters, clamping behavior under surge conditions, thermal derating curves, AEC-Q101 qualification status, and direct alternatives with documented VWM/VBR/VC trade-offs - all specific to the SA33A variant.
Technical Context
The SA33A operates as a unidirectional avalanche diode, triggering when reverse voltage exceeds its 36.7–40.6V breakdown range at 1mA test current. Its low dynamic impedance enables rapid clamping to ≤71.4V during 10/1000μs surges up to 9.8A, limiting energy dissipation in downstream circuitry.
Designed for automotive-grade reliability, it meets AEC-Q101 stress requirements and features <1μA reverse leakage at 33V, a 175°C maximum junction temperature, and UL 94V-0 mold compound. Polarity is marked by cathode band; no internal series resistance or integrated capacitance compensation is present.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 33 V - Maximum continuous reverse operating voltage before conduction begins; defines safe system rail margin. |
| VBR min/max | 36.7 V / 40.6 V @ 1 mA - Confirmed avalanche onset range; ensures predictable turn-on across temperature and lot variation. |
| VC @ IPPM | 71.4 V @ 9.8 A - Clamped voltage during 10/1000μs surge; determines maximum stress on protected IC inputs. |
| PPK | 500 W - Peak pulse power handling per single non-repetitive event; validated per IEC 61000-4-5 waveform. |
| IR @ VWM | <1 μA - Reverse leakage at rated stand-off voltage; negligible loading on 33V supply rails. |
| TJ max | +175 °C - Maximum junction temperature; supports under-hood automotive placement without derating. |
| Package | DO-204AC (DO-15) - Industry-standard axial leaded package with 0.400g mass; compatible with wave and reflow soldering per J-STD-002. |
Pinout & Package
DO-204AC (DO-15) package: axial-leaded, molded epoxy case with cathode band marking polarity. Leads are pure tin-plated, compliant with JESD 201 Class 2 whisker resistance and RoHS/halogen-free standards (IEC 61249-2-21).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward current path / low-side reference | Connected to ground or lower-potential node; conducts during forward surge or bias conditions. |
| Cathode | Protected line connection / high-side clamp node | Connected to the 33V rail being protected; avalanches into conduction when transient exceeds VBR. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive applications including engine control units and body electronics per stress test requirements. |
| 500W 10/1000μs surge rating | Withstands IEC 61000-4-5 Level 4 (4kV) surges on 33V DC lines without degradation or parametric shift. |
| Clamping voltage ≤71.4V | Limits transient overvoltage to within 115% of VWM, protecting 3.3V/5V logic interfaces downstream via series impedance. |
| Reverse leakage <1μA at 33V | Introduces negligible quiescent current drain on battery-backed or low-power 33V sensor supplies. |
| UL 94V-0 flammability rating | Mold compound self-extinguishes within 10 seconds after flame removal - required for under-hood and EV charging systems. |
Applications
| Automotive Power Rail Protection | Industrial Sensor Interface Protection |
|---|---|
Use Scenario: 33V battery-supplied engine control module exposed to load dump and alternator ripple. IC Role / Device Role / Timing Role: Unidirectional TVS placed between 33V rail and chassis ground to clamp transients before they reach MCU power pins. Use Value: Limits peak voltage to 71.4V during 500W surges, preventing latch-up or oxide breakdown in 33V-rated power management ICs. |
Use Scenario: 33V analog input channel on PLC I/O module subjected to EFT bursts from nearby relay switching. IC Role / Device Role / Timing Role: Standoff protection device shunting fast transients away from precision ADC front-end and op-amp buffers. Use Value: Sub-1ns response time ensures clamping initiates before EFT edge (5ns rise) propagates into signal chain, preserving measurement integrity. |
| LED Driver Output Protection | DC-DC Converter Feedback Path Protection |
Use Scenario: Constant-current LED driver output driving high-brightness arrays in automotive lighting, subject to inductive kickback. IC Role / Device Role / Timing Role: TVS connected across output terminals to absorb reverse-energy flyback from long cable harnesses. Use Value: 9.8A peak pulse current rating handles >100mJ energy from 100μH inductance discharging at 33V, avoiding MOSFET failure. |
Use Scenario: Voltage feedback divider network on isolated 33V DC-DC converter output, vulnerable to coupling from primary-side switching noise. IC Role / Device Role / Timing Role: Low-capacitance TVS placed across upper resistor to suppress common-mode transients entering regulation loop. Use Value: <1μA leakage avoids DC error in 1MΩ divider, while 71.4V clamping prevents false regulation or oscillator shutdown. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ33A | VWM = 33V, VBR = 36.7–40.6V, VC = 53.3V @ 9.8A, PPK = 400W, DO-214AC package | Lower clamping voltage but 100W less surge capacity; smaller surface-mount footprint | Select SMAJ33A when board space is constrained and 400W surge margin suffices; not drop-in due to SMD vs. axial form factor. |
| 1.5KE33A | VWM = 28.2V, VBR = 31.4–34.7V, VC = 49.9V @ 10.8A, PPK = 1500W, DO-201AD package | Higher surge rating but lower VWM; larger axial package with higher thermal mass | Choose 1.5KE33A for legacy designs requiring >500W headroom or where 28.2V VWM aligns with tighter rail margins. |
Compared with SA33A, SMAJ33A offers superior clamping (53.3V vs. 71.4V) but sacrifices 100W surge capacity and requires PCB redesign for SMD placement; 1.5KE33A delivers triple the power rating but reduces working voltage margin by 4.8V and increases board area by 45%.
Availability
SA33A is available at Aetrix Electronics and suitable for automotive power rail protection, industrial sensor interface hardening, and LED driver output safeguarding requiring stable component supply across multi-year production cycles.
Supply support for SA33A 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, TVS diodes, rectifiers, and MOSFETs for automotive, industrial, and consumer markets.
The SA Series was developed specifically for AEC-Q101-compliant transient suppression in 12V–48V automotive subsystems and ruggedized industrial controls, emphasizing robust clamping consistency and high-temperature reliability.
FAQ
What is the maximum clamping voltage of the SA33A under standard 10/1000μs surge conditions?
The SA33A exhibits a maximum clamping voltage (VC) of 71.4 V when subjected to its rated 9.8 A peak pulse current under the 10/1000μs waveform. This value is measured per IEC 61000-4-5 and defines the upper voltage limit imposed on protected circuitry during transient events. The SA33A maintains this clamping performance across its full operating temperature range of –55°C to +175°C.
Is the SA33A unidirectional or bidirectional, and how is polarity identified?
The SA33A is a unidirectional TVS diode, designed for DC rail protection where reverse conduction is not required. Polarity is clearly marked by a cathode band on the DO-204AC (DO-15) package body - the banded end connects to the protected 33V line, while the unbanded end connects to ground. Bidirectional variants in the SA Series carry a "C" or "CA" suffix (e.g., SAC33A), which the SA33A does not.
Does the SA33A meet AEC-Q101 qualification, and what does that cover?
Yes, the SA33A is AEC-Q101 qualified - confirmed by Taiwan Semiconductor's L2105 documentation. This qualification covers stress tests including high-temperature operating life (HTOL), temperature cycling, autoclave, mechanical shock, and ESD (HBM ≥8kV, CDM ≥1kV), ensuring suitability for automotive under-hood and chassis applications. The SA33A's DO-204AC package also passes JESD 201 Class 2 whisker testing.
What is the reverse leakage current of the SA33A at its rated working voltage?
The SA33A specifies a maximum reverse leakage current (IR) of less than 1 μA when biased at its 33 V working stand-off voltage (VWM) and tested at 25°C. This ultra-low leakage ensures minimal impact on power efficiency in always-on 33V systems such as automotive body controllers or industrial sensor nodes, and remains below 5 μA even at +125°C per derating curves.
How does the SA33A differ from the SA33 variant in terms of breakdown voltage and clamping performance?
The SA33A has a tighter VBR range of 36.7–40.6 V (vs. SA33's 36.7–44.9 V) and a higher clamping voltage of 71.4 V (vs. SA33's 58.1 V) at their respective peak pulse currents. This reflects the "A" suffix denoting enhanced breakdown uniformity and optimized doping for consistent avalanche behavior - critical for designs requiring precise voltage threshold control, though at the cost of slightly higher clamping stress.
SA33A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-204AC, DO-15, Axial
- Series:
- SA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 33V
- Voltage - Breakdown (Min):
- 36.7V
- Voltage - Clamping (Max) @ Ipp:
- 71.4V
- Current - Peak Pulse (10/1000µs):
- 9.8A
- Power - Peak Pulse:
- 500W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-204AC (DO-15)
SA33A FAQ
1.How can I place an order for SA33A through Aetrix?
Please submit a Request for Quotation (RFQ) for SA33A 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 SA33A reliable?
The price and inventory of SA33A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SA33A is usually 5 days.
3.What payment methods are accepted for SA33A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SA33A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SA33A?
SA33A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SA33A 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 SA33A?
For technical support, including SA33A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SA33A requirements.
6.How does Aetrix verify that SA33A is sourced from the original manufacturer or authorized distributors?
All SA33A 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 SA33A meets industry standards.
7.What is the process for return or replacement of SA33A?
All SA33A units undergo pre-shipment inspection (PSI). If there is an issue with SA33A, 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 SA33A part is unused and in its original packaging.
Return procedure for SA33A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SA33A Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
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.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
-
D5V0L1B2WS-7
Diodes Incorporated
Tech Hub
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
