My Inquiry
My Account
onsemi SZ1SMB24CAT3G
- Part No.:
- SZ1SMB24CAT3G
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SZ1SMB24CAT3G.pdf
- Description:
- TRANS VOLTAGE SUPPRESSOR DIODE,
- Quantity:
- Payment:
- Shipping:
Inventory:354,500
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SZ1SMB24CAT3G from onsemi is a bidirectional 600 W peak power Zener transient voltage suppressor (TVS) designed for parallel overvoltage protection of sensitive electronics. It features a 24 V working peak reverse voltage (VRWM), 29.5 V maximum clamping voltage at 15.4 A peak pulse current, and <1 ns response time-ideal for safeguarding automotive power rails and industrial I/O interfaces against ESD and lightning-induced surges.
For engineers reviewing the SZ1SMB24CAT3G datasheet, pinout, applications, or equivalent options, key selection criteria include clamping performance under 10/1000 µs surge, UL 497B certification for isolated loop protection, AEC-Q101 qualification, and SMB package thermal robustness in high-temperature ambient environments.
Technical Context
This device operates as a voltage-clamped shunt protector: when transient voltage exceeds its breakdown threshold (28.11 V min @ 1 mA), it rapidly avalanches to divert surge current away from downstream circuitry. Its low zener impedance and fast turn-on (<1 ns) minimize overshoot during fast-rising transients such as ESD or inductive switching spikes.
The SZ1SMB24CAT3G is rated for 600 W peak power at 1 ms pulse width, with derating above 25 °C ambient per Figure 3. It exhibits 366 pF typical junction capacitance at 0 V bias (1 MHz), making it suitable for DC and low-frequency signal lines-not high-speed data buses.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 24 V - Maximum continuous reverse operating voltage before clamping begins; must exceed system's normal DC or peak AC rail voltage. |
| VBR (min) | 28.11 V @ 1 mA - Guaranteed avalanche initiation voltage; ensures reliable triggering above nominal operating range. |
| VC @ IPP | 38.9 V @ 15.4 A - Clamped voltage during 10/1000 µs surge; defines worst-case stress on protected load. |
| PPK | 600 W @ 1 ms - Peak surge energy handling capacity; validates suitability for IEC 61000-4-5 Level 3/4 tests. |
| IR @ VRWM | <5 µA - Negligible leakage at rated working voltage; avoids unnecessary power loss or false triggering in standby. |
| Response Time | <1 ns - Enables suppression of sub-nanosecond ESD events (IEC 61000-4-2) without allowing damaging overshoot. |
| UL Recognition | UL 497B certified - Validated for use in isolated loop circuits including telecom and process control interfaces. |
Pinout & Package
Package: SMB (Case 403C), surface-mount, Pb-free, void-free thermosetting plastic housing with modified L-bend leads. Mounting position is unrestricted; polarity band is not marked due to bidirectional symmetry.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode / Anode | Bidirectional terminal pair | No polarity marking required; either end connects to protected line, other to ground-enables symmetric clamping in AC or floating systems. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive underhood and chassis applications requiring extended temperature operation (−65 °C to +150 °C). |
| ESD rating >16 kV HBM | Withstands human-body-model discharges without degradation-critical for assembly-line handling and field-replaceable modules. |
| Low clamping ratio (VC/VBR ≈ 1.38) | Minimizes voltage overshoot relative to breakdown point, reducing stress margin requirements on downstream ICs. |
| UL 497B recognition | Approved for use in safety-critical isolated loop protection circuits-including analog sensor inputs and 4–20 mA transmitters. |
| Thermal resistance RJA | 226 °C/W - Enables stable operation on standard FR-4 PCBs using ON Semiconductor's recommended 403A footprint. |
Applications
| Automotive Power Distribution | Industrial PLC Analog Inputs |
|---|---|
Use Scenario: Protection of 24 V battery-fed ECUs against load dump and alternator ripple transients. IC Role / Device Role / Timing Role: Shunt TVS diode placed between power rail and chassis ground to clamp surges exceeding 38.9 V. Use Value: Prevents latch-up or permanent damage to microcontrollers and CAN transceivers during ISO 7637-2 Pulse 5a events. |
Use Scenario: Guarding 4–20 mA current-loop sensors connected to programmable logic controller (PLC) input cards. IC Role / Device Role / Timing Role: Bidirectional clamping element across loop terminals to absorb induced surges from nearby motor drives. Use Value: Maintains signal integrity and prevents false tripping while meeting UL 497B isolation barrier requirements. |
| Medical Equipment Power Rails | Telecom Line Interface Cards |
Use Scenario: Surge protection on auxiliary 24 V DC supplies powering imaging subsystems and patient monitors. IC Role / Device Role / Timing Role: Primary overvoltage clamp on secondary-side power distribution network. Use Value: Ensures compliance with IEC 60601-1 creepage/clearance and transient immunity requirements without adding series impedance. |
Use Scenario: Front-end protection for Ethernet PHY power and bias lines in remote radio units and base station backhaul interfaces. IC Role / Device Role / Timing Role: Low-capacitance (366 pF) TVS placed adjacent to connector to suppress lightning-induced common-mode surges. Use Value: Limits voltage excursion to ≤38.9 V during 10/1000 µs surges while avoiding signal distortion on 100BASE-TX lines. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SZ1SMB24AT3G | Same electrical specs and SMB package; lacks "C" suffix indicating tighter VBR tolerance (±5% vs ±10% for non-C variants). | Acceptable where ±10% VBR variation is permissible; not recommended for precision clamping thresholds. | Select SZ1SMB24CAT3G when guaranteed minimum VBR ≥28.11 V is required for margin-critical designs. |
| SMAJ24A | Lower peak power (400 W), higher clamping voltage (43.5 V @ 9.2 A), same VRWM and SMB package. | Suitable only for lower-energy transients; insufficient for IEC 61000-4-5 Level 4 or ISO 7637-2 Pulse 5a. | Choose SZ1SMB24CAT3G when 600 W surge capability and 38.9 V clamping are mandatory for system-level compliance. |
Compared with SZ1SMB24AT3G and SMAJ24A, the SZ1SMB24CAT3G delivers tighter VBR control and 50% higher surge power handling-enabling smaller safety margins and broader compliance coverage in automotive and industrial designs.
Availability
SZ1SMB24CAT3G is available at Aetrix Electronics and suitable for automotive ECUs, industrial PLC analog inputs, medical power supplies, telecom line interfaces, and process control instrumentation requiring stable component supply across multi-year production cycles.
Supply support for SZ1SMB24CAT3G 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 supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The SZ1SMBxxCAT3G series belongs to onsemi's transient voltage suppressor product line, engineered specifically for high-reliability, AEC-Q101-compliant overvoltage protection in harsh-environment applications including vehicle electrification and factory automation.
FAQ
What is the breakdown voltage specification for SZ1SMB24CAT3G?
The SZ1SMB24CAT3G has a minimum breakdown voltage (VBR) of 28.11 V at 1 mA test current, a nominal value of 28.11 V, and a maximum of 29.5 V. This ±5% tolerance (denoted by the "C" suffix) ensures predictable clamping onset in precision protection circuits where margin control is critical.
Is SZ1SMB24CAT3G suitable for automotive applications?
Yes, SZ1SMB24CAT3G is AEC-Q101 qualified and PPAP capable, with an operating temperature range of −65 °C to +150 °C. Its UL 497B recognition and 600 W surge rating make it appropriate for protecting 24 V automotive subsystems against load dump and ISO 7637-2 transients.
What does the "SZ" prefix indicate in SZ1SMB24CAT3G?
The "SZ" prefix identifies parts manufactured under onsemi's automotive-grade process flow, with enhanced site controls, change management, and traceability. It signifies compliance with AEC-Q101 stress testing and PPAP documentation requirements-not just packaging or screening differences.
How does the clamping voltage of SZ1SMB24CAT3G compare to its working voltage?
SZ1SMB24CAT3G has a 24 V working peak reverse voltage (VRWM) and clamps to 38.9 V at 15.4 A peak pulse current. This 62% overvoltage margin allows safe operation across normal 24 V rail tolerances while limiting protected circuit stress during surge events.
Does SZ1SMB24CAT3G require polarity-aware PCB layout?
No-SZ1SMB24CAT3G is a bidirectional TVS diode with symmetrical avalanche characteristics. Its SMB package has no polarity marking, and either terminal may connect to the protected line or ground, simplifying layout and eliminating orientation errors during automated assembly.
SZ1SMB24CAT3G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-214AA, SMB
- Series:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 24V
- Voltage - Breakdown (Min):
- 26.7V
- Voltage - Clamping (Max) @ Ipp:
- 38.9V
- Current - Peak Pulse (10/1000µs):
- 15.4A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- 366pF @ 1MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AA (SMB)
SZ1SMB24CAT3G FAQ
1.How can I place an order for SZ1SMB24CAT3G through Aetrix?
Please submit a Request for Quotation (RFQ) for SZ1SMB24CAT3G 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 SZ1SMB24CAT3G reliable?
The price and inventory of SZ1SMB24CAT3G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SZ1SMB24CAT3G is usually 5 days.
3.What payment methods are accepted for SZ1SMB24CAT3G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SZ1SMB24CAT3G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SZ1SMB24CAT3G?
SZ1SMB24CAT3G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SZ1SMB24CAT3G 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 SZ1SMB24CAT3G?
For technical support, including SZ1SMB24CAT3G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SZ1SMB24CAT3G requirements.
6.How does Aetrix verify that SZ1SMB24CAT3G is sourced from the original manufacturer or authorized distributors?
All SZ1SMB24CAT3G 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 SZ1SMB24CAT3G meets industry standards.
7.What is the process for return or replacement of SZ1SMB24CAT3G?
All SZ1SMB24CAT3G units undergo pre-shipment inspection (PSI). If there is an issue with SZ1SMB24CAT3G, 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 SZ1SMB24CAT3G part is unused and in its original packaging.
Return procedure for SZ1SMB24CAT3G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SZ1SMB24CAT3G 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…
