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onsemi SZ1SMA5921BT3G
- Part No.:
- SZ1SMA5921BT3G
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SZ1SMA5921BT3G.pdf
- Description:
- DIODE ZENER 6.8V 1.5W SMA
- Quantity:
- Payment:
- Shipping:
Inventory:9,644
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Product details
Overview
SZ1SMA5921BT3G from onsemi is a 1.5 W surface-mount Zener diode with nominal reverse breakdown voltage of 6.8 V, maximum zener impedance of 55.1 Ω at 5.2 mA test current, and leakage current ≤2.5 μA at 5.2 V reverse voltage. It serves as a precision voltage reference or overvoltage clamp in power supply regulation and ESD-protected signal conditioning circuits.
For engineers reviewing the SZ1SMA5921BT3G datasheet, pinout, applications, or equivalent options, key selection criteria include its AEC-Q101 qualification, ±5% voltage tolerance, 16 kV HBM ESD rating, and SMA package compatibility with automated SMT assembly for automotive and industrial control systems.
Technical Context
This device operates as a two-terminal voltage-regulating diode, conducting in reverse bias above its specified zener voltage (6.46–7.14 V) while maintaining stable voltage across load variations. Its thermal resistance junction-to-lead is 50 °C/W, enabling 1.5 W dissipation at 75 °C lead temperature with defined derating above that point.
The SZ1SMA5921BT3G features flat handling surfaces for accurate placement, Pb-free construction compliant with RoHS, and UL 94 V-0 flammability rating. Its cathode is marked by a molded band, and it supports top-slide or bottom-board mounting per case 403D mechanical outline.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 6.46–7.14 V @ IZT = 5.2 mA - defines regulated output range under standard test conditions |
| Power Dissipation (PD) | 1.5 W @ TL = 75°C - maximum continuous power handling with zero-lead-length thermal condition |
| Zener Impedance (ZZT) | 55.1 Ω max @ IZT = 5.2 mA - indicates voltage regulation stability under nominal bias |
| Leakage Current (IR) | ≤2.5 μA @ VR = 5.2 V - ensures minimal standby current in clamping or reference applications |
| ESD Rating | Class 3 (>16 kV) HBM - provides robust electrostatic discharge immunity without external protection |
| Operating Temp | −65 to +150 °C - supports deployment in under-hood automotive and wide-temperature industrial environments |
Pinout & Package
SMA package (Case 403D), surface-mount, low-profile plastic housing with void-free transfer-molded construction and corrosion-resistant solderable leads. Cathode identified by molded polarity band.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (Band End) | Reverse-biased terminal | Connected to higher-potential node in zener regulation; determines polarity of voltage reference or clamp |
| Anode | Forward-biased terminal | Connected to lower-potential node; completes current path during reverse conduction or forward surge events |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 Qualified | Validated for automotive-grade reliability including temperature cycling, humidity, and mechanical shock testing |
| 16 kV HBM ESD Rating | Eliminates need for discrete ESD protection in many I/O and sensor interface designs |
| Pb-Free & RoHS Compliant | Meets global environmental compliance requirements without compromising solder joint integrity |
| Flat Handling Surface | Enables high-accuracy pick-and-place placement in automated SMT lines with <±0.1 mm positional tolerance |
Applications
| Automotive Body Control Module (BCM) | Industrial PLC Analog Input Protection |
|---|---|
Use Scenario: Clamping transient voltages on LIN bus or sensor supply lines exposed to load-dump or inductive switching noise. IC Role / Device Role / Timing Role: Zener voltage clamp protecting downstream MCU GPIOs and analog front-end circuitry. Use Value: Prevents latch-up or permanent damage by limiting voltage to ≤7.14 V during 100 V/10 ms transients per ISO 7637-2 Pulse 5a. | Use Scenario: Stabilizing reference voltage for 4–20 mA loop-powered transmitter ICs operating in harsh factory environments. IC Role / Device Role / Timing Role: Precision shunt voltage reference providing stable 6.8 V bias for op-amp and ADC circuits. Use Value: Maintains ±5% regulation accuracy across −40 to +125 °C ambient, ensuring consistent 16-bit ADC full-scale calibration. |
| Medical Patient Monitor Power Sequencing | Consumer Smart Home Sensor Node |
Use Scenario: Providing isolated, low-noise 6.8 V bias for analog signal conditioning stages in battery-backed ECG front-ends. IC Role / Device Role / Timing Role: Low-leakage (<2.5 μA) voltage reference enabling microamp-level sleep current budgets. Use Value: Extends battery life beyond 72 hours in standby mode while preserving fast wake-up response via stable reference startup. | Use Scenario: Overvoltage protection for USB-C PD negotiation ICs interfacing with variable-input wall adapters. IC Role / Device Role / Timing Role: Fast-response clamp absorbing 10/1000 μs surges up to 1.5 W peak power without degradation. Use Value: Survives >10,000 surge events per IEC 61000-4-5 Level 3 without parameter shift, reducing field failure rate by >99.5%. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84-C6V8LT1G | 0.3 W power rating, SOT-23 package, 6.46–7.14 V range, 80 Ω ZZT @ 5 mA | Lower power handling limits use to low-current references or signal-level clamping only | Select when board space is constrained and dissipation remains below 300 mW |
| MMSZ5233B-TP | 500 mW rating, SOD-123 package, 6.46–7.14 V range, 100 Ω ZZT @ 20 mA | Higher ZZT reduces regulation precision; not AEC-Q101 qualified | Choose for cost-sensitive consumer applications where automotive qualification is unnecessary |
Compared with BZX84-C6V8LT1G and MMSZ5233B-TP, the SZ1SMA5921BT3G delivers 3× higher power capability, superior zener impedance, and automotive-grade reliability-making it the preferred choice for mission-critical voltage regulation where thermal margin and long-term stability are design priorities.
Availability
SZ1SMA5921BT3G is available at Aetrix Electronics and suitable for automotive body electronics, industrial programmable logic controllers, and medical monitoring equipment requiring stable component supply with full traceability and lifecycle management.
Supply support for SZ1SMA5921BT3G 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 is a global semiconductor supplier delivering energy-efficient silicon solutions for automotive, industrial, cloud, medical, and IoT applications.
The SZ1SMA59xxBT3G series was engineered specifically for high-reliability voltage regulation in automotive and industrial systems, combining AEC-Q101 qualification with robust thermal performance and ESD resilience.
FAQ
What is the nominal zener voltage of the SZ1SMA5921BT3G?
The SZ1SMA5921BT3G has a nominal zener voltage of 6.8 V, with guaranteed minimum and maximum values of 6.46 V and 7.14 V respectively at a test current of 5.2 mA. This ±5% tolerance is confirmed in the Electrical Characteristics table on page 2 of the official onsemi datasheet.
Is the SZ1SMA5921BT3G qualified for automotive applications?
Yes, the SZ1SMA5921BT3G carries the "SZ" prefix indicating AEC-Q101 qualification and PPAP capability. It meets automotive reliability standards including temperature cycling, mechanical shock, and humidity testing, making it suitable for under-hood and chassis-mounted electronic control units.
What is the maximum power dissipation for the SZ1SMA5921BT3G?
The SZ1SMA5921BT3G is rated for 1.5 W DC power dissipation at a lead temperature of 75 °C. Above this temperature, power must be linearly derated at 20 mW/°C, reaching zero dissipation at 150 °C junction temperature per the Maximum Ratings table.
Does the SZ1SMA5921BT3G have ESD protection built-in?
Yes, the SZ1SMA5921BT3G features an ESD rating of Class 3 (>16 kV) per the Human Body Model (HBM), as stated in the Features section of the onsemi datasheet. This eliminates the need for additional discrete ESD components in many I/O protection schemes.
What package type does the SZ1SMA5921BT3G use?
The SZ1SMA5921BT3G uses the SMA (DO-214AC) surface-mount package, also designated Case 403D. It features a low-profile plastic body with a molded cathode band, and is supplied in tape-and-reel format with 5,000 units per reel.
SZ1SMA5921BT3G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- SZ1SMA59xxBT3G
- Package/Case:
- DO-214AC, SMA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 6.8 V
- Tolerance:
- ±5%
- Power - Max:
- 1.5 W
- Impedance (Max) (Zzt):
- 2.5 Ohms
- Current - Reverse Leakage @ Vr:
- 2.5 µA @ 5.2 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 200 mA
- Operating Temperature:
- -65°C ~ 150°C
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMA
SZ1SMA5921BT3G FAQ
1.How can I place an order for SZ1SMA5921BT3G through Aetrix?
Please submit a Request for Quotation (RFQ) for SZ1SMA5921BT3G 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 SZ1SMA5921BT3G reliable?
The price and inventory of SZ1SMA5921BT3G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SZ1SMA5921BT3G is usually 5 days.
3.What payment methods are accepted for SZ1SMA5921BT3G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SZ1SMA5921BT3G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SZ1SMA5921BT3G?
SZ1SMA5921BT3G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SZ1SMA5921BT3G 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 SZ1SMA5921BT3G?
For technical support, including SZ1SMA5921BT3G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SZ1SMA5921BT3G requirements.
6.How does Aetrix verify that SZ1SMA5921BT3G is sourced from the original manufacturer or authorized distributors?
All SZ1SMA5921BT3G 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 SZ1SMA5921BT3G meets industry standards.
7.What is the process for return or replacement of SZ1SMA5921BT3G?
All SZ1SMA5921BT3G units undergo pre-shipment inspection (PSI). If there is an issue with SZ1SMA5921BT3G, 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 SZ1SMA5921BT3G part is unused and in its original packaging.
Return procedure for SZ1SMA5921BT3G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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