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onsemi SZBZX84C39LT1
- Part No.:
- SZBZX84C39LT1
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
SZBZX84C39LT1.pdf
- Description:
- DIODE ZENER 39V 225MW SOT23
- Quantity:
- Payment:
- Shipping:
Inventory:27,000
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Product details
Overview
SZBZX84C39LT1 from onsemi is a 39 V, ±5% tolerance Zener diode in SOT-23 package, rated for 225 mW power dissipation at 25°C on FR-5 board, with 130 Ω dynamic impedance at 5 mA test current and 70 µA maximum reverse leakage at 31.1 V. It serves as a precision voltage reference or overvoltage clamp in portable power rails and low-power sensor interfaces.
For engineers reviewing the SZBZX84C39LT1 datasheet, pinout, applications, or equivalent options, key selection criteria include nominal Zener voltage (39 V), tolerance (±5%), thermal coefficient (+27.3 mV/°C), junction-to-ambient thermal resistance (556 °C/W), and ESD rating (>16 kV HBM).
Technical Context
This device operates as a two-terminal voltage regulator using avalanche breakdown in silicon PN junction. Its Zener voltage is specified at three test currents (2 mA, 5 mA, 20 mA), enabling stable reference generation across varying load conditions. The SOT-23 package supports automated placement and reflow soldering per JEDEC J-STD-020.
It features a cathode-anode configuration with pin 2 unconnected, exhibits a positive temperature coefficient of +27.3 mV/°C at 5 mA, and maintains ≤45 pF capacitance at 0 V bias and 1 MHz - critical for high-frequency noise suppression in feedback paths.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage | 39 V nominal, 37–41 V min/max range at 5 mA - defines clamping threshold for 3.3 V/5 V rail protection circuits |
| Power Dissipation | 225 mW on FR-5 board at 25°C - sets maximum continuous power handling without heatsinking |
| Zener Impedance | 130 Ω at 5 mA - determines regulation stiffness under dynamic load transients |
| Reverse Leakage | 70 µA max at 31.1 V - ensures minimal quiescent current in standby mode |
| Temperature Coefficient | +27.3 mV/°C at 5 mA - quantifies voltage drift over industrial temperature range (−65°C to +150°C) |
| Capacitance | 45 pF max at 0 V, 1 MHz - limits high-frequency coupling in signal path filtering |
| ESD Rating | Class 3 (>16 kV) per HBM - enables direct integration into handheld device I/O protection |
Pinout & Package
SOT-23 (TO-236) surface-mount plastic package, void-free thermosetting case with corrosion-resistant finish; cathode indicated by polarity band; 260°C max soldering temperature for 10 seconds.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode | Connected to lower-potential node in reverse-bias configuration; carries forward current during fault conduction |
| 2 | No Connection | Internally unconnected; must remain floating - no PCB trace or pad required |
| 3 | Cathode | Connected to regulated voltage node; provides reference potential for feedback or clamp function |
Key Features
| Feature | Design Value |
|---|---|
| 225 mW FR-5 power rating | Enables compact voltage regulation without external heat sinking in space-constrained PCBs |
| ±5% Zener tolerance | Supports deterministic overvoltage protection thresholds in automotive and industrial control systems |
| ESD Class 3 (>16 kV HBM) | Eliminates need for discrete ESD diodes in front-end I/O protection networks |
| AEC-Q101 qualified | Validates reliability for automotive body electronics and infotainment power management |
| Pb-free SOT-23 package | Meets RoHS compliance requirements without sacrificing thermal or mechanical performance |
Applications
| USB Power Interface Protection | Industrial Sensor Reference |
|---|---|
Use Scenario: Clamping transient surges on USB VBUS lines in portable docking stations. IC Role / Device Role / Timing Role: Two-terminal shunt regulator acting as overvoltage clamp between VBUS and GND. Use Value: Limits peak voltage to ≤41 V during ESD events while drawing <70 µA in normal operation - preserving USB enumeration integrity. |
Use Scenario: Providing stable 39 V reference for analog front-end gain calibration in pressure transducers. IC Role / Device Role / Timing Role: Precision Zener reference source for ADC biasing and offset trimming. Use Value: Delivers <±0.5% voltage stability over −40°C to +85°C due to predictable +27.3 mV/°C TC - reducing calibration frequency. |
| Automotive Body Control Module | Low-Power IoT Node Regulator |
Use Scenario: Regulating auxiliary 12 V rail for LIN bus transceivers in door module ECUs. IC Role / Device Role / Timing Role: Shunt regulator maintaining stable supply for communication ICs during battery voltage fluctuations. Use Value: Withstands 150°C junction temperature and AEC-Q101 qualification - ensuring functional safety in under-hood environments. |
Use Scenario: Generating local 3.3 V bias from coin-cell supply via resistive divider + Zener stabilization. IC Role / Device Role / Timing Role: Low-quiescent-current voltage reference enabling ultra-low-power sleep mode operation. Use Value: Draws only 70 µA leakage at 31.1 V - extending 10-year battery life in wireless sensor nodes. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84C39LT1 | Same electrical specs but non-automotive grade; lacks AEC-Q101 qualification and SZ prefix | Not suitable for automotive production; acceptable for consumer-grade prototyping | Select when cost sensitivity outweighs automotive qualification requirements |
| SZBZX84C39LT1G | Pb-free variant with identical Zener parameters, thermal specs, and AEC-Q101 status | Direct drop-in replacement where RoHS compliance is mandatory | Choose for new designs requiring lead-free assembly and full automotive traceability |
Compared with SZBZX84C39LT1, BZX84C39LT1 omits automotive qualification and site control, while SZBZX84C39LT1G adds Pb-free compliance without altering regulation performance - making the latter ideal for globally deployed automotive modules requiring both reliability and environmental compliance.
Availability
SZBZX84C39LT1 is available at Aetrix Electronics and suitable for USB interface protection, industrial sensor reference design, automotive body control modules, and low-power IoT node regulation requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for SZBZX84C39LT1 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, and cloud infrastructure markets.
SZBZX84C39LT1 belongs to the BZX84CxxxLT1 family of Zener regulators designed specifically for high-density, surface-mount voltage reference and overvoltage protection in automotive and industrial applications.
FAQ
What is the Zener voltage tolerance of SZBZX84C39LT1?
The SZBZX84C39LT1 has a standard tolerance of ±5%, meaning its Zener voltage is guaranteed between 37 V and 41 V when tested at 5 mA. This tolerance is defined per the BZX84CxxxLT1 series specification and applies across the full operating temperature range of −65°C to +150°C. The SZBZX84C39LT1 datasheet confirms this range in the Electrical Characteristics table on page 3.
Does SZBZX84C39LT1 have automotive qualification?
Yes, SZBZX84C39LT1 is AEC-Q101 qualified and PPAP capable, as explicitly stated in the "Features" section of the official datasheet. The "SZ" prefix denotes automotive and other applications requiring unique site and process controls, distinguishing it from commercial-grade BZX84C39LT1 variants. This qualification covers stress testing for temperature cycling, humidity, and mechanical shock.
What is the thermal resistance of SZBZX84C39LT1 on FR-5 board?
The junction-to-ambient thermal resistance (RJA) of SZBZX84C39LT1 is 556 °C/W when mounted on an FR-5 board, as specified in the "Maximum Ratings" table. This value assumes a standard 1.0 × 0.75 × 0.62 inch board and defines the temperature rise per watt of dissipated power - critical for calculating safe operating area in continuous-clamp applications.
How many pins does SZBZX84C39LT1 use, and what are their functions?
SZBZX84C39LT1 uses three pins in its SOT-23 package: Pin 1 is the anode, Pin 2 is internally unconnected (NC), and Pin 3 is the cathode. This pinout is confirmed in the "Electrical Characteristics" section and marking diagram of the datasheet. Pin 2 must remain unconnected on the PCB to avoid unintended parasitic paths or thermal stress.
Is SZBZX84C39LT1 RoHS compliant?
Yes, SZBZX84C39LT1 is RoHS compliant. The "G" suffix in related part numbers (e.g., SZBZX84C39LT1G) explicitly indicates Pb-free packaging, and the base SZBZX84C39LT1 is manufactured to meet RoHS Directive 2011/65/EU requirements. The datasheet states "Pb−Free Packages are Available" and confirms corrosion-resistant, lead-free finish on the SOT-23 case.
SZBZX84C39LT1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Bulk
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 39 V
- Tolerance:
- ±5%
- Power - Max:
- 225 mW
- Impedance (Max) (Zzt):
- 130 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 27.3 V
- Voltage - Forward (Vf) (Max) @ If:
- 900 mV @ 10 mA
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3 (TO-236)
SZBZX84C39LT1 FAQ
1.How can I place an order for SZBZX84C39LT1 through Aetrix?
Please submit a Request for Quotation (RFQ) for SZBZX84C39LT1 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 SZBZX84C39LT1 reliable?
The price and inventory of SZBZX84C39LT1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SZBZX84C39LT1 is usually 5 days.
3.What payment methods are accepted for SZBZX84C39LT1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SZBZX84C39LT1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SZBZX84C39LT1?
SZBZX84C39LT1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SZBZX84C39LT1 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 SZBZX84C39LT1?
For technical support, including SZBZX84C39LT1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SZBZX84C39LT1 requirements.
6.How does Aetrix verify that SZBZX84C39LT1 is sourced from the original manufacturer or authorized distributors?
All SZBZX84C39LT1 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 SZBZX84C39LT1 meets industry standards.
7.What is the process for return or replacement of SZBZX84C39LT1?
All SZBZX84C39LT1 units undergo pre-shipment inspection (PSI). If there is an issue with SZBZX84C39LT1, 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 SZBZX84C39LT1 part is unused and in its original packaging.
Return procedure for SZBZX84C39LT1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SZBZX84C39LT1 Tags
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