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onsemi SZBZX84C18LT1
- Part No.:
- SZBZX84C18LT1
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
SZBZX84C18LT1.pdf
- Description:
- DIODE ZENER 18V 225MW SOT23
- Quantity:
- Payment:
- Shipping:
Inventory:99,000
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Product details
Overview
SZBZX84C18LT1 from onsemi is a 250 mW, 18 V nominal Zener voltage regulator diode in SOT−23 package, rated for ±5% tolerance at 5 mA test current, with 45 Ω dynamic impedance and 12.6 mV/°C temperature coefficient - used for precision voltage reference and overvoltage protection in portable power rails.
For engineers reviewing the SZBZX84C18LT1 datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage tolerance, dynamic impedance at 5 mA, thermal coefficient, reverse leakage at 14.4 V, and SOT−23 footprint compatibility with high-density PCB layouts.
Technical Context
This device operates as a two-terminal silicon Zener diode with cathode-anode polarity, designed for stable reverse-biased breakdown regulation. It exhibits a nominal 18 V Zener voltage at 5 mA (IZT), with guaranteed min/max bounds of 16.8 V to 19.1 V and 20 Ω max Zener impedance at 10 mA.
The SZBZX84C18LT1 features an ESD rating >16 kV per Human Body Model, Pb-free RoHS-compliant construction, and AEC−Q101 qualification for automotive use. Its SOT−23 package supports automated assembly and delivers 250 mW dissipation on FR−5 board with 500 °C/W thermal resistance.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 16.8–19.1 V @ IZT = 5 mA - defines regulated output range under standard test conditions |
| Zener Impedance (ZZT) | 45 Ω max @ IZT = 5 mA - determines output voltage stability under load transients |
| Reverse Leakage Current | 0.05 µA @ VR = 14.4 V - ensures minimal quiescent current in standby regulation |
| Temperature Coefficient | +12.6 mV/°C @ IZT = 5 mA - quantifies voltage drift across operating temperature range |
| Power Dissipation | 250 mW on FR−5 board @ TA = 25°C - sets maximum continuous DC power handling capability |
| Capacitance | 100 pF @ VR = 0 V, f = 1 MHz - impacts high-frequency noise filtering and transient response |
| ESD Rating | Class 3 (>16 kV) HBM - enables robust handling in automated manufacturing without special ESD controls |
Pinout & Package
SOT−23 plastic surface-mount package (Case 318, Style 8), void-free thermosetting epoxy, cathode indicated by band. Dimensions: 2.90 mm × 1.30 mm × 0.95 mm (L × W × H).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode | Connected to lower-potential node in reverse-bias configuration; must be held ≤ VZ − 0.9 V during forward conduction |
| 2 | No Connection | Internally unconnected; electrically isolated - no PCB trace or pad required |
| 3 | Cathode | Connected to regulated output node; carries full Zener current and defines reference potential |
Key Features
| Feature | Design Value |
|---|---|
| AEC−Q101 qualified | Validated for automotive underhood and infotainment applications requiring PPAP documentation and process control |
| ±5% Zener voltage tolerance | Enables predictable clamping thresholds without post-production trimming in cost-sensitive consumer designs |
| 250 mW FR−5 power rating | Supports regulation of low-power sensor bias rails and microcontroller reset circuits without heatsinking |
| 16 kV HBM ESD rating | Eliminates need for external ESD protection in handheld and wearable end-equipment assembly lines |
| Pb-free / RoHS compliant | Meets global environmental compliance mandates without sacrificing electrical performance or reliability |
Applications
| Portable Power Rail Protection | Microcontroller Reset Reference |
|---|---|
Use Scenario: Clamping 18 V supply rail in Bluetooth headset battery management circuit against surge events. IC Role / Device Role / Timing Role: Two-terminal passive voltage clamp absorbing transient energy above 18 V threshold. Use Value: Prevents damage to 3.3 V LDO and BLE SoC by limiting rail excursion to ≤19.1 V with <0.05 µA leakage at 14.4 V. |
Use Scenario: Generating precise 18 V reference for RC reset timer in industrial PLC controller MCU. IC Role / Device Role / Timing Role: Stable Zener reference setting RC time constant for reliable power-on reset assertion. Use Value: Enables ±5% reset timing accuracy over −40°C to +125°C due to 12.6 mV/°C TC and 45 Ω ZZT. |
| Automotive Sensor Biasing | USB-C PD Feedback Divider |
Use Scenario: Providing stable 18 V bias to analog front-end of vehicle cabin temperature sensor. IC Role / Device Role / Timing Role: Low-leakage Zener shunt regulating bias voltage independent of load current variation. Use Value: Maintains sensor linearity with <0.05 µA IR at 14.4 V and 100 pF capacitance minimizing HF noise coupling. |
Use Scenario: Acting as upper leg in feedback divider for 20 V USB-C Power Delivery adapter output stage. IC Role / Device Role / Timing Role: Precision voltage reference element defining output setpoint via resistor ratio. Use Value: Delivers 18 V nominal reference with 16.8–19.1 V bounds, enabling ±2.5% output regulation without calibration. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84C18LT1G | Same Zener voltage range (16.8–19.1 V), identical SOT−23 package, but lacks AEC−Q101 qualification and SZ-prefix automotive traceability | Not suitable for automotive PPAP-controlled production; acceptable for commercial-grade consumer electronics | Select BZX84C18LT1G only when automotive qualification and site-specific change control are not required |
| SZBZX84B18LT1G | Tighter ±2% tolerance (17.6–18.4 V), same 45 Ω ZZT, identical AEC−Q101 status and SOT−23 footprint | Better voltage accuracy for precision references; higher cost and reduced availability vs. C-series | Choose SZBZX84B18LT1G when ±2% regulation tolerance is mandatory, e.g., in closed-loop feedback paths |
Compared with SZBZX84C18LT1, BZX84C18LT1G offers identical electrical specs but no automotive qualification, while SZBZX84B18LT1G provides tighter tolerance at the cost of narrower voltage range and higher unit price - making SZBZX84C18LT1 optimal for cost-sensitive AEC−Q101 applications where ±5% is sufficient.
Availability
SZBZX84C18LT1 is available at Aetrix Electronics and suitable for automotive infotainment systems, portable medical monitors, industrial sensor nodes, and USB-C power adapters requiring stable component supply with full AEC−Q101 traceability.
Supply support for SZBZX84C18LT1 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, sensors, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.
SZBZX84C18LT1 belongs to the SZBZX84CxxxLT1G automotive Zener regulator family, engineered for high-reliability voltage reference and overvoltage protection in space-constrained, thermally demanding environments.
FAQ
What is the Zener voltage tolerance of SZBZX84C18LT1 at 5 mA test current?
The SZBZX84C18LT1 has a nominal Zener voltage of 18 V with a guaranteed tolerance of ±5% at IZT = 5 mA, corresponding to a min/max range of 16.8 V to 19.1 V. This tolerance is specified in the Electrical Characteristics table on page 3 of the official datasheet and applies directly to the SZBZX84C18LT1 part number.
Is SZBZX84C18LT1 qualified for automotive applications?
Yes, SZBZX84C18LT1 is AEC−Q101 qualified and PPAP capable, as explicitly stated in the Features section of the datasheet. The "SZ" prefix denotes automotive-grade devices meeting unique site and process control requirements - confirming its suitability for under-hood and infotainment systems.
What is the maximum power dissipation of SZBZX84C18LT1 on FR−5 board?
SZBZX84C18LT1 is rated for 250 mW total power dissipation on FR−5 board at TA = 25°C, derating linearly by 2.0 mW/°C above that temperature. This value is listed in the Maximum Ratings table on page 2 and reflects its thermal performance in standard PCB material.
Does SZBZX84C18LT1 have a no-connect pin, and how is it identified?
Yes, SZBZX84C18LT1 has Pin 2 designated as "No Connection" - internally unconnected and electrically isolated. Per the Marking Diagram and Electrical Characteristics tables, the pinout is: Pin 1 = Anode, Pin 2 = No Connection, Pin 3 = Cathode, with cathode identified by a polarity band on the SOT−23 package.
What is the reverse leakage current specification for SZBZX84C18LT1?
SZBZX84C18LT1 specifies a maximum reverse leakage current (IR) of 0.05 µA at VR = 14.4 V, as shown in the BZX84CxxxLT1 Series Electrical Characteristics table. This low leakage ensures minimal power loss in always-on voltage reference applications.
SZBZX84C18LT1 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):
- 18 V
- Tolerance:
- ±6%
- Power - Max:
- 225 mW
- Impedance (Max) (Zzt):
- 45 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 12.6 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)
SZBZX84C18LT1 FAQ
1.How can I place an order for SZBZX84C18LT1 through Aetrix?
Please submit a Request for Quotation (RFQ) for SZBZX84C18LT1 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 SZBZX84C18LT1 reliable?
The price and inventory of SZBZX84C18LT1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SZBZX84C18LT1 is usually 5 days.
3.What payment methods are accepted for SZBZX84C18LT1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SZBZX84C18LT1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SZBZX84C18LT1?
SZBZX84C18LT1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SZBZX84C18LT1 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 SZBZX84C18LT1?
For technical support, including SZBZX84C18LT1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SZBZX84C18LT1 requirements.
6.How does Aetrix verify that SZBZX84C18LT1 is sourced from the original manufacturer or authorized distributors?
All SZBZX84C18LT1 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 SZBZX84C18LT1 meets industry standards.
7.What is the process for return or replacement of SZBZX84C18LT1?
All SZBZX84C18LT1 units undergo pre-shipment inspection (PSI). If there is an issue with SZBZX84C18LT1, 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 SZBZX84C18LT1 part is unused and in its original packaging.
Return procedure for SZBZX84C18LT1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SZBZX84C18LT1 Tags
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