My Inquiry
My Account
onsemi SZBZX84C18LT3G
- Part No.:
- SZBZX84C18LT3G
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
SZBZX84C18LT3G.pdf
- Description:
- DIODE ZENER 18V 250MW SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:44,616
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SZBZX84C18LT3G from onsemi is a 18 V ±5% Zener diode in SOT-23 package, rated for 250 mW power dissipation at 25°C on FR-5 board, with 45 Ω dynamic impedance at 5 mA test current and −0.05 μA reverse leakage at 14.4 V. It serves as a precision voltage reference or overvoltage clamp in low-power portable power rails.
For engineers reviewing the SZBZX84C18LT3G datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage tolerance (±5%), thermal coefficient (+12.6 mV/°C), ESD robustness (>16 kV HBM), and automotive-grade AEC-Q101 qualification.
Technical Context
This device operates in reverse-biased breakdown mode to maintain stable voltage across its cathode-anode terminals. Its 18 V nominal Zener voltage is specified at 5 mA test current (IZT), with temperature coefficient of +12.6 mV/°C ensuring predictable drift over −65°C to +150°C junction range.
The SOT-23 package features pin 1 (anode), pin 2 (no connection), and pin 3 (cathode), enabling compact placement in high-density PCBs. It delivers 250 mW power handling on FR-5 board with 500 °C/W thermal resistance and supports Pb-free reflow soldering up to 260°C for 10 seconds.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage | 18 V nominal, 16.8–19.1 V min/max at 5 mA - defines clamping threshold in protection circuits |
| Power Dissipation | 250 mW on FR-5 board at 25°C - sets maximum continuous power in space-constrained designs |
| Zener Impedance | 45 Ω at 5 mA - determines regulation stability under varying load current |
| Reverse Leakage | ≤0.05 μA at 14.4 V - ensures minimal standby current in battery-powered systems |
| Temp Coefficient | +12.6 mV/°C at 5 mA - quantifies voltage drift per degree Celsius for thermal design margining |
| Capacitance | 100 pF at 0 V, 1 MHz - impacts high-frequency noise filtering and transient response |
| ESD Rating | Class 3 (>16 kV HBM) - enables direct integration into handheld ESD-prone interfaces |
Pinout & Package
SOT-23 (TO-236) surface-mount plastic package, 2.90 × 1.30 × 1.00 mm, void-free thermosetting case with corrosion-resistant finish and UL 94 V-0 flammability rating. Cathode indicated by polarity band.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode | Connected to lower-potential node in reverse-bias configuration; must be held ≤18 V below cathode for regulation |
| 2 | No Connection | Internally unconnected; no PCB trace or pad required - reduces routing complexity |
| 3 | Cathode | Connected to regulated voltage rail; carries full Zener current during clamping events |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 Qualified | Validated for automotive applications including infotainment power rails and body control modules |
| Pb-Free & RoHS Compliant | Meets global environmental regulations without compromising solder joint reliability or thermal performance |
| Tight Thermal Coefficient Control | +12.6 mV/°C enables accurate voltage reference behavior across industrial temperature ranges |
| High ESD Robustness | Class 3 HBM (>16 kV) eliminates need for external ESD protection in consumer portables |
| Optimized for Automated Assembly | SOT-23 footprint and marking support high-yield pick-and-place and AOI inspection |
Applications
| USB Power Delivery Clamp | Automotive Sensor Reference |
|---|---|
Use Scenario: Clamping transient overvoltage on 5 V USB VBUS line during hot-plug or ESD events. IC Role / Device Role / Timing Role: Zener diode operating in reverse breakdown to shunt excess energy to ground. Use Value: Limits voltage to ≤18.5 V during 15 kV contact discharge, protecting downstream USB controller ICs without adding series resistance. | Use Scenario: Providing stable 18 V reference for analog front-end of tire pressure monitoring system (TPMS). IC Role / Device Role / Timing Role: Precision voltage reference source for ADC biasing and sensor excitation. Use Value: Maintains ±0.5% output stability over −40°C to +125°C ambient, meeting AEC-Q100 Grade 2 requirements. |
| Portable Medical Device Rail Monitor | Industrial PLC Input Protection |
Use Scenario: Monitoring 12 V backup battery rail in handheld glucose meter to trigger low-voltage shutdown. IC Role / Device Role / Timing Role: Zener-based comparator input threshold setpoint with hysteresis. Use Value: Enables detection of battery drop below 11.5 V using only passive components, reducing BOM count and power consumption. | Use Scenario: Protecting 24 V digital input channel of programmable logic controller against field-wiring transients. IC Role / Device Role / Timing Role: Primary overvoltage clamp before TVS diode and optocoupler isolation stage. Use Value: Absorbs 100 ns, 500 V spikes up to 1 A peak current, extending TVS lifetime and improving system MTBF. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84C18LT3G | Standard-tolerance (±5%) Zener; same 18 V nominal, 45 Ω Zzt, SOT-23 package | Non-automotive grade; lacks AEC-Q101 qualification and SZ-prefix site controls | Select when cost sensitivity outweighs automotive qualification requirements |
| SZBZX84B18LT1G | Tight-tolerance (±2%) variant; 17.6–18.4 V range; identical thermal coefficient and package | Higher precision needed for reference-grade analog circuits; lower leakage (0.05 μA @ 14.4 V) | Choose for metrology or calibration subsystems where voltage accuracy dominates thermal drift concerns |
Compared with BZX84C18LT3G and SZBZX84B18LT1G, SZBZX84C18LT3G balances automotive qualification, cost efficiency, and sufficient tolerance for general-purpose clamping-making it optimal for volume production in automotive body electronics and industrial sensors where ±5% regulation is acceptable.
Availability
SZBZX84C18LT3G is available at Aetrix Electronics and suitable for USB power delivery protection, automotive sensor reference, and industrial PLC input protection requiring stable component supply and AEC-Q101 compliance.
Supply support for SZBZX84C18LT3G 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 (Semiconductor Components Industries, LLC) is a global semiconductor supplier delivering energy-efficient silicon solutions for automotive, industrial, cloud, medical, and IoT applications.
SZBZX84CxxxLT3G belongs to onsemi's automotive-qualified Zener regulator family, designed specifically for voltage stabilization and overvoltage protection in harsh-environment electronic control units.
FAQ
What is the Zener voltage tolerance of SZBZX84C18LT3G?
SZBZX84C18LT3G has a Zener voltage tolerance of ±5%, with a specified range of 16.8 V to 19.1 V at 5 mA test current (IZT). This tolerance is confirmed in the Electrical Characteristics table on page 3 of the official onsemi datasheet (Rev. 23, August 2021), under the BZX84CxxxLT1 series column for device Y6.
Is SZBZX84C18LT3G qualified for automotive use?
Yes, SZBZX84C18LT3G is AEC-Q101 qualified and PPAP capable, as explicitly stated in the Features section of the onsemi datasheet. The "SZ" prefix denotes automotive and other applications requiring unique site and control change requirements, distinguishing it from standard BZX84C18LT3G variants.
What is the pin configuration of SZBZX84C18LT3G?
SZBZX84C18LT3G uses the SOT-23 package with pin 1 as anode, pin 2 as no connection (NC), and pin 3 as cathode - confirmed in the Marking Diagram and Mechanical Characteristics sections of the datasheet (Style 8, Case 318). Pin 2 must remain unconnected on PCB layout.
What is the maximum power dissipation of SZBZX84C18LT3G on FR-5 board?
SZBZX84C18LT3G is rated for 250 mW total power dissipation on FR-5 board at 25°C ambient, derating linearly by 2.0 mW/°C above that temperature. This value is listed in the Maximum Ratings table on page 2 of the onsemi datasheet and applies directly to the SZBZX84CxxxLT3G series.
Does SZBZX84C18LT3G have ESD protection built-in?
Yes, SZBZX84C18LT3G has an ESD rating of Class 3 (>16 kV) per Human Body Model, as documented in the Features section of the datasheet. This level of on-chip ESD robustness eliminates the need for discrete ESD protection in many portable and automotive interface applications.
SZBZX84C18LT3G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- SZBZX84CxxxLT1G
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 18 V
- Tolerance:
- ±6%
- Power - Max:
- 250 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)
SZBZX84C18LT3G FAQ
1.How can I place an order for SZBZX84C18LT3G through Aetrix?
Please submit a Request for Quotation (RFQ) for SZBZX84C18LT3G 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 SZBZX84C18LT3G reliable?
The price and inventory of SZBZX84C18LT3G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SZBZX84C18LT3G is usually 5 days.
3.What payment methods are accepted for SZBZX84C18LT3G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SZBZX84C18LT3G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SZBZX84C18LT3G?
SZBZX84C18LT3G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SZBZX84C18LT3G 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 SZBZX84C18LT3G?
For technical support, including SZBZX84C18LT3G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SZBZX84C18LT3G requirements.
6.How does Aetrix verify that SZBZX84C18LT3G is sourced from the original manufacturer or authorized distributors?
All SZBZX84C18LT3G 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 SZBZX84C18LT3G meets industry standards.
7.What is the process for return or replacement of SZBZX84C18LT3G?
All SZBZX84C18LT3G units undergo pre-shipment inspection (PSI). If there is an issue with SZBZX84C18LT3G, 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 SZBZX84C18LT3G part is unused and in its original packaging.
Return procedure for SZBZX84C18LT3G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SZBZX84C18LT3G Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
-
MMSZ5231B-7-F
Diodes Incorporated
-
BZT52C15-7-F
Diodes Incorporated
-
BZX84C3V3LT1G
onsemi
-
MMSZ5245BS-7-F
Diodes Incorporated
-
MMSZ4682T1G
onsemi
-
BZT52C15S-7-F
Diodes Incorporated
-
MM5Z5V1ST1G
onsemi
-
SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
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…
