My Inquiry
My Account
Nexperia USA Inc. BZX84W-B18F
- Part No.:
- BZX84W-B18F
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-B18F.pdf
- Description:
- DIODE ZENER 18V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:8,849
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BZX84W-B18F from Nexperia is a ±2% tolerance Zener voltage regulator diode in SOT323 (SC-70) package, rated for 18 V nominal Zener voltage at 5 mA, 275 mW total power dissipation, and 225 Ω differential resistance at IZ = 5 mA - used for precision voltage reference and local regulation in compact DC-DC feedback paths.
For engineers reviewing the BZX84W-B18F datasheet, BZX84W-B18F pinout, BZX84W-B18F application, or BZX84W-B18F equivalent, key selection factors include its ±2% VZ tolerance, low 1.5 pF junction capacitance at 0 V, 14.4 mV/K temperature coefficient at 5 mA, and compatibility with reflow/wave soldering per IPC-7095 on FR4 PCBs.
Technical Context
This Zener diode operates in reverse breakdown to maintain stable voltage across load variations, with specified Zener voltage measured at IZ = 5 mA and thermal resistance Rth(j-a) = 455 K/W on standard FR4 PCB. Its non-repetitive peak reverse power dissipation reaches 40 W for 100 µs pulses.
The device exhibits a positive temperature coefficient of +14.4 mV/K at 5 mA, enabling predictable drift compensation in bias networks, and features a not-connected (n.c.) terminal (Pin 2) to support dual-anode/cathode layout flexibility in high-density routing.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage VZ | 17.6 V to 18.4 V at IZ = 5 mA - ensures tight regulation window for 18 V reference designs |
| Tolerance | ±2% (B-series) - supports high-accuracy feedback loops without post-calibration |
| Differential Resistance rdif | 225 Ω max at IZ = 5 mA - limits output impedance impact on load transient response |
| Junction Capacitance Cd | 1.5 pF at f = 1 MHz, VR = 0 V - enables use in >100 MHz noise filtering and RF decoupling |
| Forward Voltage VF | ≤0.9 V at IF = 10 mA - allows safe forward-bias testing without excessive power loss |
| Power Dissipation Ptot | 275 mW on FR4 PCB - defines maximum continuous DC/low-frequency regulation capability |
| Reverse Current IR | 50 nA at VR = 12.6 V (0.7 × VZnom) - ensures minimal leakage in standby power domains |
Pinout & Package
SOT323 (SC-70) leadless surface-mount plastic package: 1.35 mm × 1.75 mm footprint, 0.65 mm pitch, 0.9 mm height, optimized for automated placement and IPC-7095-compliant reflow.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Forward current entry point; connected to lower-potential node in Zener regulation configuration |
| 2 | Not Connected (n.c.) | Internally unconnected; electrically isolated - must remain floating or grounded per layout rules |
| 3 | Cathode (K) | Reverse-bias terminal; tied to regulated output node and feedback divider in shunt regulator topologies |
Key Features
| Feature | Design Value |
|---|---|
| ±2% Zener voltage tolerance | Enables direct replacement of higher-cost precision references in 18 V feedback networks without trimming |
| 1.5 pF junction capacitance | Minimizes high-frequency signal coupling in RF bias rails and clock line filtering applications |
| +14.4 mV/K temperature coefficient | Provides predictable, linear drift for temperature-compensated reference designs using complementary components |
| 275 mW power rating on FR4 | Supports sustained 18 V/15 mA regulation in space-constrained industrial sensor modules |
| SC-70 (SOT323) package | Reduces PCB area by 60% vs. SOT23 while maintaining compatibility with standard pick-and-place equipment |
Applications
| Industrial Sensor Signal Conditioning | USB-C Power Delivery Feedback |
|---|---|
|
Use Scenario: Stabilizing reference voltage for 16-bit ADC biasing in temperature/humidity transmitters. IC Role / Device Role / Timing Role: Shunt Zener regulator providing 18 V reference to op-amp rail-splitter and ADC VREF input. Use Value: ±2% VZ tolerance eliminates need for external trimming resistors, reducing BOM count and calibration steps. |
Use Scenario: Generating precise 18 V auxiliary supply for USB PD controller gate drivers. IC Role / Device Role / Timing Role: Local voltage clamp regulating gate drive rail in buck-boost power stage control loop. Use Value: 225 Ω rdif ensures <10 mV droop under 10 mA dynamic load, preserving PWM timing accuracy. |
| Automotive Body Control Module (Non-Safety) | IoT Node Battery Monitoring |
|
Use Scenario: Providing stable 18 V reference for LIN bus transceiver biasing in door module ECUs. IC Role / Device Role / Timing Role: Zener-based voltage supervisor for microcontroller reset threshold generation. Use Value: 1.5 pF Cd prevents coupling of LIN edge transients into reset logic, improving EMI immunity. |
Use Scenario: Regulating 18 V supply for fuel gauge IC in lithium-ion battery pack management systems. IC Role / Device Role / Timing Role: Low-leakage shunt regulator maintaining reference during deep-sleep states. Use Value: 50 nA IR at 12.6 V reduces quiescent current by >95% vs. LDO alternatives, extending shelf life. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ON Semiconductor MMBZ5245BS | 18 V ±5%, 350 mW rating, SOT-323, 100 Ω rdif, −2 mV/K TC | Higher power but looser tolerance and negative TC - requires TC compensation circuitry | Select when higher surge robustness is needed and ±5% regulation is acceptable |
| Vishay BZX84-C18 | 18 V ±5%, 300 mW, SOT-23, 40 Ω rdif, +14.4 mV/K TC | Lower rdif but larger SOT-23 footprint and same TC - better regulation but less board space efficiency | Select when lowest dynamic impedance is critical and PCB real estate permits SOT-23 |
Compared with BZX84W-B18F, MMBZ5245BS trades tighter thermal stability for reduced accuracy, while BZX84-C18 improves regulation stiffness at the cost of 40% larger footprint and no n.c. pin for routing optimization.
Availability
BZX84W-B18F is available at Aetrix Electronics and suitable for industrial sensor conditioning, USB-C power delivery feedback, automotive body control modules (non-safety), and IoT battery monitoring requiring stable component supply with guaranteed long-term continuity.
Supply support for BZX84W-B18F 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
Nexperia is a global semiconductor expert delivering high-performance, reliable discrete, logic, and MOSFET devices with focus on efficiency, miniaturization, and automotive-grade reliability.
BZX84W series belongs to Nexperia's general-purpose Zener diode product line, engineered for compact, high-frequency-stable voltage regulation in space-constrained consumer, industrial, and computing applications.
FAQ
What is the maximum reverse current specification for BZX84W-B18F at its rated Zener voltage?
The maximum reverse current (IR) is 50 nA at VR = 12.6 V (0.7 × VZnom), measured at Tj = 25 °C. This ultra-low leakage supports energy-sensitive applications like battery-backed circuits and sleep-mode regulators where standby current must remain below 100 nA.
Can BZX84W-B18F be used in high-frequency filtering applications?
Yes - its 1.5 pF junction capacitance at 0 V and 1 MHz makes it suitable for RF bypass and high-frequency noise suppression up to 500 MHz. The low Cd minimizes signal attenuation in bias tee networks and preserves integrity of fast digital clock edges near regulated rails.
How does the not-connected (n.c.) pin affect PCB layout and thermal performance?
Pin 2 is internally unconnected and must remain electrically floating or tied to ground only if required for mechanical stability; it does not contribute to thermal conduction. Thermal resistance Rth(j-a) = 455 K/W assumes standard SOT323 mounting on single-sided FR4 copper, independent of Pin 2 connection status.
Is BZX84W-B18F qualified for automotive applications?
No - this part is non-automotive qualified per Nexperia's revision history (v.2, Jan 2023). It lacks AEC-Q101 qualification and is not tested to automotive temperature, humidity, or vibration requirements. For automotive use, select Nexperia's -Q qualified variants such as BZX84W-Q18F.
BZX84W-B18F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX84W
- Package/Case:
- SC-70, SOT-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 18 V
- Tolerance:
- ±2%
- Power - Max:
- 275 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:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-323
BZX84W-B18F FAQ
1.How can I place an order for BZX84W-B18F through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-B18F 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 BZX84W-B18F reliable?
The price and inventory of BZX84W-B18F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX84W-B18F is usually 5 days.
3.What payment methods are accepted for BZX84W-B18F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-B18F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-B18F?
BZX84W-B18F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-B18F 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 BZX84W-B18F?
For technical support, including BZX84W-B18F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-B18F requirements.
6.How does Aetrix verify that BZX84W-B18F is sourced from the original manufacturer or authorized distributors?
All BZX84W-B18F 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 BZX84W-B18F meets industry standards.
7.What is the process for return or replacement of BZX84W-B18F?
All BZX84W-B18F units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-B18F, 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 BZX84W-B18F part is unused and in its original packaging.
Return procedure for BZX84W-B18F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-B18F 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
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…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
