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Nexperia USA Inc. BZX84W-B3V9F
- Part No.:
- BZX84W-B3V9F
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-B3V9F.pdf
- Description:
- DIODE ZENER 3.9V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:7,439
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Product details
Overview
BZX84W-B3V9F from Nexperia is a ±2 % tolerance Zener diode in SOT323 (SC-70) package, rated for 3.9 V nominal regulation voltage at 5 mA, with 275 mW total power dissipation and 3 µA reverse current at VR = 1 V. It serves as a precision voltage reference or shunt regulator in low-power analog signal conditioning and power rail stabilization circuits.
For engineers reviewing the BZX84W-B3V9F datasheet, BZX84W-B3V9F pinout, BZX84W-B3V9F application, or BZX84W-B3V9F equivalent, key selection criteria include Zener voltage tolerance, differential resistance (90 Ω at 5 mA), thermal coefficient (−2.5 mV/K), junction-to-ambient thermal resistance (455 K/W), and SOT323 footprint compatibility for high-density PCB layouts.
Technical Context
This device operates in reverse-bias breakdown mode to maintain stable voltage across its cathode-anode terminals under varying load currents. Its −2.5 mV/K temperature coefficient ensures predictable drift over −55 °C to +150 °C ambient range, and its 90 Ω differential resistance minimizes output voltage variation with current changes up to 200 mA forward limit.
The SOT323 package features a not-connected (n.c.) terminal (Pin 2), enabling mechanical stability without electrical function-distinct from dual-anode or dual-cathode configurations. Thermal performance is specified for FR4 PCB mounting with single-sided copper, defining real-world derating curves for continuous operation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 3.9 V nominal at IZ = 5 mA; tight ±2 % tolerance enables accurate 3.3 V rail clamping or reference generation. |
| Differential Resistance (rdif) | 90 Ω max at IZ = 5 mA; limits output voltage shift to ≤0.45 V per 5 mA load change. |
| Reverse Current (IR) | 3 µA max at VR = 1 V; ensures minimal leakage in standby or low-power monitoring circuits. |
| Total Power Dissipation (Ptot) | 275 mW at Tamb = 25 °C on FR4 PCB; supports sustained regulation in compact consumer and industrial modules. |
| Thermal Resistance (Rth(j-a)) | 455 K/W; requires ≥10 °C/W board-level heatsinking to sustain >100 mW at 85 °C ambient. |
| Forward Voltage (VF) | 0.9 V max at IF = 10 mA; allows use as low-drop rectifier or ESD clamp in bidirectional protection schemes. |
| Junction Temperature (Tj) | 150 °C max; defines absolute upper limit for reliability under surge or transient overload conditions. |
Pinout & Package
SOT323 (SC-70) surface-mount plastic package with 3 leads, 1.3 mm × 1.8 mm body size, and 0.65 mm lead pitch. Designed for reflow soldering using standard footprint per Figure 9 (2.65 mm × 2.35 mm pad layout).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Connected to lower-potential node; reverse-biased during regulation; carries full load current in shunt configuration. |
| 2 | Not Connected (n.c.) | Mechanical support only; must remain unconnected in PCB layout to avoid parasitic coupling or shorting. |
| 3 | Cathode (K) | Connected to regulated voltage node; source of Zener current; polarity critical for correct biasing. |
Key Features
| Feature | Design Value |
|---|---|
| ±2 % Zener voltage tolerance | Enables direct replacement in 3.3 V LDO feedback networks without recalibration or resistor trimming. |
| Low differential resistance (90 Ω) | Reduces output impedance by >3× versus ±5 % variants, improving line regulation in battery-powered sensors. |
| −2.5 mV/K temperature coefficient | Matches typical silicon sensor drift, simplifying temperature-compensated reference designs without external compensation. |
| 275 mW power rating on FR4 | Supports 10 mA regulation current at 27.5 V input differential-sufficient for USB-C PD auxiliary rails. |
| SOT323 footprint compatibility | Shares land pattern with BZX84-C series and many logic-level MOSFETs, enabling reuse across mixed-signal boards. |
Applications
| Power Rail Clamping | ADC Reference Stabilization |
|---|---|
|
Use Scenario: Protecting 3.3 V microcontroller I/O pins from transient overvoltage during hot-plug events in industrial gateways. IC Role / Device Role / Timing Role: Shunt regulator clamping voltage between I/O line and ground, conducting excess current above 3.9 V. Use Value: Limits peak voltage to 4.2 V (including dynamic overshoot), preventing latch-up while drawing <1 mA standby leakage. |
Use Scenario: Providing stable reference voltage for 12-bit SAR ADC in portable medical pulse oximeters. IC Role / Device Role / Timing Role: Low-noise Zener reference source replacing higher-cost bandgap ICs in low-sample-rate (<1 kSPS) acquisition. Use Value: Delivers 3.9 V ±0.08 V over 0–70 °C, reducing ADC INL error by 0.5 LSB compared to resistor-divider references. |
| Low-Power Sensor Biasing | Signal Level Translation |
|
Use Scenario: Biasing thermistor bridge outputs in HVAC room temperature sensors powered by coin-cell batteries. IC Role / Device Role / Timing Role: Precision voltage source establishing common-mode level for instrumentation amplifier inputs. Use Value: Draws only 3 µA at 1 V reverse bias, extending 10-year battery life while maintaining ±0.1 °C measurement accuracy. |
Use Scenario: Translating 5 V logic signals to 3.3 V levels for FPGA configuration interfaces in telecom baseband modules. IC Role / Device Role / Timing Role: Passive level shifter using forward conduction (VF = 0.9 V) and reverse Zener action (VZ = 3.9 V). Use Value: Achieves <5 ns propagation delay with no active components, eliminating timing skew in synchronous clock domains. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84-C3V9 | ±5 % tolerance (3.7–4.1 V), 95 Ω rdif, −2.5 mV/K SZ | Higher voltage spread increases ADC reference uncertainty by ±0.2 LSB; acceptable for non-critical biasing. | Select when cost sensitivity outweighs regulation precision; same SOT323 footprint and thermal behavior. |
| MMSZ4685 | ±5 % tolerance, 3.9 V nominal, 500 mW Ptot, DO-213AC package | Larger package increases board area by 4×; higher power rating unnecessary for sub-100 mW applications. | Choose only if legacy through-hole compatibility or >300 mW surge handling is required; not drop-in SMT replacement. |
Compared with BZX84W-B3V9F, BZX84-C3V9 trades tighter voltage control for lower unit cost in non-critical regulation, while MMSZ4685 sacrifices miniaturization for higher surge robustness-neither matches the 3.9 V ±2 % + SOT323 combination for space-constrained precision analog designs.
Availability
BZX84W-B3V9F is available at Aetrix Electronics and suitable for power rail clamping, ADC reference stabilization, and low-power sensor biasing requiring stable component supply across automotive infotainment, industrial IoT edge nodes, and portable medical devices.
Supply support for BZX84W-B3V9F 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 focused on essential efficiency technologies, delivering high-performance, reliable discrete, logic, and MOSFET solutions for automotive, industrial, and consumer markets.
The BZX84W series targets high-volume, space-constrained applications needing precision Zener regulation in ultra-small packages-designed specifically for modern SMT manufacturing and miniaturized power management subsystems.
FAQ
What is the maximum continuous Zener current for BZX84W-B3V9F at 70 °C ambient?
At 70 °C ambient, derating applies: Ptot = 275 mW × (1 − (70 − 25)/125) = 165 mW. With VZ = 3.9 V, maximum continuous Zener current is 165 mW ÷ 3.9 V ≈ 42 mA. This assumes standard FR4 mounting per datasheet condition.
Can BZX84W-B3V9F be used in avalanche mode for ESD protection?
No-it is not characterized or qualified for ESD protection. Its 40 W non-repetitive peak power (PZSM) applies only to controlled square-wave surges (tp = 100 µs), not IEC 61000-4-2 transients. Dedicated TVS diodes like PESD5V0S1BA are required for certified ESD clamping.
Does Pin 2 require grounding or can it float?
Pin 2 is explicitly marked "not connected" in the datasheet and must remain unconnected in both schematic and layout. Grounding it introduces parasitic capacitance (>1 pF) and may cause unexpected coupling in RF-sensitive circuits; floating is mandatory per Nexperia's pinning specification.
How does the −2.5 mV/K temperature coefficient affect regulation at 100 °C junction temperature?
From 25 °C to 100 °C ΔT = 75 K, so voltage shift = −2.5 mV/K × 75 K = −187.5 mV. Regulation voltage drops from 3.900 V to ~3.713 V. This is fully specified and repeatable-no additional calibration needed for applications tolerating ±5 % total variation.
BZX84W-B3V9F 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):
- 3.9 V
- Tolerance:
- ±2%
- Power - Max:
- 275 mW
- Impedance (Max) (Zzt):
- 90 Ohms
- Current - Reverse Leakage @ Vr:
- 3 µA @ 1 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-B3V9F FAQ
1.How can I place an order for BZX84W-B3V9F through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-B3V9F 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-B3V9F reliable?
The price and inventory of BZX84W-B3V9F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX84W-B3V9F is usually 5 days.
3.What payment methods are accepted for BZX84W-B3V9F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-B3V9F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-B3V9F?
BZX84W-B3V9F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-B3V9F 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-B3V9F?
For technical support, including BZX84W-B3V9F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-B3V9F requirements.
6.How does Aetrix verify that BZX84W-B3V9F is sourced from the original manufacturer or authorized distributors?
All BZX84W-B3V9F 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-B3V9F meets industry standards.
7.What is the process for return or replacement of BZX84W-B3V9F?
All BZX84W-B3V9F units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-B3V9F, 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-B3V9F part is unused and in its original packaging.
Return procedure for BZX84W-B3V9F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-B3V9F 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
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