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Nexperia USA Inc. BZX84W-C39X
- Part No.:
- BZX84W-C39X
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-C39X.pdf
- Description:
- DIODE ZENER 39V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:7,418
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Product details
Overview
BZX84W-C39X from Nexperia is a ±5% tolerance Zener voltage regulator diode with nominal 39 V breakdown voltage, 350 Ω differential resistance at 2 mA, 36.4 mV/K temperature coefficient, and 0.7 pF capacitance at 1 MHz - used for precision voltage reference and overvoltage clamping in low-power analog signal conditioning circuits.
For engineers reviewing the BZX84W-C39X datasheet, BZX84W-C39X pinout, BZX84W-C39X application, or BZX84W-C39X equivalent, this page delivers verified electrical parameters, SOT323 terminal mapping, thermal derating guidance, and direct substitution options for industrial power rail stabilization and ESD-protected sensor interface designs.
Technical Context
This Zener diode operates in reverse-biased breakdown mode to maintain stable voltage across its cathode-anode terminals under varying load current (IZ = 2 mA typical), with junction temperature-dependent regulation accuracy governed by its +36.4 mV/K temperature coefficient. Its low 0.7 pF capacitance enables use in high-frequency bias networks without signal distortion.
The device complies with IEC 60134 absolute maximum ratings, supports non-repetitive 40 W surge dissipation for transient suppression, and is rated for continuous 275 mW operation on FR4 PCB with single-sided copper - defining its placement constraints in thermally sensitive layouts.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 39 V nominal, ±5% tolerance - sets precise clamping threshold for 3.3 V/5 V/12 V rail protection |
| Differential Resistance (rdif) | 350 Ω at IZ = 2 mA - determines output impedance and regulation sensitivity to current variation |
| Temperature Coefficient (SZ) | +36.4 mV/K - quantifies voltage drift per degree Celsius rise, critical for temperature-stable references |
| Diode Capacitance (Cd) | 0.7 pF at f = 1 MHz, VR = 0 V - enables RF-transparent operation in high-speed signal path biasing |
| Forward Voltage (VF) | ≤ 0.9 V at IF = 10 mA - defines conduction loss during forward-biased fault conditions |
| Peak Reverse Power (PZSM) | 40 W for tp = 100 µs - specifies single-pulse surge handling capability for ESD/transient events |
| Total Power Dissipation (Ptot) | 275 mW at Tamb = 25 °C on FR4 PCB - establishes thermal design margin for steady-state operation |
Pinout & Package
Package: SOT323 (SC-70), leadless surface-mount plastic package with 3 terminals, footprint dimensions 2.2 mm × 1.35 mm × 0.95 mm (L × W × H), compatible with standard reflow soldering profiles.
| 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.) | Electrically isolated internal pad - must remain unconnected in PCB layout to avoid parasitic coupling |
| 3 | Cathode (K) | Reverse-bias voltage reference node; tied to regulated output or clamp point in circuit |
Key Features
| Feature | Design Value |
|---|---|
| ±5% Zener voltage tolerance | Enables cost-effective selection for non-critical voltage references where tight regulation is not required |
| Low 0.7 pF junction capacitance | Minimizes loading on high-frequency signal paths, supporting use in RF detector bias and clock line clamping |
| 350 Ω dynamic impedance at 2 mA | Provides predictable regulation slope for current-source-based reference designs with known load variation |
| Non-repetitive 40 W surge rating | Allows integration into I/O protection circuits without external TVS devices for moderate ESD events |
| SOT323 ultra-small footprint | Reduces board area by >50% vs. SOD-323 packages, enabling dense analog front-end layouts |
Applications
| Industrial Sensor Signal Conditioning | USB Port Overvoltage Protection |
|---|---|
|
Use Scenario: Stabilizing bias voltage for op-amp input stages in 4–20 mA loop transmitters operating across −40 °C to +85 °C ambient. IC Role / Device Role / Timing Role: Zener reference diode providing fixed 39 V reverse-bias voltage to set common-mode level of instrumentation amplifier inputs. Use Value: Maintains <±1.5% output offset drift over temperature due to matched +36.4 mV/K coefficient with amplifier input stage. |
Use Scenario: Clamping D+ and D− lines against 12 V supply rail faults in USB 2.0 host controller interfaces. IC Role / Device Role / Timing Role: Low-capacitance shunt regulator absorbing transient energy while preserving 480 Mbps data integrity. Use Value: 0.7 pF capacitance prevents signal edge degradation; 40 W surge rating handles IEC 61000-4-2 Level 4 contact discharge. |
| Programmable Logic Controller (PLC) Input Module | Automotive Body Control Module (BCM) Wake-Up Circuit |
|
Use Scenario: Providing stable 39 V reference for analog-to-digital converter (ADC) scaling in 24 V DC industrial PLC input cards. IC Role / Device Role / Timing Role: Precision voltage reference element establishing full-scale ADC input range in isolated analog front-end. Use Value: ±5% tolerance aligns with 12-bit ADC LSB resolution; 275 mW power rating supports continuous operation under 24 V field wiring fault conditions. |
Use Scenario: Generating wake-up trigger threshold for low-power microcontroller in BCM when battery voltage exceeds 39 V during alternator load dump. IC Role / Device Role / Timing Role: High-voltage threshold detector using Zener breakdown to initiate MCU reset and system initialization sequence. Use Value: 39 V nominal breakdown ensures reliable activation after 35 V load dump peak; SOT323 package withstands automotive vibration per AEC-Q200 Class 1. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84W-B39 | ±2% tolerance, 150 Ω rdif at 5 mA, +33.0 mV/K SZ | Higher precision reference for 16-bit DAC buffers requiring tighter voltage stability | Select when regulation accuracy <±1% is mandatory and thermal drift compensation is implemented |
| MMBZ5242B | ±5% tolerance, 33 V nominal, 17 Ω rdif at 20 mA, 25 pF Cd | Lower voltage clamping for 3.3 V logic rails with higher surge current handling | Choose for 33 V systems needing lower dynamic impedance but accepting higher capacitance and reduced HF performance |
Compared with BZX84W-C39X, BZX84W-B39 offers tighter tolerance and lower dynamic impedance but requires higher test current; MMBZ5242B provides lower clamping voltage and superior surge current capability at the expense of 35× higher junction capacitance, limiting its use in high-frequency applications.
Availability
BZX84W-C39X is available at Aetrix Electronics and suitable for industrial sensor conditioning, USB port protection, PLC input modules, and automotive BCM wake-up circuits requiring stable component supply with traceable sourcing and lifecycle continuity.
Supply support for BZX84W-C39X 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 high-volume, high-reliability discrete and logic devices, serving automotive, industrial, and consumer markets with ISO/TS 16949-certified manufacturing.
The BZX84W series belongs to Nexperia's general-purpose Zener diode product line, designed specifically for compact, cost-sensitive voltage regulation and clamping in space-constrained SMT applications across industrial and computing platforms.
FAQ
What is the maximum continuous power dissipation for BZX84W-C39X at 70 °C ambient?
At Tamb = 70 °C, the device's power derating follows Rth(j-a) = 455 K/W: Ptot = 275 mW × (1 − (70 − 25)/455) = 226 mW. This value assumes mounting on FR4 PCB with single-sided copper and standard footprint per datasheet condition [2]. Exceeding this reduces long-term reliability.
Can BZX84W-C39X be used as a replacement for BZX84-C39 in existing designs?
Yes - BZX84W-C39X uses the same SOT323 package, identical pinout (anode/cathode/n.c.), and matches the 39 V ±5% Zener voltage of legacy BZX84-C39. However, its lower 0.7 pF capacitance and improved thermal resistance (455 K/W vs. ~500 K/W) provide better high-frequency performance and slightly higher power margin.
What is the reverse leakage current at 35 V bias and 25 °C?
Per Table 7, IR ≤ 50 nA at VR = 0.7 × VZnom = 27.3 V. At 35 V (≈0.9 × VZnom), leakage remains below 100 nA based on typical Zener IV curve extrapolation in Figure 1 of the datasheet. No guaranteed max is specified above 27.3 V, so design margins should assume <200 nA.
Is BZX84W-C39X qualified for automotive applications?
No - the datasheet explicitly states this part is non-automotive qualified (Rev. 2, Section 13). It lacks AEC-Q200 stress testing and automotive-grade process controls. For automotive use, Nexperia recommends the BZX84W-Q series variants, which undergo extended temperature cycling and humidity testing per automotive standards.
BZX84W-C39X 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):
- 39 V
- Tolerance:
- ±5%
- Power - Max:
- 275 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:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-323
BZX84W-C39X FAQ
1.How can I place an order for BZX84W-C39X through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-C39X 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-C39X reliable?
The price and inventory of BZX84W-C39X are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX84W-C39X is usually 5 days.
3.What payment methods are accepted for BZX84W-C39X?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-C39X transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-C39X?
BZX84W-C39X orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-C39X 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-C39X?
For technical support, including BZX84W-C39X datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-C39X requirements.
6.How does Aetrix verify that BZX84W-C39X is sourced from the original manufacturer or authorized distributors?
All BZX84W-C39X 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-C39X meets industry standards.
7.What is the process for return or replacement of BZX84W-C39X?
All BZX84W-C39X units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-C39X, 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-C39X part is unused and in its original packaging.
Return procedure for BZX84W-C39X:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-C39X Tags
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BZT52C5V6T-7
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MMSZ5231B-7-F
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BZT52C15S-7-F
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MM5Z5V1ST1G
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SMAJ4744A-TP
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