My Inquiry
My Account
Nexperia USA Inc. BZX84W-B68-QX
- Part No.:
- BZX84W-B68-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-B68-QX.pdf
- Description:
- DIODE ZENER 68V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:6,580
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BZX84W-B68-QX from Nexperia is a ±2 % tolerance Zener voltage regulator diode with a nominal breakdown voltage of 68 V, rated for 275 mW total power dissipation at 25 °C, and qualified to AEC-Q101 for automotive use in compact SOT323 (SC-70) surface-mount packaging. It delivers stable reference voltage in low-power regulation circuits where space-constrained PCB layouts demand high reliability.
For engineers reviewing the BZX84W-B68-QX datasheet, BZX84W-B68-QX pinout, BZX84W-B68-QX application, or BZX84W-B68-QX equivalent, key selection criteria include its 68 V Zener voltage tolerance, 275 mW power rating on FR4 PCB, 455 K/W junction-to-ambient thermal resistance, and AEC-Q101 qualification status for under-hood automotive electronics.
Technical Context
This Zener diode operates in reverse-bias breakdown mode to maintain a stable 68 V reference across load variations, with differential resistance of 475 Ω at IZ = 2 mA and temperature coefficient of +71.7 mV/K at the same current. Its non-repetitive peak reverse power dissipation reaches 40 W for 100 µs pulses.
The device features a three-terminal SOT323 package with anode (Pin 1), not-connected (Pin 2), and cathode (Pin 3); Pin 2 is internally unconnected and must remain floating. Junction temperature is rated up to 150 °C, supporting operation in extended ambient ranges from −55 °C to +150 °C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 66.6 V to 69.4 V at IZ = 2 mA - defines precise regulation window for 68 V nominal reference |
| Power Dissipation (Ptot) | 275 mW on FR4 PCB - sets maximum continuous DC power handling in standard layout |
| Differential Resistance (rdif) | 475 Ω at IZ = 2 mA - determines output impedance and regulation sensitivity to current changes |
| Temperature Coefficient (SZ) | +71.7 mV/K at IZ = 2 mA - quantifies voltage drift per degree Celsius rise in junction temperature |
| Reverse Current (IR) | 50 nA at VR = 47.6 V - specifies leakage level below breakdown, critical for low-power standby circuits |
| Junction-to-Ambient Rth | 455 K/W - defines thermal bottleneck limiting sustained power in still-air conditions |
| Non-repetitive Peak Power | 40 W for 100 µs pulse - enables transient overvoltage clamping without damage |
Pinout & Package
SOT323 (SC-70) leadless surface-mount plastic package with 3 terminals; dimensions: 2.2 mm × 1.35 mm × 0.95 mm (L × W × H), 0.65 mm pitch.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Forward-current entry point; connected to lower-potential side in Zener regulation configuration |
| 2 | Not Connected (n.c.) | Internally unconnected terminal; must be left floating-no PCB trace or solder joint required |
| 3 | Cathode (K) | Reverse-bias voltage reference node; connected to higher-potential side and load return path |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive-grade reliability including temperature cycling, humidity, and mechanical stress testing |
| ±2 % Zener voltage tolerance | Enables tighter regulation accuracy than ±5 % variants, reducing need for post-production trimming |
| Low capacitance (0.25 pF) | Minimizes signal distortion in high-frequency applications such as RF biasing and fast transient suppression |
| High surge capability (40 W, 100 µs) | Provides robust ESD and load-dump protection without external TVS stacking |
| Extended temperature range | Operates continuously from −55 °C to +150 °C ambient, suitable for engine control and transmission modules |
Applications
| Automotive Engine Control Unit (ECU) Reference | Industrial Sensor Signal Conditioning |
|---|---|
|
Use Scenario: Providing stable 68 V reference for analog front-end circuitry in diesel common-rail fuel injection controllers. IC Role / Device Role / Timing Role: Zener voltage reference diode establishing precision bias point for op-amp comparators monitoring rail pressure feedback. Use Value: Maintains regulation accuracy within ±2 % across −40 °C to +125 °C ambient, eliminating calibration drift during cold-start and hot-soak cycles. |
Use Scenario: Stabilizing excitation voltage for piezoresistive pressure transducers in hydraulic valve position feedback systems. IC Role / Device Role / Timing Role: Precision shunt reference supplying constant current source for bridge sensor excitation. Use Value: Delivers <50 nA leakage at 47.6 V reverse bias, ensuring microamp-level sensor bias stability in battery-powered remote monitoring nodes. |
| Telecom Line Card Overvoltage Protection | Medical Infusion Pump Power Monitoring |
|
Use Scenario: Clamping induced surges on 48 V DC distribution lines in base station line cards exposed to lightning-induced transients. IC Role / Device Role / Timing Role: Fast-response Zener clamp absorbing 40 W non-repetitive pulses without degradation. Use Value: Withstands 100 µs surges at full rated power, enabling single-device protection without series resistors or cascaded TVS stages. |
Use Scenario: Monitoring 24 V DC input integrity in Class II medical infusion pumps requiring fault-tolerant power supervision. IC Role / Device Role / Timing Role: High-stability Zener element in comparator-based undervoltage lockout (UVLO) circuit. Use Value: +71.7 mV/K temperature coefficient enables predictable trip-point shift across operating temperature, simplifying safety-critical threshold design. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84W-C68-Q | ±5 % tolerance (64.0 V–72.0 V) vs. ±2 % (66.6 V–69.4 V); identical package, power, and thermal specs | Acceptable where system-level calibration compensates for wider voltage spread | Select when cost sensitivity outweighs need for tight regulation; same footprint and assembly process |
| MMSZ4695T1G | 68 V nominal, ±5 %, 500 mW Ptot, SOD-123 package; higher power but larger footprint and no AEC-Q101 rating | Used in industrial power supplies where automotive qualification is unnecessary and board space permits larger package | Choose only if 500 mW dissipation is required and AEC-Q101 compliance is not mandated |
Compared with BZX84W-C68-Q, the BZX84W-B68-QX offers tighter voltage control at identical thermal and mechanical compatibility; versus MMSZ4695T1G, it trades higher power for automotive qualification and 30 % smaller PCB area in SOT323.
Availability
BZX84W-B68-QX is available at Aetrix Electronics and suitable for automotive ECU designs, industrial sensor interfaces, telecom line card protection, and medical power supervision requiring stable component supply with guaranteed long-term continuity.
Supply support for BZX84W-B68-QX 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, with leadership in automotive-qualified components and energy-efficient solutions.
The BZX84W-Q series belongs to Nexperia's AEC-Q101-qualified Zener diode product line, engineered specifically for precision voltage reference and transient suppression in space-constrained automotive and industrial electronics.
FAQ
What is the maximum continuous reverse current the BZX84W-B68-QX can sustain at 25 °C?
The device does not specify a maximum continuous reverse current; instead, its safe operating limit is defined by total power dissipation. At 25 °C ambient on a standard FR4 PCB, it supports up to 275 mW, corresponding to approximately 4.04 mA at 68 V (P = V × I). Exceeding this current risks thermal runaway due to the positive temperature coefficient above ~5 V.
Can Pin 2 (n.c.) be grounded or tied to a voltage rail?
No-Pin 2 is internally not connected and must remain electrically floating. Connecting it to ground, VCC, or any other node violates the device's internal construction and may cause unpredictable leakage, parametric shift, or premature failure. PCB layout must omit any copper trace or solder mask opening at Pin 2.
How does the +71.7 mV/K temperature coefficient affect regulation accuracy over temperature?
At IZ = 2 mA, the Zener voltage increases by +71.7 mV per Kelvin rise in junction temperature. Over a 100 K range (e.g., 25 °C to 125 °C), this yields a +7.17 V shift-approximately +10.5 % of nominal 68 V. System designers must account for this drift in precision references, either via compensation circuitry or by restricting operating temperature range.
Is the BZX84W-B68-QX suitable for use in high-frequency AC signal clipping?
Yes-the device exhibits only 0.25 pF junction capacitance at 1 MHz and 0 V bias, enabling clean clipping up to ~1 GHz in small-signal applications. However, its 475 Ω dynamic resistance limits large-signal fidelity; for RF clipping above 100 MHz, verify waveform distortion using measured S-parameters or SPICE models from Nexperia's official simulation library.
BZX84W-B68-QX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX84W-Q
- Package/Case:
- SC-70, SOT-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 68 V
- Tolerance:
- ±2.06%
- Power - Max:
- 275 mW
- Impedance (Max) (Zzt):
- 240 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 47.6 V
- Voltage - Forward (Vf) (Max) @ If:
- 900 mV @ 10 mA
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-323
BZX84W-B68-QX FAQ
1.How can I place an order for BZX84W-B68-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-B68-QX 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-B68-QX reliable?
The price and inventory of BZX84W-B68-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX84W-B68-QX is usually 5 days.
3.What payment methods are accepted for BZX84W-B68-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-B68-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-B68-QX?
BZX84W-B68-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-B68-QX 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-B68-QX?
For technical support, including BZX84W-B68-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-B68-QX requirements.
6.How does Aetrix verify that BZX84W-B68-QX is sourced from the original manufacturer or authorized distributors?
All BZX84W-B68-QX 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-B68-QX meets industry standards.
7.What is the process for return or replacement of BZX84W-B68-QX?
All BZX84W-B68-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-B68-QX, 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-B68-QX part is unused and in its original packaging.
Return procedure for BZX84W-B68-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-B68-QX 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…
