My Inquiry
My Account
Nexperia USA Inc. BZX84W-B33-QF
- Part No.:
- BZX84W-B33-QF
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-B33-QF.pdf
- Description:
- DIODE ZENER 33V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:3,797
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BZX84W-B33-QF from Nexperia is a ±2% tolerance Zener voltage regulator diode in SOT323 (SC-70) package, rated for 33 V nominal Zener voltage at 5 mA, 275 mW total power dissipation, and qualified to AEC-Q101 for automotive use. It provides stable voltage reference in low-power biasing, overvoltage protection, and signal clamping circuits.
For engineers reviewing the BZX84W-B33-QF datasheet, BZX84W-B33-QF pinout, BZX84W-B33-QF application, or BZX84W-B33-QF equivalent, this page delivers verified Zener parameters, automotive-grade reliability context, thermal resistance data, and validated alternative parts for voltage reference design.
Technical Context
This device operates as a reverse-biased Zener diode with a nominal 33 V breakdown voltage at IZ = 5 mA, exhibiting 325 Ω typical differential resistance and +29.7 mV/K temperature coefficient. Its non-repetitive peak reverse power dissipation reaches 40 W for 100 µs pulses.
Designed for surface-mount use on FR4 PCBs with single-sided copper, it achieves 455 K/W junction-to-ambient thermal resistance under standard footprint conditions and maintains <100 nA reverse leakage at VR = 0.7 × VZnom.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 32.3 V to 33.7 V at IZ = 5 mA - defines precise regulation window for reference stability |
| Tolerance | ±2% (B-series) - enables tighter voltage margin control vs. ±5% C-series counterparts |
| Power Dissipation (Ptot) | 275 mW at Tamb = 25 °C - sets maximum continuous DC power handling on standard FR4 layout |
| Differential Resistance (rdif) | 325 Ω max at IZ = 5 mA - determines output impedance and load regulation sensitivity |
| Reverse Leakage (IR) | 50 nA max at VR = 23.1 V - ensures minimal quiescent current in high-impedance bias networks |
| Thermal Resistance (Rth(j-a)) | 455 K/W - quantifies junction temperature rise per watt on standard PCB mounting |
| Forward Voltage (VF) | 0.9 V max at IF = 10 mA - defines anode-cathode drop during forward conduction |
Pinout & Package
Package: SOT323 (SC-70), leadless surface-mount plastic package with 3 terminals, 1.3 mm × 1.8 mm footprint, 0.65 mm pitch.
| 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 terminal; must remain floating-no PCB trace or solder mask required |
| 3 | Cathode (K) | Reverse-bias connection point; tied to higher-potential node for Zener operation |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive underhood and infotainment applications requiring extended temperature and reliability compliance |
| 275 mW power rating | Enables direct replacement of legacy 250 mW Zeners without thermal derating on standard FR4 layouts |
| 325 Ω differential resistance | Supports stable regulation under varying load currents up to 10 mA with ≤3.3% voltage deviation |
| 455 K/W thermal resistance | Allows junction temperature rise of ≤125 °C at full 275 mW dissipation in ambient 25 °C environments |
| 100 nA max reverse leakage | Minimizes error in precision reference dividers and high-impedance sensor biasing networks |
Applications
| Automotive ECU Power Monitoring | Industrial Sensor Signal Clamping |
|---|---|
Use Scenario: Detecting battery overvoltage (>32 V) in 24 V vehicle ECUs to trigger shutdown logic. IC Role / Device Role / Timing Role: Zener-based comparator reference input, providing fixed 33 V threshold against which supply rail is compared. Use Value: ±2% tolerance ensures trip point remains within 32.3–33.7 V across temperature, meeting ISO 16750-2 transient immunity requirements. |
Use Scenario: Protecting analog front-end inputs of 3.3 V ADCs from transient spikes in factory automation sensors. IC Role / Device Role / Timing Role: Reverse-biased clamping diode limiting input voltage to 33 V while passing normal 0–5 V signals. Use Value: 40 W non-repetitive surge capability absorbs 100 µs transients without degradation, preserving ADC integrity. |
| Low-Power IoT Reference Bias | High-Frequency RF Detector Bias |
Use Scenario: Generating stable 33 V bias for ultra-low-power LDO feedback networks in battery-operated gateways. IC Role / Device Role / Timing Role: Precision shunt reference supplying regulated current to resistive divider network. Use Value: 50 nA leakage at 23.1 V ensures <1 µA total quiescent current in 100 kΩ bias chain, extending battery life. |
Use Scenario: Setting DC operating point for GaAs FET detectors in 2.4 GHz ISM-band receivers. IC Role / Device Role / Timing Role: DC bias source establishing optimal gate voltage for detector linearity and noise floor. Use Value: 0.9 V forward drop allows clean forward conduction during RF envelope peaks without distorting detector response. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84W-C33-Q | ±5% tolerance (31.0–35.0 V range) vs. ±2% (32.3–33.7 V); identical package, power, and thermal specs | Acceptable where wider regulation margin is permitted, e.g., non-critical power supervision | Select when cost sensitivity outweighs tight voltage accuracy needs |
| MMSZ5257ET1G | 33 V ±5%, SOD-123 package, 500 mW rating, higher thermal resistance (625 K/W), no AEC-Q101 qualification | Suitable for commercial-grade power supplies but not automotive due to qualification gap and larger footprint | Choose only for non-automotive designs requiring higher power or existing SOD-123 layout compatibility |
Compared with BZX84W-B33-QF, the C33-Q variant trades voltage precision for cost in identical automotive-qualified packaging, while MMSZ5257ET1G offers higher power but lacks AEC-Q101 validation and increases board area-making BZX84W-B33-QF optimal for space-constrained, safety-critical 33 V references.
Availability
BZX84W-B33-QF is available at Aetrix Electronics and suitable for automotive ECU monitoring, industrial sensor clamping, and low-power IoT reference biasing requiring stable component supply across production lifecycles.
Supply support for BZX84W-B33-QF 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 and logic devices.
This part belongs to the BZX84W-Q series of AEC-Q101-qualified Zener diodes engineered specifically for automotive voltage regulation and protection in harsh-environment electronic control units.
FAQ
What is the maximum continuous reverse current the BZX84W-B33-QF can sustain at 33 V?
The device is rated for 200 mA maximum forward current, but as a Zener diode, its continuous reverse current is limited by power dissipation. At 33 V, the absolute maximum DC reverse current is 8.3 mA (275 mW ÷ 33 V), assuming Tamb = 25 °C and standard PCB mounting. Derating is required above 25 °C ambient.
Does the n.c. pin (pin 2) require any PCB layout treatment?
No. Pin 2 is internally not connected and must remain electrically floating. No solder mask opening, copper trace, or thermal pad is needed. Standard SOT323 reflow footprints (e.g., 0.55 mm pad width × 0.6 mm length) accommodate this terminal without modification.
How does the +29.7 mV/K temperature coefficient affect regulation accuracy over −40 °C to +125 °C?
Over that range, the Zener voltage shifts approximately +3.0 V (29.7 mV/K × 100 K), resulting in a 33 V device operating between ~33.0 V at −40 °C and ~36.0 V at +125 °C. This drift is inherent to mid-voltage Zeners and must be accounted for in wide-temperature reference designs.
Can BZX84W-B33-QF replace older BZX84-C33 in existing designs?
Yes, with caveats: both share SOT23-3 pinout and 33 V rating, but BZX84W-B33-QF uses SOT323 (smaller), has ±2% tolerance (vs. ±5%), and is AEC-Q101 qualified. Layout adaptation is required for the smaller SC-70 footprint, and thermal performance differs due to package geometry.
BZX84W-B33-QF 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):
- 33 V
- Tolerance:
- ±2.12%
- Power - Max:
- 275 mW
- Impedance (Max) (Zzt):
- 80 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 23.1 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-B33-QF FAQ
1.How can I place an order for BZX84W-B33-QF through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-B33-QF 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-B33-QF reliable?
The price and inventory of BZX84W-B33-QF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX84W-B33-QF is usually 5 days.
3.What payment methods are accepted for BZX84W-B33-QF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-B33-QF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-B33-QF?
BZX84W-B33-QF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-B33-QF 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-B33-QF?
For technical support, including BZX84W-B33-QF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-B33-QF requirements.
6.How does Aetrix verify that BZX84W-B33-QF is sourced from the original manufacturer or authorized distributors?
All BZX84W-B33-QF 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-B33-QF meets industry standards.
7.What is the process for return or replacement of BZX84W-B33-QF?
All BZX84W-B33-QF units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-B33-QF, 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-B33-QF part is unused and in its original packaging.
Return procedure for BZX84W-B33-QF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-B33-QF 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…
