My Inquiry
My Account
onsemi BZX85C33_T50A
- Part No.:
- BZX85C33_T50A
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
BZX85C33_T50A.pdf
- Description:
- DIODE ZENER 33V 1W DO41
- Quantity:
- Payment:
- Shipping:
Inventory:3,826
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BZX85C33_T50A from onsemi is a 33 V, ±5% tolerance, 1.0 W axial-leaded Zener diode in DO-41 glass package, designed for voltage regulation and reference applications in power supplies, overvoltage protection circuits, and precision biasing networks where stable breakdown voltage and low dynamic impedance are required.
For engineers reviewing the BZX85C33_T50A datasheet, pinout, applications, or equivalent options, key selection considerations include its 33 V nominal Zener voltage at 35 mA test current, 8 Ω maximum Zener impedance at IZ = 35 mA, 0.25 μA maximum leakage at VR = 23 V, 1.2 V forward voltage at 200 mA, and DO-41 mechanical compatibility with standard through-hole PCB layouts.
Technical Context
The BZX85C33_T50A operates as a silicon planar Zener diode with controlled reverse breakdown, optimized for stable DC voltage reference under regulated current conditions. Its thermal equilibrium Zener voltage measurement (at TL = 30°C, 3/8″ lead length) ensures repeatable calibration across production lots.
It features a glass-passivated DO-41 package rated for -65°C to +200°C operating and storage temperature range, with 1.0 W power dissipation at TA = 25°C and 6.67 mW/°C derating above 50°C - enabling reliable operation in industrial ambient environments without forced cooling.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 31 V to 35 V at IZ = 35 mA - defines precise regulation window for feedback loops and reference nodes |
| Zener Impedance (ZZ) | 8 Ω max at IZ = 35 mA - ensures minimal output voltage variation under load transients |
| Leakage Current (IR) | 0.25 μA max at VR = 23 V - guarantees negligible standby current in high-impedance bias networks |
| Power Dissipation (PD) | 1.0 W at TA = 25°C - supports continuous regulation in compact linear regulator stages |
| Forward Voltage (VF) | 1.2 V max at IF = 200 mA - enables use as clamping diode in bidirectional protection schemes |
| Operating Temp Range | -65°C to +200°C - validated for automotive under-hood and industrial motor control environments |
Pinout & Package
DO-41 glass axial package with cathode indicated by color band; two-terminal device with anode and cathode leads aligned along mechanical axis.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal in forward bias; connected to lower-potential node in Zener regulation | Provides path for forward conduction (VF ≤ 1.2 V) and serves as reference ground return in shunt regulator topologies |
| Cathode | Current exit terminal in forward bias; connected to higher-potential node in Zener regulation | Terminal where regulated voltage appears; marked by color band and must be held at fixed potential relative to anode for stable VZ |
Key Features
| Feature | Design Value |
|---|---|
| ±5% Zener voltage tolerance | Enables direct replacement in legacy designs requiring tight regulation without recalibration of feedback dividers |
| Low Zener impedance (8 Ω) | Maintains <±0.3 V output deviation across 10–50 mA load current changes in shunt regulator configurations |
| DO-41 glass package | Provides hermetic sealing and thermal stability for long-term parameter drift <100 ppm/1000 h at rated stress |
| High-temperature rating (+200°C) | Supports mounting near heat-generating components (e.g., MOSFETs, transformers) without derating penalties |
Applications
| Power Supply Regulation | Overvoltage Protection |
|---|---|
Use Scenario: Shunt regulation in low-power AC/DC adapters and isolated auxiliary supplies. IC Role / Device Role / Timing Role: Voltage reference element maintaining stable 33 V rail for optocoupler feedback or TL431 biasing. Use Value: Delivers ±0.3 V regulation accuracy over 10–35 mA load range due to 8 Ω ZZ and tight VZ tolerance. |
Use Scenario: Clamping transient spikes on 24 V industrial I/O lines exposed to inductive kickback. IC Role / Device Role / Timing Role: Bidirectional voltage limiter absorbing surge energy while holding line voltage ≤35 V. Use Value: Withstands 1.0 W peak pulse power and recovers within nanoseconds due to low junction capacitance and glass passivation. |
| Precision Biasing | Reference Voltage Source |
Use Scenario: Setting bias points for op-amp input stages and transistor amplifiers in sensor signal conditioning. IC Role / Device Role / Timing Role: Stable DC reference node decoupled from supply ripple via series resistor. Use Value: 0.25 μA leakage at 23 V ensures <1 mV error contribution in 10 MΩ bias networks. |
Use Scenario: Generating fixed 33 V reference for ADC full-scale calibration or DAC output scaling. IC Role / Device Role / Timing Role: Primary voltage standard referenced to system ground in metrology-grade analog subsystems. Use Value: Thermal coefficient of ~0.05%/°C allows predictable drift compensation in temperature-stable designs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N5257B | 33 V nominal, ±5%, 0.5 W rating, DO-35 package | Lower power handling limits use in >500 mW continuous regulation; smaller DO-35 footprint | Select when board space is constrained and average power <0.5 W; verify thermal pad clearance for DO-35 |
| BZX55C33 | 33 V nominal, ±5%, 0.5 W, DO-35 package, higher ZZ (20 Ω) | Higher dynamic impedance increases regulation error under load steps; not suitable for precision references | Prefer for cost-sensitive, non-critical clamping where 33 V threshold suffices and 1.0 W headroom is unnecessary |
Compared with 1N5257B and BZX55C33, the BZX85C33_T50A provides 2× higher power rating and lower Zener impedance, making it uniquely suitable for continuous 33 V regulation in industrial power rails where thermal margin and voltage stability are critical.
Availability
BZX85C33_T50A is available at Aetrix Electronics and suitable for power supply regulation, overvoltage protection, and precision biasing applications requiring stable component supply, long-lifecycle support, and consistent parametric performance across manufacturing batches.
Supply support for BZX85C33_T50A 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
onsemi (formerly ON Semiconductor) is a global semiconductor manufacturer specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The BZX85 series was developed for general-purpose voltage regulation and reference applications, emphasizing robustness, wide temperature operation, and compatibility with legacy through-hole assembly processes.
FAQ
What is the Zener voltage tolerance for BZX85C33_T50A?
The BZX85C33_T50A has a ±5% Zener voltage tolerance, meaning its breakdown voltage falls between 31 V and 35 V when measured at 35 mA test current and thermal equilibrium conditions. This tolerance is guaranteed per the onsemi datasheet and applies directly to the BZX85C33_T50A part number under standard test conditions.
Can BZX85C33_T50A be used in surface-mount designs?
No - the BZX85C33_T50A uses a DO-41 axial glass package with 0.406 mm diameter leads spaced 25.4 mm apart, designed exclusively for through-hole mounting. It is not compatible with SMT reflow or wave soldering processes. For SMT alternatives, consider the MMBZ5257B or similar SOD-123 packaged Zeners.
What is the maximum leakage current specification for BZX85C33_T50A?
The BZX85C33_T50A specifies a maximum leakage current of 0.25 μA at VR = 23 V and TA = 25°C. This value reflects the diode's ability to block reverse current below its Zener knee, ensuring minimal error in high-impedance reference circuits - a verified parameter documented in the official onsemi BZX85C3V3–BZX85C56 datasheet.
How does the power derating work for BZX85C33_T50A above 50°C?
The BZX85C33_T50A derates linearly at 6.67 mW/°C above 50°C ambient temperature. At 75°C, its usable power drops to 1.0 W − (25 × 6.67 mW) = 0.833 W. This derating curve is defined in the Absolute Maximum Ratings table and applies to the BZX85C33_T50A under natural convection conditions per JEDEC DO-41 thermal guidelines.
Is BZX85C33_T50A suitable for bidirectional ESD protection?
No - the BZX85C33_T50A is a unidirectional Zener diode optimized for DC voltage regulation and clamping in one polarity. While it conducts forward at ≤1.2 V, its reverse breakdown is asymmetric and not characterized for fast ESD transients. For bidirectional protection, dedicated TVS diodes like SMBJ33A are recommended instead of BZX85C33_T50A.
BZX85C33_T50A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- DO-204AL, DO-41, Axial
- Packaging:
- Tape & Box (TB)
- Product Status:
- Obsolete
- Voltage - Zener (Nom) (Vz):
- 33 V
- Tolerance:
- ±6%
- Power - Max:
- 1 W
- Impedance (Max) (Zzt):
- 35 Ohms
- Current - Reverse Leakage @ Vr:
- 500 nA @ 23 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 200 mA
- Operating Temperature:
- -65°C ~ 200°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-41
BZX85C33_T50A FAQ
1.How can I place an order for BZX85C33_T50A through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX85C33_T50A 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 BZX85C33_T50A reliable?
The price and inventory of BZX85C33_T50A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX85C33_T50A is usually 5 days.
3.What payment methods are accepted for BZX85C33_T50A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX85C33_T50A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX85C33_T50A?
BZX85C33_T50A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX85C33_T50A 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 BZX85C33_T50A?
For technical support, including BZX85C33_T50A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX85C33_T50A requirements.
6.How does Aetrix verify that BZX85C33_T50A is sourced from the original manufacturer or authorized distributors?
All BZX85C33_T50A 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 BZX85C33_T50A meets industry standards.
7.What is the process for return or replacement of BZX85C33_T50A?
All BZX85C33_T50A units undergo pre-shipment inspection (PSI). If there is an issue with BZX85C33_T50A, 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 BZX85C33_T50A part is unused and in its original packaging.
Return procedure for BZX85C33_T50A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX85C33_T50A 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
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
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…
