My Inquiry
My Account
Vishay General Semiconductor - Diodes Division BZX55C20-TR
- Part No.:
- BZX55C20-TR
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- Single Zener Diodes
- Package:
- DO-204AH, DO-35, Axial
- Datasheet:
-
BZX55C20-TR.pdf
- Description:
- DIODE ZENER 20V 500MW DO204AH
- Quantity:
- Payment:
- Shipping:
Inventory:7,417
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BZX55C20-TR from Vishay Semiconductors is a 20 V ±5% tolerance, 500 mW silicon Zener diode in DO-35 package, designed for precision voltage regulation and reference applications at 5 mA test current with 15 Ω dynamic impedance and +0.03%/K temperature coefficient at 25 °C.
For engineers reviewing the BZX55C20-TR datasheet, BZX55C20-TR pinout, BZX55C20-TR application, or BZX55C20-TR equivalent, this device serves as a stable, low-noise, single-element voltage clamp in power supply feedback loops, overvoltage protection circuits, and analog reference subsystems requiring tight Zener voltage control and predictable thermal drift.
Technical Context
The BZX55C20-TR operates in reverse breakdown mode with sharp knee characteristics and low reverse leakage (< 0.1 μA at VR = 15 V), enabling accurate clamping across industrial temperature ranges (–65 °C to +175 °C). Its junction-to-ambient thermal resistance is 300 K/W at 4 mm lead length, supporting reliable operation under continuous DC or pulsed conditions up to 500 mW.
It exhibits a positive temperature coefficient of +0.03%/K at 25 °C and +0.11%/K at 150 °C, ensuring predictable voltage drift in ambient-varying environments. The device uses standard DO-35 glass-passivated construction with UL 94 V-0 molding compound and MSL level 1 moisture sensitivity rating.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 18.8 V min., 20 V nominal, 21.2 V max. at IZT = 5 mA - defines precise clamping threshold for regulation circuits |
| Power Dissipation (Ptot) | 500 mW - sets maximum continuous DC or average pulsed power handling capability |
| Dynamic Resistance (ZZ) | < 55 Ω at IZT = 5 mA - ensures minimal output voltage variation under load current changes |
| Reverse Leakage Current (IR) | < 0.1 μA at VR = 15 V - guarantees low standby power loss and high impedance in off-state |
| Temperature Coefficient (TKVZ) | +0.03%/K at 25 °C - enables predictable, linear voltage drift for temperature-compensated designs |
| Junction Temperature Range | –65 °C to +175 °C - supports operation in harsh automotive, industrial, and outdoor environments |
| Package | DO-35 (DO-204AH) - industry-standard axial glass package with cathode band marking and 125 mg mass |
Pinout & Package
DO-35 (DO-204AH) axial-leaded glass package with cathode identified by a painted band; leads are tinned and solderable per J-STD-020 peak temperature ≤ 260 °C.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / low-side connection in Zener configuration | Connected to lower potential node when used in reverse-biased regulation; carries forward current up to 200 mA (VF ≤ 1.5 V) |
| Cathode | Zener breakdown terminal / high-side connection in regulation circuit | Connected to higher potential node; defines regulated output voltage referenced to anode; marked with visible band on glass body |
Key Features
| Feature | Design Value |
|---|---|
| Very sharp reverse characteristic | Enables clean, well-defined breakdown onset at 20 V, reducing regulation uncertainty in low-current sensing |
| Low reverse leakage current | < 0.1 μA at 15 V allows use in ultra-low-power bias networks without compromising accuracy |
| High stability and low noise | Supports precision analog references where long-term drift and broadband noise must be minimized |
| UL 94 V-0 flammability rating | Meets safety requirements for enclosed industrial and consumer power supplies |
| MSL Level 1 moisture sensitivity | Permits unlimited floor life and standard reflow without baking, simplifying SMT assembly logistics |
Applications
| Power Supply Feedback Loop | Overvoltage Protection Circuit |
|---|---|
Use Scenario: Regulating output voltage in discrete linear regulator or SMPS feedback path using optocoupler-coupled error amplifier. IC Role / Device Role / Timing Role: Zener reference element providing stable 20 V threshold for error signal generation. Use Value: Tight 20 V ±5% tolerance and low dynamic impedance ensure < ±1% output voltage deviation across line/load/temperature variations. |
Use Scenario: Clamping transient surges on 15 V rail in industrial PLC I/O module to prevent downstream IC damage. IC Role / Device Role / Timing Role: Standalone shunt protector absorbing energy above 20 V during ESD or inductive kick events. Use Value: Sub-0.1 μA leakage preserves rail integrity during normal operation; 500 mW rating handles short-duration transients without degradation. |
| Analog Voltage Reference | Signal Level Translation |
Use Scenario: Generating stable bias point for op-amp input stage in sensor signal conditioning circuit operating from unregulated 24 V supply. IC Role / Device Role / Timing Role: Precision DC reference source delivering fixed 20 V to establish common-mode voltage. Use Value: +0.03%/K tempco minimizes offset drift over –40 °C to +85 °C ambient, improving measurement repeatability. |
Use Scenario: Shifting logic-level signals between 3.3 V microcontroller and 20 V actuator interface in home automation hub. IC Role / Device Role / Timing Role: Passive level translator using Zener clamp to limit high-side swing to 20 V while preserving low-side logic compatibility. Use Value: Sharp knee and low capacitance (< 50 pF typical) maintain signal edge integrity up to 1 MHz without distortion or delay. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4744A | 20 V nominal, 1 W power rating, DO-41 package, 22 Ω ZZ, +0.05%/K tempco | Higher power handling but larger footprint and less stable tempco; requires PCB layout revision | Select when >500 mW surge absorption is required and DO-41 mounting is acceptable |
| BZX85C20 | 20 V nominal, 1.3 W, DO-41, 20 Ω ZZ, +0.05%/K, higher leakage (≤1 μA) | Greater thermal margin but looser leakage spec compromises low-power reference use | Prefer for ruggedized industrial power rails where leakage is non-critical and heat sinking is available |
Compared with BZX55C20-TR, the 1N4744A offers higher power but less thermal stability and larger package, while the BZX85C20 trades tighter leakage control for greater dissipation-making BZX55C20-TR optimal for space-constrained, low-drift, low-power regulation where DO-35 fit and <0.1 μA leakage are essential.
Availability
BZX55C20-TR is available at Aetrix Electronics and suitable for voltage stabilization, overvoltage protection, analog reference generation, and signal level translation requiring stable component supply and consistent parametric performance across production lots.
Supply support for BZX55C20-TR 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
Vishay Semiconductors is a global leader in discrete semiconductors, specializing in high-reliability diodes, MOSFETs, optoelectronics, and passive components for industrial, automotive, and computing markets.
The BZX55-Series is part of Vishay's small-signal Zener portfolio engineered for precision voltage reference and stabilization in cost-sensitive, space-constrained applications demanding low noise, sharp breakdown, and long-term stability.
FAQ
What is the Zener voltage tolerance of BZX55C20-TR?
The BZX55C20-TR has a Zener voltage range of 18.8 V (minimum) to 21.2 V (maximum) at 5 mA test current, corresponding to a ±5% tolerance around the nominal 20 V rating. This tolerance is guaranteed per Vishay's Rev. 2.0 datasheet (Document Number: 85604) and applies under standard test conditions at 25 °C ambient temperature.
Does BZX55C20-TR support surface-mount assembly?
No, BZX55C20-TR uses the DO-35 (DO-204AH) axial-leaded glass package and is intended for through-hole mounting. It is not a surface-mount device; however, its MSL Level 1 rating and 260 °C peak solder temperature compliance simplify wave soldering and hand-soldering processes without preconditioning.
What is the maximum reverse leakage current for BZX55C20-TR?
The maximum reverse leakage current for BZX55C20-TR is < 0.1 μA at VR = 15 V, as specified in the Vishay BZX55-Series datasheet (Rev. 2.0, page 2). This ultra-low leakage supports high-impedance bias networks and precision reference applications where standby current must be minimized.
Can BZX55C20-TR be used in place of BZX55B20?
No-BZX55C20-TR and BZX55B20 differ in voltage tolerance: BZX55C20-TR is ±5% (18.8–21.2 V), while BZX55B20 is ±2% (19.6–20.4 V). Substituting them requires verification of system-level voltage margin; BZX55C20-TR provides wider tolerance for cost-sensitive applications where tighter regulation is not required.
What is the thermal resistance of BZX55C20-TR?
The junction-to-ambient thermal resistance (RthJA) of BZX55C20-TR is 300 K/W under standard test conditions (lead length l = 4 mm, TL constant), per the Absolute Maximum Ratings table in the Vishay datasheet. This value assumes free-air convection and defines worst-case temperature rise at full 500 mW dissipation.
BZX55C20-TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Series:
- BZX55
- Package/Case:
- DO-204AH, DO-35, Axial
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 20 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- 55 Ohms
- Current - Reverse Leakage @ Vr:
- 100 nA @ 15 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.5 V @ 200 mA
- Operating Temperature:
- -65°C ~ 175°C
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-204AH (DO-35)
BZX55C20-TR FAQ
1.How can I place an order for BZX55C20-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX55C20-TR 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 BZX55C20-TR reliable?
The price and inventory of BZX55C20-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX55C20-TR is usually 5 days.
3.What payment methods are accepted for BZX55C20-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX55C20-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX55C20-TR?
BZX55C20-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX55C20-TR 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 BZX55C20-TR?
For technical support, including BZX55C20-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX55C20-TR requirements.
6.How does Aetrix verify that BZX55C20-TR is sourced from the original manufacturer or authorized distributors?
All BZX55C20-TR 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 BZX55C20-TR meets industry standards.
7.What is the process for return or replacement of BZX55C20-TR?
All BZX55C20-TR units undergo pre-shipment inspection (PSI). If there is an issue with BZX55C20-TR, 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 BZX55C20-TR part is unused and in its original packaging.
Return procedure for BZX55C20-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX55C20-TR 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
Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…
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…
