Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Diodes > Zener > Single Zener Diodes

Nexperia USA Inc. BZX79-C20,133

Name: BZX79-C20,133
Brand: Nexperia USA Inc.
SKU: BZX79-C20,133
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: BZX79-C20,133

Manufacturer:: Nexperia USA Inc.

Category:: Single Zener Diodes

Package:: DO-204AH, DO-35, Axial

Datasheet:: BZX79-C20,133.pdf

Description:: DIODE ZENER 20V 400MW ALF2

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:9,824

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

BZX79-C20,133 from Nexperia is a ±5% tolerance Zener voltage regulator diode with nominal 20 V regulation at 5 mA test current, 60 Ω typical differential resistance, and −12.3 mV/K temperature coefficient. Packaged in hermetically sealed SOD27 (DO-35) glass axial package, it delivers stable low-power voltage reference for analog signal conditioning and power supply feedback loops.

For engineers reviewing the BZX79-C20,133 datasheet, BZX79-C20,133 pinout, BZX79-C20,133 application, or BZX79-C20,133 equivalent, this page provides verified electrical parameters, thermal limits, junction-to-ambient thermal resistance, reverse leakage behavior at VR = 14 V, and validated alternative Zeners for precision reference and stabilization use cases.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain a stable DC voltage across its terminals under varying load or input conditions. Its 20 V nominal Zener voltage is specified at I_Ztest = 5 mA, with differential resistance of ≤225 Ω (max) ensuring minimal voltage shift under current variation.

The device exhibits a negative temperature coefficient of −12.3 mV/K (typical), meaning its Zener voltage decreases linearly with rising junction temperature - a critical factor when used in temperature-sensitive references or compensated bias networks.

Key Specifications

Parameter	Value and Actual Design Meaning
Zener Voltage V_Z	19.6 V to 20.4 V at I_Z = 5 mA - defines regulation window for stable reference generation
Differential Resistance r_dif	60 Ω (typ), ≤225 Ω (max) at I_Z = 5 mA - determines output impedance and load regulation sensitivity
Temperature Coefficient S_Z	−12.3 mV/K (typ) - quantifies voltage drift per degree Celsius rise in junction temperature
Reverse Leakage I_R	≤200 nA at V_R = 14 V - ensures minimal parasitic current in high-impedance reference nodes
Total Power Dissipation P_tot	500 mW at T_amb = 50 °C - sets maximum continuous power handling on standard PCB mounting
Non-repetitive Peak Power P_ZSM	40 W for t_p = 100 μs - supports transient overvoltage clamping in surge protection circuits
Junction-to-Ambient R_{th j-a}	380 K/W - defines thermal rise per watt under standard lead-mount conditions

Pinout & Package

Hermetically sealed SOD27 (DO-35) axial glass package with cathode indicated by a band on one end. Leads are tinned copper-clad steel, suitable for wave or hand soldering. Package dimensions: D = 1.85 mm max, L = 25.4 mm min, b = 0.56 mm max.

Pin/Terminal	Circuit Role	Design Meaning
Anode	Forward conduction terminal / low-voltage side in Zener operation	Connected to lower potential node; carries forward current up to 250 mA or reverse leakage during regulation
Cathode	Breakdown terminal / regulated voltage output node	Marked with band; referenced to system ground or feedback point; holds stable 20 V under controlled reverse bias

Key Features

Feature	Design Value
±5% Zener voltage tolerance	Enables cost-effective voltage referencing where tight regulation is not required, e.g., non-critical biasing or coarse supply monitoring
Hermetic glass SOD27 package	Provides long-term stability and moisture resistance without encapsulation degradation, critical for industrial and automotive environments
500 mW total power dissipation	Supports continuous operation in compact PCB layouts without heatsinking under ambient ≤50 °C
Low 200 nA reverse leakage at 14 V	Minimizes error in high-impedance voltage divider or op-amp reference inputs, preserving accuracy in precision analog stages
−12.3 mV/K tempco	Allows predictable compensation in temperature-stable references when paired with positive-tempco components

Applications

Power Supply Feedback

Analog Signal Conditioning

Use Scenario: Used in TL431-based adjustable SMPS feedback networks to set output voltage via resistor divider.

IC Role / Device Role / Timing Role: Zener reference element providing stable 20 V threshold for optocoupler biasing and error amplifier reference.

Use Value: Enables accurate 24 V output regulation with <±1% tolerance across line/load variations due to low dynamic impedance and stable tempco.

Use Scenario: Embedded in op-amp non-inverting gain stage to clamp common-mode input range.

IC Role / Device Role / Timing Role: Voltage limiter protecting ADC front-end from overvoltage transients during sensor excitation.

Use Value: Limits input swing to 20 V ±0.4 V, preventing saturation and enabling full-scale 16-bit resolution without clipping artifacts.

Industrial Sensor Biasing

Microcontroller Reset Circuit

Use Scenario: Supplies regulated bias to 4–20 mA current loop transmitter ICs in process control modules.

IC Role / Device Role / Timing Role: Low-drift Zener source establishing precise 20 V rail for DAC and current-sense amplifier biasing.

Use Value: Maintains <0.5% output drift over −40 °C to +85 °C due to hermetic packaging and known tempco, ensuring loop accuracy.

Use Scenario: Configured as manual reset supervisor with RC delay network on ARM Cortex-M0+ microcontrollers.

IC Role / Device Role / Timing Role: Threshold detector triggering POR (power-on reset) when V_CC crosses 20 V during brown-out recovery.

Use Value: Provides deterministic reset assertion at 20.0 V ±0.4 V, eliminating false resets caused by supply ripple or noise.

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener voltage regulation applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
1N4746A	20 V ±5%, 1 W rating, DO-41 package, 20 Ω r_dif, −12.5 mV/K tempco	Higher power handling enables higher-current reference designs; larger DO-41 footprint requires PCB layout change	Select when >500 mW continuous dissipation or improved thermal margin is needed
BZX84-C20	20 V ±5%, SOT-23 surface-mount, 300 mW rating, 100 Ω r_dif, −12.0 mV/K tempco	Compact size suits space-constrained PCBs but reduces thermal mass and surge capability	Select for automated assembly and high-density layouts where 40 W peak surge is not required

Compared with BZX79-C20,133, the 1N4746A offers higher power and lower impedance but requires through-hole rework, while the BZX84-C20 enables miniaturization at the cost of reduced surge robustness and higher dynamic impedance - choice depends on thermal, layout, and reliability priorities.

Availability

BZX79-C20,133 is available at Aetrix Electronics and suitable for industrial sensor biasing, microcontroller reset circuits, analog signal conditioning, and power supply feedback requiring stable component supply and long-term parametric consistency.

Supply support for BZX79-C20,133 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 leader in discrete, logic, and PowerMOS semiconductors, serving automotive, industrial, computing, consumer, and wearable markets with high-volume, high-reliability components.

The BZX79 series belongs to Nexperia's legacy Zener diode portfolio designed specifically for low-power voltage regulation and reference applications in cost-sensitive, thermally stable environments.

FAQ

What is the maximum continuous reverse current this diode can handle at 20 V?

The BZX79-C20,133 does not specify a maximum continuous reverse current at 20 V; instead, its safe operating area is defined by power dissipation limits. At 20 V, the maximum continuous reverse current is 25 mA (500 mW ÷ 20 V), assuming ambient temperature ≤50 °C and standard PCB mounting per datasheet note 2.

Can this Zener be used in parallel for higher current capability?

No - Zener diodes like the BZX79-C20,133 should not be paralleled due to mismatched breakdown voltages and thermal runaway risk. Even small V_Z variations cause current hogging; use a single higher-power Zener (e.g., 1N4746A) or active regulation instead.

Is the cathode band polarity consistent across all SOD27-packaged Nexperia Zeners?

Yes - the cathode band on all SOD27 (DO-35) packaged Nexperia Zener diodes, including BZX79-C20,133, marks the cathode terminal. This aligns with JEDEC DO-35 standard marking convention and must be oriented toward the higher-potential node in reverse-bias regulation circuits.

How does the −12.3 mV/K temperature coefficient affect long-term reference stability?

A −12.3 mV/K coefficient means the Zener voltage drops ~0.246 V over a 20 °C rise (e.g., from 25 °C to 45 °C). In a 20 V reference, that's ~1.23% drift - acceptable for non-precision applications but requires compensation (e.g., with a positive-tempco resistor) in metrology-grade designs.

BZX79-C20,133 Specifications

Product attributes: Attribute value

Manufacturer:: Nexperia USA Inc.

Series:: -

Package/Case:: DO-204AH, DO-35, Axial

Packaging:: Cut Tape (CT)

Product Status:: Active

Voltage - Zener (Nom) (Vz):: 20 V

Tolerance:: ±5%

Power - Max:: 400 mW

Impedance (Max) (Zzt):: 55 Ohms

Current - Reverse Leakage @ Vr:: 50 nA @ 14 V

Voltage - Forward (Vf) (Max) @ If:: 900 mV @ 10 mA

Operating Temperature:: -65°C ~ 200°C

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: ALF2

BZX79-C20,133 FAQ

1.How can I place an order for BZX79-C20,133 through Aetrix?

Please submit a Request for Quotation (RFQ) for BZX79-C20,133 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 BZX79-C20,133 reliable?

The price and inventory of BZX79-C20,133 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX79-C20,133 is usually 5 days.

3.What payment methods are accepted for BZX79-C20,133?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX79-C20,133 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BZX79-C20,133?

BZX79-C20,133 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BZX79-C20,133 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 BZX79-C20,133?

For technical support, including BZX79-C20,133 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX79-C20,133 requirements.

6.How does Aetrix verify that BZX79-C20,133 is sourced from the original manufacturer or authorized distributors?

All BZX79-C20,133 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 BZX79-C20,133 meets industry standards.

7.What is the process for return or replacement of BZX79-C20,133?

All BZX79-C20,133 units undergo pre-shipment inspection (PSI). If there is an issue with BZX79-C20,133, 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 BZX79-C20,133 part is unused and in its original packaging.

Return procedure for BZX79-C20,133:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-09-03 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

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.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

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…

2026-09-01 74HC595 Pinout, Timing, Output Current, and Applications

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…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

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…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

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 …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

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…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

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…

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

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…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

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…

2026-08-14 Jumper Cables: How to Use, Connect and Choose Them Safely

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…