Modern power and industrial electronic designs rely on metal oxide varistors (MOVs) to protect circuits from transient voltage surges caused by lightning, switching events, or unstable power conditions. For engineers and sourcing teams evaluating MOV replacement or alternative options, understanding MOV structure, voltage classes, and application suitability is essential.

This article provides a technical overview of JVX Metal Oxide Varistors, focusing on structure, operating characteristics, typical applications, and class-level alternative selection guidance.

Metal Oxide Varistor Structure Overview

A metal oxide varistor is constructed using zinc oxide (ZnO) ceramic grains sandwiched between two metal electrodes, resulting in a highly nonlinear voltage-current characteristic.

• High impedance under normal operating voltage
• Rapid impedance drop when surge voltage exceeds threshold
• Surge energy absorption and voltage clamping

JVX Metal Oxide Varistor Key Characteristics

• Operating temperature: -40°C to +105°C
• Disc diameters: 5D, 7D, 10D, 14D, 20D
• Varistor voltage range: 18V to 1800V
• Compliance: RoHS, REACH

Typical Surge Protection Applications

• Industrial power supplies
• AC-DC converters and SMPS designs
• Home appliance control boards
• Motor drives and inverter systems
• Power protection modules

Class-Level MOV Alternative Selection Guidance

JVX Metal Oxide Varistors are designed to align with common industry MOV voltage and disc-size classes. Comparisons are provided at the class level only and do not constitute direct part-number cross references.

Watch: How Metal Oxide Varistors Protect Circuits

Explore JVX Metal Oxide Varistors

Looking for Jantzen or Mundorf Alternatives? JMX & JLX Audio Capacitors with Fast Lead Time

When engineers search for a Jantzen alternative capacitor or a Mundorf equivalent capacitor, the concern is rarely just brand comparison. What truly matters is whether the audio capacitor replacement can deliver stable electrical performance, predictable sound characteristics, and a supply lead time that supports real project schedules.

JMX and JLX audio capacitors from jb Capacitors are developed to address these evaluation criteria, offering high-end audio performance with clear sourcing advantages. For teams evaluating fast lead time capacitors, the goal is to reduce uncertainty during design-in and RFQ stages.

Product Overview

JMX Series

High-voltage signal path audio capacitor

JLX Series

High-end tweeter & mid-range crossover

JYS Series

SMD MLCC for volume production

JMX – High-Voltage Audio Capacitor for Signal Integrity

The JMX Music Aluminum Foil and Film Metallized Polypropylene Capacitors (Axial) are designed for audio circuits where signal purity and stability are critical. From a design perspective, engineers often consider JMX when evaluating audio capacitor replacements for high-voltage signal paths.

Why JMX is frequently evaluated

• Very low dissipation factor (≤0.0002 @ 1kHz)
• Very low ESR and inductance for clean signal transmission
• Rated voltage up to 630VDC, suitable for high-voltage audio designs
• Commonly used in amplifiers, speakers, and crossover networks

JLX – High-End Audio Capacitor for Tweeter & Mid-Range Applications

The JLX Luxury Aluminum Foil and Film Metallized Polypropylene Capacitors (Axial) are positioned as a high-end solution for modern tweeters and mid-range drivers. In many audio projects, JLX is evaluated as a Mundorf equivalent capacitor or a practical alternative to Jantzen Audio Alumen Z-cap, especially when balancing performance and sourcing considerations.

Why engineers consider JLX

• High precision capacitance tolerance: ±3% @ 1kHz
• Very low dielectric absorption factor
• Very low dissipation factor, very low ESR, very low inductance
• Available in 100V and 200VDC ratings

Third-party listening reviews indicate that JLX delivers a clear high-frequency presentation and balanced mid-range character. For reference, the published test review document is available below.

Why Engineers Inquire About JMX & JLX

When evaluating fast lead time capacitors for audio applications, engineers typically focus on:

• Electrical stability and specification transparency
• Suitability for crossover, tweeter, and signal path designs
• Reliable sourcing with consistent lead time

JMX and JLX are designed to support these requirements, allowing engineers to evaluate alternatives with confidence during design-in and RFQ stages.

RFQ Promotion (Limited Time)

During the promotion period, customers who submit an RFQ via the official website and include at least one JMX or JLX series part number or a clear specification requirement, after jb Capacitors verification, may receive a selected gift.

Notes

• RFQ content must be a real and specific project or design requirement, not a test, blank, or duplicate submission.
• Each company is eligible once during the promotion period.
• Gifts are limited and available while supplies last; jb Capacitors reserves the final right of review and interpretation.

Product Video

As electronic systems move toward higher integration, smaller form factors and increased power density, traditional capacitor limitations become more visible. In modern SMD power designs, capacitor choice directly affects efficiency, thermal behavior and long-term field reliability.

Multilayer solid polymer capacitors such as the JEA and JEB series provide low ESR, stable capacitance and compact SMD packaging, making them well suited for DC–DC converters, processor rails and display power stages where every millimeter of PCB space and every degree of temperature margin matters.

▶ Inside a multilayer solid polymer capacitor structure:

The Role of ESR in Modern Power Circuits

Equivalent Series Resistance (ESR) is one of the key selection parameters for power capacitors. High ESR turns into:

• Additional I²R losses at switching frequency and ripple current
• Higher self-heating and hot spots around dense power stages
• Increased output ripple and poorer transient regulation under load steps

Low ESR solid polymer capacitors help engineers:

• Reduce output ripple on DC–DC converter rails
• Improve transient response for CPUs, ASICs and FPGAs
• Keep case and PCB temperatures under control in compact layouts

Why Solid-State Capacitors Replace Liquid Electrolytics

Compared with liquid electrolytic capacitors, solid polymer designs use a solid conductive polymer layer as the electrolyte. This structure:

• Eliminates evaporation and dry-out failure modes over time
• Maintains more stable capacitance and ESR over temperature
• Provides faster charge–discharge behavior under dynamic load conditions
• Offers better mechanical robustness against vibration and thermal cycling

For procurement teams, this translates into fewer field returns and more predictable product lifetime in applications with 24/7 operation or frequent temperature cycling.

JEA vs. JEB Multilayer Solid Polymer Capacitors

The JEA and JEB series share the same SMD footprint but target slightly different design windows. This allows engineers to keep one PCB pad layout while covering multiple voltage and capacitance requirements.

Selection hints for engineers & buyers

• Use JEA when enclosure height or airflow clearance is tight, and operating voltage is ≤ 16 V.
• Use JEB when rails require up to 25 V or higher bulk capacitance in the same footprint.
• Check ripple current capability at 100 kHz against converter specifications, especially for high-load rails.
• For long-term supply planning, both series share common SMD footprint, simplifying second-source or alternate BOM strategies.

Design Considerations in SMD Power Stages

When integrating JEA / JEB into SMD power designs, engineers typically pay attention to:

• Voltage derating: keep some margin between rated voltage and maximum working voltage for better life and reliability.
• Ripple current vs. temperature rise: confirm that expected ripple current stays within rated limits at the target ambient and airflow conditions.
• Series / parallel combinations: use parallel capacitors to reduce ESR and distribute ripple, or combine with MLCCs to shape impedance across frequency.
• Layout: place caps close to power switches and load pins to minimize parasitic inductance and loop area.

For procurement and project managers, having a single family that can cover multiple rails (5 V, 12 V, 19–24 V, etc.) helps consolidate part numbers and simplify global sourcing.

Typical Applications

Low ESR, RoHS solid-state capacitors such as JEA and JEB are widely deployed in:

• Switching power supplies and DC–DC converters
• System boards and processor power rails
• Display cards, graphics and multimedia modules
• Small chargers, power adapters and USB PD designs
• Intelligent TVs and other consumer electronics

Go Further: Full jb Capacitor Catalogue

For projects that combine polymer capacitors with film, aluminum, tantalum or MLCC families, it is often useful to review all series in one place. The jb full catalogue provides:

• Side-by-side overview of capacitor technologies and series codes
• Voltage and capacitance ranges per family
• Recommended application segments for each series

You can download the complete catalogue for design reviews, internal documentation and sourcing comparison:

👉 jb Capacitors – Full Product Catalogue (PDF)

Choosing the correct pairing of high voltage MLCCs and thick film chip resistors is essential for long-term electrical stability, thermal reliability, and predictable high-voltage performance. In automotive, industrial control, SMPS power stages, and LED drivers, the interaction between MLCC characteristics (DC bias, ESR, ripple, temperature behavior) and resistor performance (power rating, derating, sulphur resistance, and AEC-Q200 compliance) directly affects system lifetime. This guide focuses on jb® JZQ and JZC series and explains how to apply them in high voltage rails, feedback paths, and protection circuits together with high voltage MLCCs.

2.1 JZP vs. JZQ vs. JZC – quick comparison

JZP Series

High power / pulse thick film chip resistor for SMPS, LED drivers, and power stages.

JZQ Series

Automotive AEC-Q200 and anti-sulfur thick film chip resistor for harsh environments.

JZC Series

General-purpose industrial thick film chip resistor for cost-effective designs.

2.2 JZQ – Automotive-grade thick film chip resistor for high voltage MLCC rails

The jb® JZQ series is designed for automotive-grade reliability and is widely used in modules such as TPMS, HVAC systems, wiper modules, navigation equipment, indoor lighting, and central door locking units.

According to the datasheet, JZQ provides:

• AEC-Q200 compliance for automotive qualification.
• Anti-sulfur performance validated through sulphuration testing.
• Stable electrical characteristics under load life, humidity, and thermal cycling.
• A case-size range suitable for common automotive PCB layouts and compact modules.

In practice, JZQ pairs naturally with high voltage MLCCs used in automotive rail filtering, LED lighting control, and body electronics. While MLCCs manage high dv/dt, noise suppression, and decoupling, JZQ provides the stable divider, bleeder, and sense resistor functions needed in designs exposed to vibration, sulphur, and wide ambient temperature ranges.

2.3 JZC – Thick film chip resistor for general power & industrial applications

The jb® JZC series targets high-volume commercial and industrial systems that require consistent performance but do not demand full automotive qualification. It is suitable for:

• SMPS feedback paths and high-voltage divider networks.
• Current limiting and inrush control around MLCC-based filters.
• General-purpose signal conditioning in low-to-medium power rails.

Typical application areas include:

• AC–DC power supplies and LED lighting drivers.
• Industrial control boards and sensor interfaces.
• HVAC controllers, white goods, and consumer electronics.

Compared with JZP and JZQ, the JZC family acts as a versatile, cost-effective “workhorse” series. It supports a broad resistance range and chip sizes, making it ideal for designs governed by internal reliability requirements rather than automotive-specific standards.

3. Pairing high voltage MLCCs with thick film resistors: three practical guidelines

Once the correct resistor series is selected – JZP, JZQ, or JZC – the next step is to ensure the MLCC and resistor behave predictably under worst-case operating conditions. The following three guidelines help prevent common field failures when combining high voltage MLCCs with thick film chip resistors.

3.1 Verify voltage and power margin at maximum temperature

For each design node combining a high voltage MLCC with a thick film resistor, calculate worst-case DC and transient stress:

• Ensure the MLCC's DC and AC voltage ratings include temperature derating and DC bias effects.
• Confirm the resistor's power dissipation and dielectric withstand voltage remain within its derating curve at maximum operating temperature.

A reliable rule of thumb is to stay below the onset of the derating curve rather than approaching absolute maximum ratings. This improves long-term drift performance and reduces the risk of early-life failures.

3.2 Pay attention to layout: creepage, clearance, and hot spots

Even properly rated components can fail due to PCB layout issues when high voltage MLCCs and thick film resistors are placed too close together.

• Maintain correct creepage and clearance around high voltage MLCCs and resistors according to the system voltage and pollution category.
• Avoid placing hot-running resistors next to MLCCs whose capacitance and ESR shift with temperature.
• Use thermal vias or copper pours to spread heat from 1–2 W chip resistors and reduce local hot spots.

Treat the resistor and MLCC as a thermal pair – if one runs hot, the other effectively experiences the same environment.

3.3 Match technologies to environment and qualification needs

Selecting the right combination of MLCC and thick film resistor technology should reflect real operating conditions, contamination risks, and qualification requirements:

• JZQ for automotive, outdoor, or sulphur-rich environments using industrial/automotive-grade MLCCs.
• JZP for compact power or lighting equipment that requires higher power density and robust pulse handling.
• JZC for general consumer and industrial systems with standard derating requirements.

By selecting high voltage MLCCs and thick film resistors as a matched design set, engineers can improve long-term reliability, simplify qualification, and prevent early field failures in high voltage rails and auxiliary circuits.

4. High voltage MLCC + thick film resistor design checklist

• Choose JZQ, JZC, or JZP based on environment, standards, and power level.
• Combine with suitable high voltage MLCCs, accounting for DC bias and derating.
• Validate voltage, power, and temperature margins at the worst-case conditions.
• Review creepage, clearance, and thermal coupling on the PCB layout.
• Document assumptions so future redesigns keep MLCC and resistor behavior aligned.

5. FAQ: High voltage MLCCs and thick film chip resistors

Q1. Why pair high voltage MLCCs with thick film resistors from the same supplier?

Using high voltage MLCCs and thick film resistors as a matched set makes it easier to control derating, temperature behavior, and long-term drift, and simplifies qualification and failure analysis.

Q2. When should I consider an automotive-grade series like JZQ?

Choose JZQ when the design must pass AEC-Q200 or operate in harsh, sulphur-rich, or outdoor environments, especially in automotive and transportation modules.

Q3. Where is JZC a better fit than JZQ?

JZC is a good choice for industrial and consumer power electronics that require consistent performance and broad resistance options but do not need full automotive qualification.

How Low ESR Strengthens Power Integrity

Lower ESR reduces AC losses and temperature rise, improving efficiency and transient behavior.

• Lower output ripple
• Higher converter efficiency
• Cleaner undershoot/overshoot
• Improved reliability under switching stress

ESR_max ≈ ΔV_ripple / I_ripple

Comprehensive Series Portfolio

Impedance profiles and endurance tailored for common SMPS scenarios.

Layout and Reliability Notes

Cross-Reference