We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is a Curve Tracer?

By Meg Higa
Updated May 21, 2024
Our promise to you
All The Science is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At All The Science, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

A curve tracer is a piece of high voltage testing equipment, used primarily in a manufacturing facility’s quality control laboratory. It subjects an electronic component to either a continuous, or stepped, range of power inputs to determine the component’s performance, efficiency or tolerances. The resulting output data from the component is typically plotted on a graph as a curve, which gives the instrument its name.

The principles and operation of a curve tracer are quite straightforward. A testing target, such as a diode, transistor or switched thyristor, is inserted into the machine. This step may be delicate because modern electronic components are microscopic, solid-state semiconductor circuits. The machine is capable of introducing precise power, a mix of voltage and amps, to the circuit’s input terminal. The circuit’s output terminal is ported through an oscilloscope to measure the change in the power as displayed in waves of voltage and amplitude.

A targeted component is called the device under test (DUT). The earliest curve tracers tested the electrical circuits built within sterile vacuum tubes and displayed their output on an oscilloscope for the operator to analyze and record. Modern tracers still display this, but are also equipped with computers to automate the testing process and compile the results.

The basic measurement of a curve tracer is input voltage against output current, or V-I. The X-axis of the graph is the equipment’s power; the Y-axis is the DUT’s output signatures. Among the conclusions which can be readily drawn from the curve is voltage leakage, a measurement of the circuit’s efficiency. For diodes for alternating current (DIAC) thresholds, the X-Y curve will clearly verify the precise voltage that triggers the diode’s on-versus-off state. The curve tracer can also reverse +/- polarity to identify defective circuits and localize sources of interference.

Components with resistor gates, and components requiring a third input current, can be similarly tested with all modern testing equipment. They can also spatially display the curve in an X-Y-Z grid, but diagnostically, they are manually intensive, requiring stepped control of voltage input. Testable electronic components include triodes with alternating current switches (TRIAC) and thyristors with gated switches. Most equipment can also test two circuits simultaneously, useful for evaluating performance by comparison.

Different models of the testing equipment vary according to the maximum voltage they are able to generate and channel to their very small terminals. Some units are rated at up to 2,000 volts. The high voltage and the resulting heat present a safety hazard for operators of curve tracers. The incorporation of computer interfaces to the testing equipment has automated processes and allowed operators of some models to safely control them remotely.

All The Science is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.

All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.