The 2026 Varistor Technology Seminar, themed “Technology Leadership, Advancing Safety,” was recently held in Nanjing, China.
At the event, Mr. Li Jixiao from Shanghai Boarden Industrial Co., Ltd. delivered a technical presentation titled “Practical Applications and Exploration of CMS SMD Varistors as Alternatives to TVS Diodes.”
The presentation focused on the electrical characteristics, component selection methods, and typical application cases of Boarden’s CMS SMD varistors. Drawing on practical engineering experience, Mr. Li shared insights into overvoltage protection circuit design and explored how CMS technology can provide alternative protection solutions for various electronic applications.
Jammy·LI Presents CMS SMD Varistor Applications as Alternatives to TVS Diodes
As electronic devices become smaller, more power-dense, and increasingly automated in assembly, circuit protection components must balance surge capability, clamping performance, and reliability within limited PCB space. Selecting suitable protection devices for different voltage levels and surge conditions was a key focus of the presentation.
Starting with material properties and application parameters, Li Jixiao compared CMS varistors and TVS diodes. He introduced a four-quadrant selection approach based on operating voltage and surge power, covering low-voltage standard-power, high-voltage standard-power, low-voltage high-surge, and high-voltage high-surge applications.
For practical applications, he shared examples involving PoE security systems, energy storage BMS, high-voltage MOSFET protection, and 800V DC AI computing servers. These cases demonstrated how CMS can replace multiple components with a single device in certain designs, reduce PCB space, and enable the transition from through-hole to surface-mount assembly.
For high-voltage, high-surge applications, he also introduced the development concept and applications of Boarden’s low-clamping-voltage CMSL series. By reducing residual voltage during surge events, CMSL aims to balance surge handling capability with downstream component protection, offering additional options for high-voltage power supplies and third-generation semiconductor circuits.
Jammy·Li Speaking at the Seminar
The presentation also emphasized that replacing TVS diodes with CMS varistors requires a systematic evaluation of the specific circuit. Engineers should consider maximum continuous operating voltage, surge waveforms, clamping voltage, temperature conditions, repeated surge capability, and the voltage tolerance of downstream components. Protection performance must be verified through actual testing. For high-speed signal interfaces or circuits requiring precise voltage clamping, device capacitance and coordinated protection should also be evaluated.
The presentation combined component performance with practical applications, highlighting the advantages, applicable conditions, and verification requirements of CMS alternatives to TVS diodes. It provided practical engineering insights into the use of SMD varistors for circuit protection.
For automotive electronics, energy storage, high-voltage power supplies, and computing infrastructure, the presentation also explored future development directions for low-clamping-voltage products and coordinated system-level protection design.
Group Photo of Participants at the 2026 Varistor Technology Seminar: “Technology Leadership, Advancing Safety”
