Littelfuse | CPC2501M Solid State Relay IC with Integrated Ring Bypass Function for Video Doorbells

Compact self-protecting design simplifies installation for IoT security systems, home and building automation

Industrial Control Network
2025/7/21 10:29:39

CPC2501M 固态继电器

Rosemont, Illinois, July 15, 2025 — Littelfuse, Inc. (NASDAQ: LFUS), an industrial technology manufacturing company dedicated to powering a sustainable, connected, and safer world, today announced the launch of the CPC2501M. This is a powerful, self-driven, normally closed solid-state relay specifically optimized for bell bypass in video doorbell systems.

Designed to replace discrete relay circuits, the CPC2501M is the first Application-Specific Integrated Circuit (ASIC) in Littelfuse's portfolio dedicated to this function. It integrates self-protection, fault timing, and solid-state switching capabilities within a compact 6mm x 6mm QFN package, simplifying the integration process for video doorbells while significantly enhancing system reliability and safety.

"The CPC2501M bell bypass relay enables video doorbell manufacturers to ensure their products are compatible with existing residential wiring systems," said Hugo Guzman, Product Marketing Manager for the Integrated Circuit Business Unit at Littelfuse. "End-users can replace their doorbell button with a new video doorbell unit using the existing doorbell chime box, eliminating the need for professional installation or additional wiring."

Key Features and Benefits

• Integrated Self-Driven Logic: Operates without requiring an external microcontroller or software control.

• Built-in Fault Protection Timer (~17 seconds): Automatically resets in cases of a stuck button or chime failure.

• High-Performance Switching: Supports 60 VP bidirectional voltage and 1.84 ARMS continuous load current.

• Peak Current Capability (5 A): Handles inrush and surge currents.

• Thermally Optimized 6mm x 6mm QFN-16 Package: Saves PCB space for compact module designs.

• Installation Compatibility: Can be installed behind standard 8-24 VAC doorbell transformers.

Problem/Solution

As video doorbells grow in popularity, the challenge of powering these devices using traditional home wiring and mechanical chimes becomes more significant. The CPC2501M addresses this by creating a power bypass path when the chime is inactive and immediately closing this path when the chime operates. This ensures continuous power for the camera unit while fully preserving the chime function, all without complex retrofitting.

Applications and Markets

While optimized for bell bypass in video doorbell systems, the CPC2501M is also well-suited for:

• Building Automation Controls

• IoT Devices with Voltage-Controlled Drivers

• Security Systems requiring compact solid-state switching

• General-Purpose Voltage-Controlled Relay Designs

By integrating multiple protection and logic functions, the CPC2501M significantly enhances device durability and operational performance in both consumer and industrial applications, while simultaneously simplifying design and installation processes.

Availability

The CPC2501M Voltage-Controlled Non-Isolated Solid State Relay is supplied in tape-and-reel packaging, with a minimum order quantity of 3,000 units. Sample requests are accepted through Littelfuse's authorized global distributors. For a list of authorized Littelfuse distributors, visit Littelfuse.com.

More Information

For more details, please visit the CPC2501M Voltage-Controlled Non-Isolated Solid State Relay product page. For technical inquiries, please contact:

• Hugo Guzman, Product Marketing Manager, Integrated Circuit Business Unit (SBU), at hguzmanjimenez@Littelfuse.com

• Anthony Konopka, Product Marketing Engineer, Integrated Circuit Business Unit (SBU), at AKonopka@Littelfuse.com

About Littelfuse

Littelfuse (NASDAQ: LFUS) is a diversified industrial technology manufacturing company empowering a sustainable, connected, and safer world. With operations in over 20 countries and approximately 16,000 global employees, we collaborate with customers to design and deliver innovative, reliable solutions. Serving more than 100,000 end customers, our products are used every day in a wide range of industrial, transportation, and electronics end markets worldwide. In China, Littelfuse supports customers with the "Global Resources, Local Support" model, operating 7 sales offices, 7 R&D centers, and 8 manufacturing facilities. For more information, visit Littelfuse.com.