Littelfuse, Inc., an industrial technology manufacturing company empowering a sustainable, connected, and safer world, introduced the CPC2501M, a robust, self-actuating, normally closed solid-state relay optimized for chime bypass in video doorbell systems.
Designed to replace discrete relay circuitry, the CPC2501M is the first application-specific integrated circuit (ASIC) in the Littelfuse portfolio for this function. It integrates self-protection, fault timing, and solid-state switching into a single compact 6×6 mm QFN package—simplifying video doorbell integration while enhancing reliability and safety.
“The CPC2501M chime bypass relay enables video doorbell manufacturers to make their product work with existing house installations,” said Hugo Guzman, Product Marketing Manager, Integrated Circuits Division at Littelfuse. “End users can replace the doorbell button with a new video doorbell unit using the existing door chime box—no need for specialized installation or added circuitry.”
Key Features and Benefits
- Integrated self-actuating logic eliminates the need for external microcontrollers or software control
- Built-in fault protection timer (~17 seconds) automatically resets during prolonged button presses or chime failure
- High-performance switching with 60 VP bidirectional voltage and 1.84 ARMS continuous load current
- Peak current capability of 5 A for handling start-up and surge conditions
- Thermally optimized 6×6 mm QFN-16 package conserves PCB space for compact module designs
- Installable behind standard 8–24 VAC doorbell transformers
Problem/Solution
As video doorbell adoption grows, so does the challenge of powering these devices using legacy home wiring and mechanical chimes. The CPC2501M addresses this by creating a power bypass path when the chime is inactive and instantly turning off that path during doorbell operation—ensuring continuous power to the camera unit and full chime functionality without complex retrofitting.
Applications and Markets
While optimized for door chime bypass in video doorbell systems, the CPC2501M is also ideal for:
- Building automation controls
- IoT devices with voltage-controlled actuation
- Security systems requiring compact, solid-state switching
- General-purpose voltage-controlled relay designs
By integrating multiple protection and logic functions, the CPC2501M simplifies design and installation while improving durability and performance in consumer and industrial environments.
Availability
The CPC2501M Voltage Controlled Non-Isolated Solid-State Relays are available in tape and reel format in quantities of 3,000. Sample requests are accepted through authorized Littelfuse distributors worldwide. For a listing of Littelfuse distributors, please visit Littelfuse.com.
