Rosmont, Illinois, March 17, 2026 - Littelfuse Corporation (NASDAQ: LFUS) is a diversified industrial technology manufacturing company dedicated to providing power for a sustainable, connected, and safer world. Today, the company announces the launch of CPC1343G OptoMOS® Solid State Relay, a compact normally open (1-A type) OptoMOS relay, designed for high-reliability switching in demanding industrial, medical, and instrumentation applications. 

CPC1343G is based on Littelfuse OptoMOS technology, combining a continuous load current of 900 mA, a 60 V breakdown voltage, and enhanced 5000 VRMS input-to-output isolation. It is designed to meet strict safety and compliance requirements in a space-saving 4-pin package. The fast switching performance (4 ms on-state and 1 ms off-state) enables precise control in modern electronic systems, while the low maximum LED drive current of 3 mA ensures compatibility with TTL and CMOS logic without increasing the interface circuit. 

CPC1343G is specially designed for harsh operating environments and supports an extended environmental temperature range of -40 °C to +105 °C. This exceeds the +85 °C limitation commonly found in many competing SSRs. Its solid-state structure eliminates mechanical wear, providing quiet, maintenance-free operation and long-term reliability, which electromechanical relays often cannot achieve. 

The design has been optimized in terms of security, efficiency and space constraints. 

The maximum on-resistance of CPC1343G is 0.8 Ω. It can minimize power dissipation and improve thermal performance under higher load currents. This device offers through-hole DIP-4 and surface mount two configurations, simplifying PCB layout and enabling flexible manufacturing options across industrial and medical platforms. 

"With the launch of CPC1343G, we will offer our customers a high-performance solid-state relay that combines enhanced isolation, fast switching and extended temperature capabilities," said Dr. Hugo Guzman, the product marketing manager of Littelfuse. "This solution can address the key reliability and safety challenges in space-constrained designs, helping engineers reduce maintenance, enhance system robustness and accelerate product launch speed." 

Packaging and Ordering Options 

The CPC1343G series offers a variety of packaging options, which have been optimized to meet different assembly and size requirements: 

Target market and application 

CPC1343G is highly suitable for applications that require high isolation, fast response, and reliable operation under high temperatures, including: 

· Industrial control systems and automation; 

· Medical equipment that requires isolation from patients; 

· Instruments, data acquisition and multiplexing; 

· Automatic Test Equipment (ATE); 

Public utilities and intelligent metering systems. 

CPC1343G integrates high current handling capability, enhanced isolation, and compact packaging, expanding Littelfuse's OptoMOS product lineup and providing designers with compliant switching solutions suitable for next-generation electronic systems. 

Common Questions and Answers: Learn more about these high-current OptoMOS solid-state relays. 

What are the differences between CPC1343G and traditional electromechanical relays? Unlike electromechanical relays, CPC1343G has no moving parts. It can operate silently and without maintenance at high temperatures, with faster switching speed, higher isolation performance and greater reliability. 

2. How is CPC1343G different from similar solid-state relays? It can offer a higher continuous load current (900 mA compared to ~550 mA), a lower on-resistance (0.8 Ω compared to ~2.5 Ω), and a maximum operating temperature of +105 °C, thereby providing better thermal performance and energy efficiency. 

3. Is CPC1343G compatible with the low-power control logic? Yes. The maximum LED driving current required for this device is only 3 mA, making it fully compatible with TTL and CMOS logic and eliminating the need for an additional driver. 

4. Which applications can benefit the most from the enhanced isolation of CPC1343G? The 5000 VRMS enhanced isolation can support strict safety and regulatory requirements. Medical devices, industrial control, instrumentation and measurement applications can all benefit from it. 

5. What packaging options are available? CPC1343G offers through-hole DIP-4 and surface-mount packages, including reel options suitable for automated mass production. 

Supply situation 

Depending on the selected packaging, each tube of these solid-state relays contains 100 units or each roll contains 1,000 units. Sample requests can be submitted through authorized Littelfuse distributors worldwide. 

Regarding Littelfuse 

Littelfuse (NASDAQ: LFUS) is a diversified industrial technology manufacturing company dedicated to providing power for a sustainable, interconnected, and safer world. With operations spanning over 20 countries and approximately 16,000 global employees, we collaborate with customers to design and deliver innovative, reliable solutions. Serving over 100,000 end customers, our products are applied daily in various industrial, transportation, and electronic end markets around the world. Littelfuse has 7 sales offices, 7 R&D centers, and 8 manufacturing plants in China, providing local services with global resources for our customers.