650V buck switches reduce design time and complexity

Combining a PWM controller and a discrete MOSFET in a single package, the FSL306 and FSL336 provide higher reliability through rich protection features, such as a Safe Auto Restart Mode. Setting a fixed restart time of 650ms for safe auto-restart mode of all protection features, this reduces the stress on the system during a long-term fault, thereby improving system reliability. The internal high-voltage startup switch and the Burst-Mode operation with very low operating current reduce the power loss in Standby Mode. As the result, it is possible to reach power loss of 120 mW without external bias and 25 mW with external bias when input voltage is 230V ac.

A high-voltage regulator enables operation without an auxiliary bias winding, while a built-in error amplifier provides direct feedback without a shunt regulator, reducing overall bill of material cost and saving board space. With an adjustable current limit pin that helps simplify designs and reduce design time, the FSL306 offers power scalability of 0.5-3W.

JaeKuk Ryu, Marketing Manager, Home Appliance and Industrial Power Product Line, Fairchild, comments: "Our customers are searching for higher power for their designs because of the added smart functionality and relay functions in their systems. To address this, we developed a higher power buck switch that has the lowest RDS(ON) available. The FSL336 features an industry-leading RDS(ON) of 4Ω, which in turn enables our customers to provide the most energy efficient solutions to their end-users."

Priced at $0.83 (USD) and $0.85 (USD), each respectively, in 1,000 unit quantities, the FSL306 and FSL336 are available now. With lead times of 8-12 weeks ARO for large orders, samples available upon request.