Fairchild Introduces HB LED Reference Design Without Secondary Side Circuitry

Fairchild Semiconductor has introduced an illumination reference design, the RD226, for AC input LEDs without the use of secondary side control circuitry and optocouplers for LED lighting applications.

The RD226 is a universal input 12W LED lighting solution that reduces the size of high-brightness (HB) LED lamps and saves bill of materials (BOM) costs. The design uses an isolated primary side control off-line AC-DC converter with a flyback topology with a universal input voltage range of 85VRMS to 265VRMS and a line frequency of 50Hz to 60Hz.

The RD226 also offers selectable constant current outputs of 350mA and 700mA, both with a maximum output voltage of 17V. This reference design uses Fast Semiconductor's FAN102 as the primary side control Pwm Controller to reduce overall cost and reduce product size.

High-brightness (HB) LED applications with AC power inputs require a circuit to convert the AC input voltage to a constant current, and in some applications, the complexity of the design is added because the load must be isolated from the power supply input. The traditional approach requires the use of a flyback converter with a constant current output.

In most cases, the primary-side control circuit uses an op amp with a reference circuit, or uses only one dedicated control IC to regulate the current, and sends a control message to the PWM Controller that is fed back to the primary side via the optocoupler. Innovative solutions from Fast Semiconductor allow designers to eliminate the need for secondary side control circuits and optocouplers in AC input LED lighting system designs.

Fast Semiconductor offers a broad portfolio of reference designs that save board space, simplify design, and ensure system reliability and faster time to market. These production-ready designs can play an important role in helping OEMs reduce design time and bring their applications to market faster.


Lead Acid batteries (LA), usually called Acidic batteries.

Use Lead and Lead Sulphate electrodes and Sulphuric acid electrolyte.

Construction classification:

The batteries divided also into two major groups based on its construction:-

• Vented batteries, also called open batteries with removable caps.

• Sealed batteries with valve regulator, usually used for lead acid batteries (Valve Regulated Lead Acid -VRLA).

The VRLA batteries classified to AGM or Gel groups based on the electrolyte media if it is Glass mate or Silica Gel.



ABG Battery/Gel Battery

Abg Battery,Gel Battery,Gel Cell Battery,Gel Car Battery

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