Products, Materials + Tools | Jul 26, 2010

ON Semiconductor’s New Constant Current Switching Regulators Efficiently Drive High Brightness LEDs

ON Semiconductor (Nasdaq: ONNN), a global leader in power semiconductor solutions, today introduced the NCP3065 switching regulator designed to efficiently drive high brightness LEDs (HB-LED) typically used in, low voltage lighting, landscape path and solar lighting, Halogen bulb replacements, and automotive and marine lighting. Several reference designs are available that drive the industry's latest HB-LEDs in various buck, boost and SEPIC applications.

The NCP3065 is a 1.5 amp (A) monolithic switching regulator that features a very low feedback voltage of 235 millivolts (mV). The feedback voltage is used to regulate the average current through the LED string in a constant current regulator configuration. The low feedback voltage also allows the use of a smaller and more cost competitive sense resistor. The power dissipation in the sense resistor is reduced by 80 percent compared to competitive devices which utilize a standard 1.25 volts (V) feedback voltage. This can result in up to 2 percent savings on the overall system efficiency. The internal reference voltage is trimmed to 2 percent to provide very accurate current regulation even with wide variations in input voltage, LED forward voltage and inductor tolerance.

The device has a wide input voltage range from 3 V up to 40 V to allow operation from 12 Vac and 12 Vdc supplies commonly used for lighting applications and unregulated power supplies such as Lead Acid batteries. The devices can be configured in a controller topology with the addition of an external transistor to support higher LED currents beyond the 1.5 A rated switch current of the internal transistor. In a boost configuration, the external switch also enables the capability of higher output voltages.

Additional Features:
• Thermal Shutdown Protection
• Cycle-by-Cycle Current Limit
• 4 mm x 4mm DFN Package
• No External Compensation Components Needed

“The NCP3065 offers our customers a versatile and easy-to-implement regulator for High-Bright LED (HB-LED) applications”” said Tim Kaske, ON Semiconductor product line marketing manager for the Power Regulation Product Group. “We had a customer recently looking to utilize a HB-LED in a handheld lighting application. It needed to fit into the existing area and thermal solution of an incandescent bulb. The NCP3065 in the small 4 x 4 mm DFN package was the only solution available that could meet the efficiency, thermal, size and voltage requirements. We are already seeing that with the flexibility and performance of the NCP3065, it is becoming the standard for dc-dc conversion in HB-LED applications at our customers.”

The NCP3065 is also available in automotive grade as the NCV3065. The NCP3065 and NCV3065 are offered in a 4 mm x 4 mm DFN-8 package and priced at $0.32 per unit in 10,000 unit quantities. The devices are also offered in an SOIC-8 and a PDIP-8 package priced at $0.30 per unit in 10,000 unit quantities.

For additional information, visit http://www.onsemi.com/tech or contact Tim Kaske at tim.kaske@onsemi.com .

About ON Semiconductor:
With its global logistics network and strong portfolio of power semiconductor devices, ON Semiconductor (Nasdaq: ONNN) is a preferred supplier of power solutions to engineers, purchasing professionals, distributors and contract manufacturers in the power supply, computer, consumer, portable/wireless, automotive and industrial markets. For more information, please visit ON Semiconductor’s website at http://www.onsemi.com .

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