LED 1-5W driver solution

On Semi's NCP3065 is a 1.5A constant current switching regulator with an input voltage range of 3.0V to 40V, a feedback voltage of 235mV, an adjustable operating frequency up to 250kHz, and cycle-by-cycle current limiting. It is mainly used in automotive lighting, high-power LED drivers, constant current sources, and low-voltage LED lighting. This article introduces the main features, block diagram, typical buck application circuit, buck demo board application circuit and bill of materials, boost demo board application circuit and bill of materials, as well as the 1-5W MR16 LED driver GreenPoint solution block diagram, application circuit and bill of materials.

NCP3065, NCV3065: Up to 1.5 A Constant Current Switching Regulator for LEDs The NCP3065 is a monolithic switching regulator designed to deliver constant current for powering high brightness LEDs. The device has a very low feedback voltage of 235 mV (nominal) which is used to regulate the average current of the LED string. In addition, the NCP3065 has a wide input voltage up to 40 V to allow it to operate from 12 Vac or 12 Vdc supplies commonly used for lighting applications as well as unregulated supplies such as Lead Acid batteries. The device 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. The NCP3065 switching regulator can be configured in Step−Down (Buck) and Step−Up (boost) topologies with a minimum number of external components.

NCP3065主要特性:

• Integrated 1.5 A Switch

• Input Voltage Range from 3.0 V to 40 V

• Low Feedback Voltage of 235 mV

• Cycle−by−Cycle Current Limit

• No Control Loop Compensation Required

• Frequency of Operation Adjustable up to 250 kHz

• Operation with All Ceramic Output Capacitors or No Output Capacitance

• Analog and Digital PWM Dimming Capability

• Internal Thermal Shutdown with Hysteresis

• Automotive Version Available

NCP3065应用:

• Automotive and Marine Lighting

• High Power LED Driver

• Constant Current Source

• Low Voltage LED Lighting

(Landscape, Path, Solar, MR16 Replacement)

图1.NCP3065方框图

图2.NCP3065典型降压应用电路

图3.NCP3065降压演示板应用电路

材料清单(BOM):

Figure 4. NCP3065 boost demo board application circuit

材料清单(BOM):



图5.NCP3065降压演示板应用电路(2)

材料清单(BOM):


1-5W MR16 LED驱动GreenPoin解决方案

This reference document describes a built and tested, GreenPoint® solution for a 1 to 5WLED driver for MR16 LED replacement. The circuit is proposed for driving HB--LED (high--brightness LED) in a variety of lighting applications but is configured in size and features for an MR16 LED replacement. Configurations like this are found in 12 Vac / 12 Vdc track lighting applications, automotive applications, and low voltage AC landscaping applications as well as task lighting such as under--cabinet lights and desk lamps that might be powered from standard off--the—shelf Vac wall adapters.

The circuit is based around the ON Semiconductor NCP3065 operating at ~150 kHz in a non—isolated configuration. A key consideration in this design was achieving flat current regulation across input line variation and output voltage variation with a 12 Vac input. It also features an auto--detect circuit in combination with the NCP3065 which allows input from a 12 Vdc or 12 Vac supply and still maintain targeted output current regulation.

图6.1-5W MR16 LED驱动方框图

图7.1-5W MR16 LED驱动器外形图

图8.1-5W MR16 LED驱动器电路图

材料清单: