On Semi NCL30051 60W LED驱动解决方案

The NCL30105 is a peak current controlled fixed off time buck controller designed for LED driver applications. It is optimized to operate in deep continuous conduction mode ELiminating the need for output electrolytic capacitors. Featuring an adjustable off time generator, the controller can drive a MOSFET up to a switching frequency of 500 kHz. A dedicated dimming pin enables the use of a pulsewidth modulated logic signal to dim the LED directly. The soft-start pin creates a startup sequence that slowly ramps up the peak current and enables the adjustment of the peak current set point for analog dimming control. The device features robust protection features to detect switch overcurrent faults and to detect maximum on time events.

NCL30051主要特性:

• Constant Off Time Current−Mode Control Operation

• Adjustable Off Time (0.5 [1]s to 10 [1]s)

• Internal Leading Edge Blanking

• Source 250 mA / Sink 500 mA Peak Drive Capability

• ±3.2% Current Sense Accuracy at 25℃• Internal Startup Delay

• 3.3 V Logic Level Dimming Input

• This is a Pb−Free Device

NCL30051安全特性:

• Thermal Shutdown

• Maximum On Time Protection

• Overcurrent Protection

NCL30051典型应用:

• LED Backlight Drivers for LCD Panels

• LED Light Bars

• LED Street Lighting

• LED Bulbs

图1.NCL30051方框图

图2.NCL30051典型应用框图

图3.NCL30051典型应用电路图

图4. 评估板NCL30105GEVB外形图:输入高达80V,输出350mA
图5. 评估板NCL30105GEVB电路图(1)

图6. 评估板NCL30105GEVB电路图(2)
评估板NCL30105GEVB材料清单:



图7. 评估板NCL30105GEVB元件布局图:顶层