原标题：NXP SSL1750 75W LED调光驱动方案

　　nxp 公司的SSL1750 是开关电源(SMPS)控制器,适合用于25W到250W LED驱动应用. SSL1750包括功率因素修正(PFC)控制器和反激控制器.通用输入电压70 V 到 276 V (AC),具有多种保护特性和片内起动电流源.主要用在室内LED照明和户外LED照明如街灯,区域照明如停车场以及隧道照明.本文介绍SSL1750主要特性, 方框图, 典型配置电路以及120V(AC) 75W TRIAC可调光LED驱动器电路图,材料清单和230V (AC) 75W TRIAC可调光LED驱动器电路图和材料清单.

　　The SSL1750 is a Switched Mode Power Supply (SMPS) controller IC, suitable for driving LED applications from 25 W up to 250 W. For LED power requirements below 25 W the SSL152x family and SSL1623PH are the best choice.

　　The SSL1750 combines a controller for Power Factor Correction (PFC) and a flyback controller. Its high level of integration allows the design of a cost-effective LED power supply with a very low number of external components.

　　The special built-in green functions provide high efficiency at all power levels. This applies to quasi-resonant operation at high power levels, quasi-resonant operation with valley skipping, as well as to reduced frequency operation at lower power levels. At low power levels, the PFC switches over to burst mode control to maintain high efficiency. In burst mode, soft-start and soft-stop functions are added to eliminate audible noise.

　　During low power conditions, the flyback controller switches to frequency reduction mode and limits the peak current to 25 % of its maximum value. This will ensure high efficiency at low power while minimizing audible noise from the transformer.

　　The proprietary high voltage BCD800 process makes direct start-up possible from the rectified universal mains voltage in an effective and green way. A second low voltage Silicon On Insulator (SOI) IC is used for accurate, high speed protection functions and control.

　　The SSL1750 enables highly efficient and reliable LED drivers with power requirements of up to 250 W to be designed easily and with the minimum number of external components.

　　SSL1750主要特性:

　　Distinctive features

　　Integrated PFC and flyback controller

　　Universal mains supply operation (70 V to 276 V (AC))

　　High level of integration resulting in a very low external component count and a cost

　　effective design

　　Green features

　　On-chip start-up current source

　　PFC green features

　　Valley/zero voltage switching for minimum switching losses (patented)

　　Frequency limitation to reduce switching losses

　　Burst mode operation if a low load is detected at the flyback output (patented)

　　Flyback green features

　　Valley switching for minimum switching losses (patented)

　　Frequency reduction with fixed minimum peak current at low power operation to

　　maintain high efficiency at low output power levels

　　Protection features

　　Safe restart mode for system fault conditions

　　Continuous mode protection by means of demagnetization detection for both

　　converters (patented)

　　Undervoltage protection (foldback during overload)

　　Accurate OverVoltage Protection (OVP) for both converters (adjustable for flyback

　　converter)

　　Open control loop protection for both converters

　　IC overtemperature protection

　　Low and adjustable OverCurrent Protection (OCP) trip level for both converters

　　Soft-(re)start for both converters

　　Soft-stop PFC to minimize audible noise

　　Mains undervoltage protection / brownout protection

　　General purpose input for latched protection, e.g. to be used for system OverTemperature Protection (OTP)

　　SSL1750主要应用:

　　• Indoor LED applications (> 25 W):

　　– Spot lights

　　– Down lights

　　– Other SSL consumer/industrial fixtures

　　• Outdoor LED applications (> 25 W):

　　– Street lighting

　　Area lighting (e.g. car parking)

　　Tunnel lighting

　　图1.SSL1750方框图

　　图2.SSL1750应用电路

　　图3.SSL1750典型配置电路

　　UM10394:火线120V 75W TRIAC可调光LED驱动器

　　This SSL1750 board is a 75 W, 1000 mA current regulated, LED driver that is dimmable with standard mains triac dimmers. The board is using the NXP SSL1750 switched mode power supply with integrated power factor correction (PFC) and a flyback controller. The circuitry for communication between both controllers is integrated and needs no adjustment. The PFC output power is on-time controlled for simplicity. It is not necessary to sense the phase of the mains voltage. The flyback output-power is current-mode controlled for good suppression of input-voltage ripple.

　　The board is very efficient, higher than 85 %, has a high power factor, above 0.95 over the whole voltage input range and the THD falls within the limits for class-C equipment.Making this board ideal for dimmable high power LED lighting systems.

　　The board has been optimized for triac-based dimmers. As different triac dimmers have different specifications the dimming performance of the reference board might vary based on the used dimmer. Transistor dimmers and other non-triac dimmers are not tested with this board.

　　图4. 75W TRIAC可调光LED驱动器板外形图

　　图5.SSL1750T简化功能应用框图

　　图6. TRIAC相位检测器

　　图7.120V(AC)/60Hz 75W TRIAC调光LED驱动器电路图

　　120V(AC)/60Hz 75W TRIAC调光LED驱动器材料清单(BOM):

　　UM10321: 230V(AC)/50Hz 75W TRIAC调光LED驱动器电路图

　　75 W SSL1750 triac dimmable 230 V mains LED driver

　　图8.230V(AC)/50Hz 75W TRIAC调光LED驱动器电路图

　　230V(AC)/50Hz 75W TRIAC调光LED驱动器材料清单(BOM):