microchip公司的CL88020是離線LED驅(qū)動器,輸入電壓120VAC,提供8.5W LED功率.器件包括CL88020 LED驅(qū)動器,六個電阻和橋式整流器.具有可編超溫保護(hù),允許THD優(yōu)厚,可選擇降低輕負(fù)載輸出波紋,只使用一個外接陶瓷存儲電容,TRIAC調(diào)光兼容,主要用在LED燈和LED照明固定裝置.本文介紹了CL88020主要特性,框圖和典型應(yīng)用電路,以及120VAC離線LED驅(qū)動器板ADM00766和LED負(fù)載板ADM00767主要特性,電路圖,材料清單和PCB設(shè)計圖.

The CL88020 LED Driver Integrated Circuit (IC) is anoff-line sequential linear LED driver designed to provide8.5W of LED power from a 120 VAC nominal inputvoltage.

CL88020 is designed to drive a long string of inexpensive,low-current LEDs directly from the AC mains. Abasic driver circuit consists of Microchip TechnologyInc.’s CL88020 LED driver IC, six resistors and a bridgerectifier. Two to four additional components are optionalfor various levels of transient protection, also with alow-cost NTC to assure remote overtemperature protection(OTP). No capacitors, EMI filters, or power factorcorrection circuits are needed unless the optionalreduced light output ripple feature is desired.

A string of series/parallel LEDs is tapped at four locations.Four linear current regulators sink current at eachtap through a single control point and are sequentiallyturned on and off. High efficiency is achieved by shuttingoff upstream regulators when downstream regulatorsachieve regulation. This makes controlling overall input current easier than trying to control multiple currentpaths, thereby tracking the input sine wave voltage.

CL88020 uses a self-commutation techniqueusing only the tap currents themselves; this techniqueinherently provides smooth transitions from one regulatorto the next, without relying on tap voltages or therectified AC to coordinate the transitions.

CL88020主要特性:

? Optimized for 120 VAC Nominal Input Voltage
- 120VAC ± 15% input voltage
? Targeted for 8.5W Output Power
? Programmable Overtemperature Protection
- Provides Gradual Reduction in Light Outputwith Increasing Temperature
? Active Line Regulation
- Provides Fairly Constant Output Power overVariations in AC Line Voltage
- Typical Line Regulation of –12% to +0%
? Four Taps with Two Current Set Resistors
- Allows Optimization of THD
? Optional Reduced Light Output Ripple
- Provides Continuous Power to the LED
- Eliminates Strobing
- Uses an External Ceramic Storage Capacitor
? TRIAC Dimmer Compatible
? Available in a Thermally Enhanced 8-Lead SOICPackage with Heat Slug
- Larger Creepage Distances between HighVoltage and Low Voltage Pins

CL88020應(yīng)用:

? LED Lamps
? LED Lighting Fixtures

圖1.CL88020框圖

圖2.CL88020典型應(yīng)用電路圖

CL88020 120VAC離線LED驅(qū)動器板ADM00766和LED負(fù)載板ADM00767 The CL88020 120 VAC Offline LED Driver Evaluation Board is a complete solution consistingof an LED Driver (ADM00766) and an LED Load Board (ADM00767) powered directly from the 120VAC line and based on Microchip Technology’s CL88020 sequential linear LED driver. The application achieves efficient operation without using anymagnetics or conventional switching techniques and is a flexible solution that allowsusers to design and to test their own LED Load solution. The included LED Load ismade with 10 LEDs. Since no high frequencies are present, it exhibits inherently lowconducted and radiated EMI without needing input filters or shielding. Because the currentthrough the LEDs follows the AC input voltage, PFC circuitry is also not needed.

The CL88020 is inherently compatible with both leading-edge and trailing-edge dimmers,with no need for special circuitry to detect and respond to them.The LED Load is provided on a double-layer 60 mm diameter FR4 PCB (0.6 mm thick)mounted on a pin-fin heat sink. The LED Driver PCB (ADM00766) is made on 1.6 mm standard double-layer FR4. The kit includes an 8-wire flat cable to connect the LEDDriver Board to the LED Load, and a black anodized pin fin heat sink with double-sidedadhesive thermal tape necessary to mount the LED Load Board on it. All circuitry andhardware is provided, along with transient protection and overtemperature protection.Just plug into a 120 VAC outlet (50 Hz or 60 Hz) to get started.

LED驅(qū)動器評估板ADM00766主要特性:

? Input Voltage: 120 Vrms +/-15%, 50/60 Hz
? Typical Output Capability: up to 130 mA
? Efficiency: Over 83%
? Max Output Power: 8.5W (depends on the cooling provided)
LED負(fù)載板ADM00767主要特性:
? Contains 10 LEDs (GW P9LR31.EM) grouped in 4 taps
? An 8-wire flat cable input connector
? One NTC for overtemperature protection
CL88020 120VAC離線LED器評估板套件包括:
? CL88020 LED Driver Evaluation Board (ADM00766)
? 8-wire interconnection flat cable
? 4 nylon stand-offs with corresponding screw
? Important Information Sheet
CL88020LED負(fù)載板ADM00767包括:
? CL88020 LED Load Board (ADM00767)
? LED Load pin fin heat sink
? Thermal double-sided adhesive tape
? Important Information Sheet

圖3.CL88020 120VAC離線LED器評估板(源板)外形圖

圖4.CL88020 LED負(fù)載板外形圖

圖5.連接圖

圖6.LED驅(qū)動器評估板ADM00766電路圖

圖7.CL88020離線LED驅(qū)動器應(yīng)用電路
LED驅(qū)動器評估板ADM00766材料清單:

L88020 LED負(fù)載板材料清單:

圖8.L88020LED驅(qū)動器評估板ADM00766PCB設(shè)計圖(1)

圖9.L88020LED驅(qū)動器評估板ADM00766PCB設(shè)計圖(2)

圖10.L88020LED驅(qū)動器評估板ADM00766PCB設(shè)計圖(3)

圖11.L88020 LED驅(qū)動器評估板ADM00766PCB設(shè)計圖(4)

圖12.L88020 LED驅(qū)動器評估板ADM00766PCB設(shè)計圖(5)

圖13.L88020 LED驅(qū)動器評估板ADM00766PCB設(shè)計圖(6)

圖14.L88020 LED負(fù)載板ADM00767 PCB設(shè)計圖(1)

圖15.L88020 LED負(fù)載板ADM00767 PCB設(shè)計圖(2)

圖16.L88020 LED負(fù)載板ADM00767 PCB設(shè)計圖(3)

圖17.L88020 LED負(fù)載板ADM00767 PCB設(shè)計圖(4)

圖18.L88020 LED負(fù)載板ADM00767 PCB設(shè)計圖(5)

圖19.L88020 LED負(fù)載板ADM00767 PCB設(shè)計圖(6)