LED照明的控制IC,具有兩種工作模式:臨界導(dǎo)通模式(CRM)和固定開關(guān)頻率模式.CRM模式能精確地控制LED電流和修正功率因素,具有高效率,而固定開關(guān)頻率模式能大大地降低外接元件數(shù)量.本文介紹了兩種工作模式連接框圖, R2A20134SP多種評估板主要特性,以及R2A20134EVB-NN1E評估板特性,電路圖,元件數(shù)值計算方法,110VAC和220VAC的材料清單和PCB元件布局圖.

R2A20134SP is a control IC for LED lighting. It has two operation modes, Critical Conduction mode (CRM) and fixed switching frequency mode. User can choose one suitable mode for their purpose.

At Critical Conduction mode (CRM), this IC can control LED current precisely and correct power factor and achieve high efficiency by zero-current switching. At Fixed-Frequency mode, user can reduce the external components dramatically. AT Peak Current Control mode applying Fixed Switching Frequency Mode realized the minimum numbers of external components, smallest packaging and low BOM cost. Also this allows the isolated flyback operation.


圖1.R2A20134SP臨界導(dǎo)通模式(Rrt接地)框圖

圖2.R2A20134SP固定開關(guān)頻率模式(Rrt接Vref)框圖

圖3.R2A20134SP峰值電流控制電路圖

圖4.R2A20134SP恒定ON時間控制(PFC)電路圖
R2A20134SP多種評估板特一攬表:


圖5. R2A20134EVB-NN1E評估板外形圖

圖6. R2A20134EVB-NN1E評估板電路圖(誤差放大器控制)

R2A20134EVB-NN1E評估板主要元件計算表:




R2A20134EVB-NN1E (誤差放大器控制)材料清單(BOM):
Vin = AC85-132 V, Vf = 65 V, ILED = 100 mA

AC220 V input, VF = 35 V, ILED = 400 mA變更的元件數(shù)值:


圖7. R2A20134EVB-NN1E評估板元件布局圖:左:頂層;右:底層
詳情請見:
http://documentation.renesas.com/doc/products/linear/r03ds0033ej_r2a20134sp.pdf
和
http://documentation.renesas.com/doc/products/linear/apn/r03an0004ej0200_r2a20134sp.pdf