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LP8866-Q1: Discuss LP8866 PWM mode vs Current mode

Part Number: LP8866-Q1

Hi Team,

目前測試LP8866的PWM模式和電流模式

輸入電流在 PWM模式時約為1.5A  ,輸入電流在電流模式約為1.2A

 輸出電壓在PWM模式 為25.6V

 輸出電壓在電流模式為21V

 想請教,在同樣的SCH和測試條件下,其輸出LED設置是8串2並,為何會有這樣差異?理論上電壓應該要相同對嗎?

  • Hi, Kygo, 

    1. PWM 模式时效率会相对电流模式低一些, 由于负载在空载与满载间切换。 电流模式为恒定负载。 

    2. 电流模式时, LED VF 对应值为平均电流的VF, PWM 时, LED VF 对应值为Iset 时的VF值。 

          For example: LED XLamp ML-C VF is 3.0V@50mA, 3.3V@100mA; 

    Regards, 

    Xiaoguang