SLUUBZ9 May   2020 TPS92200

 

  1.   TPS92200D1/D2EVM 30-V, 1.5-A Buck LED Driver Evaluation Module
    1.     Trademarks
    2. 1 Introduction
    3. 2 Warnings and Cautions
    4. 3 Description
      1. 3.1 Typical Applications
      2. 3.2 Test Setup
        1. 3.2.1 Connector Description
        2. 3.2.2 Input/Output Connection
    5. 4 Performance Data and Typical Characteristics Curves
      1. 4.1 Efficiency
      2. 4.2 Line Regulation
      3. 4.3 Load Regulation
      4. 4.4 Analog Dimming
      5. 4.5 PWM Dimming Waveforms
    6. 5 Schematic
    7. 6 TPS92200D1/D2EVM PCB Layout
    8. 7 Bill of Materials

4.1 Efficiency

Figure 1 shows the efficiency versus VDIM in analog dimming mode. The maximum LED current is 1.5 A when the VDIM is 1.2V. VIN = 12 V, and an infrared (IR) LED load is used. The typical forward voltage of an IR LED is 1.7 V at 1.5 A. The LED number in series is 1, 3, and 5, respectively.

D1AnalogEfficiency.gifFigure 1. Efficiency vs. VDIM in Analog Dimming Mode(TPS92200D1), 1.5 A at VDIM>=1.2V, VIN = 12 V

Figure 2 shows the efficiency versus PWM Duty Cycle in PWM dimming mode. PWM frequency is 500hz, LED current is set at 1.0 A. 6 White LEDs are used. The typical forward voltage of a White LED is 3 V at 1 A.

D1PWMEfficiency.gifFigure 2. Efficiency vs. PWM Duty Cycle in PWM Dimming Mode(TPS92200D1), 1.0 A at 100% Duty

Figure 3 shows the efficiency versus PWM Duty Cycle in Analog dimming mode. PWM frequency is 50khz, LED current is set at 1.0 A. two IR LEDs are used. The typical forward voltage of a White LED is 1.65 V at 1 A.

D2AnalogEfficiency.gifFigure 3. Efficiency vs. PWM Duty Cycle in Analog Dimming Mode(TPS92200D2)