5

AT9933DB1

Fig. 6. LED current during step changes in the input voltage

Channel 1(blue): Input Voltage (10V/div)

Channel 4 (green): LED current (100mA/div)

(a): Open LED Condition

(b): Output Short Circuit

Fig. 7. HV9930DB1 during output fault conditions

FET drain Voltage (20V/div) (Channel 1 in (a); Channel 2 in (b)

Channel 4 (green): LED current

Short Circuit

(a)

(b)

(c)

Fig. 8. PWM Dimming at 100Hz

Channel 1 (blue): PWM Dimming Input Signal (2V/div)

Channel 4 (Green): LED current (100mA/div)