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RD0801

Figure 10.5: Inductor saturation: CH1 is the LO voltage, CH2 is the VS voltage, CH3 is the current

through the resonant inductor, and CH4 is the voltage across the lamp

Figure 10.6 shows the VS voltage and the voltage across the lamp when the IC

undergoes reset with a lamp exchange. When the lamp is removed, crest factor

protection is triggered, and the IC enters the Fault mode and shuts down. Since the lamp

is removed, LO pins is pulled above VLOSD+, and the IC goes to UVLO mode. When

the lamp is re-inserted, the IC goes back to the Preheat / Ignition mode, and the half-

bridge starts to oscillate again.

Figure 10.6: Lamp exchange: CH1 is the LO voltage, CH2 is the VS voltage, and CH4 is the voltage

across the lamp