High-voltage startup circuit

摘要

A system including a power transistor configured to receive an alternating current (AC) line voltage and a control circuit. During a rising portion of a half cycle of the AC line voltage, the control circuit is configured to turn on the power transistor when the AC line voltage reaches a first value and turn off the power transistor when the AC line voltage reaches a second value. The second value is greater than the first value. During a falling portion of the half cycle, the control circuit is configured to turn on the power transistor when the AC line voltage reaches the second value and turn off the power transistor when the AC line voltage reaches the first value.

主权项

1. A system comprising:
a power transistor configured to receive an alternating current (AC) line voltage; and a control circuit configured to
during a rising portion of a half cycle of the AC line voltage, turn on the power transistor when the AC line voltage reaches a first value and turn off the power transistor when the AC line voltage reaches a second value, wherein the second value is greater than the first value, andduring a falling portion of the half cycle, turn on the power transistor when the AC line voltage reaches the second value and turn off the power transistor when the AC line voltage reaches the first value.