| 摘要 |
A dimmer conduction angle detection circuit, and systems and methods incorporating the same, is disclosed. The circuit receives a gate drive signal from a PFC circuit and provides a dimmer reference level signal representative of a dimmer circuits dimmer setting in response. The circuit includes a comparator with first and second inputs that provides a pulse-width modulated output in response to comparing signals received at the inputs. The pulse-width modulated output has a pulse width representative of the dimmer circuits dimmer setting. The circuit also includes an input network, coupled to the comparator, to receive the gate drive signal and to provide an output, in response, to the comparators first input. The circuit also includes a threshold supply circuit to provide a threshold voltage to the comparators second input, and a filter, coupled to the comparator, to convert the comparators pulse-width modulated output to the dimmer reference level signal. |
