LINE VOLTAGE DETECTION CIRCUIT

摘要

A first filter outputs a first signal in response to receiving an input signal. The first signal has a first state in response to the input signal reaching a first threshold voltage on a leading edge of the input signal, and a second state in response to the input signal reaching the first threshold voltage on a trailing edge of the input signal. A second filter outputs a second signal in response to receiving the input signal. The second signal has the first state in response to the input signal reaching a second threshold voltage on the leading edge of the input signal, and the second state in response to the input signal reaching the second threshold voltage on the trailing edge of the input signal. A detection circuit determines, based on times when the first and second thresholds are reached, whether the input signal is received from a triac.

主权项

1. A system comprising:
a first filter configured to
output a first signal in response to receiving an input signal,wherein the first signal has a first state in response to the input signal reaching a first threshold voltage on a leading edge of the input signal, andwherein the first signal has a second state in response to the input signal reaching the first threshold voltage on a trailing edge of the input signal; a second filter configured to
output a second signal in response to receiving the input signal,wherein the second signal has the first state in response to the input signal reaching a second threshold voltage on the leading edge of the input signal, andwherein the second signal has the second state in response to the input signal reaching the second threshold voltage on the trailing edge of the input signal; and a detection circuit configured to determine, based on times at which the first threshold and the second threshold are reached on the leading edge of the input signal or the trailing edge of the input signal, whether the input signal is received from a triac.