Patent ID: 7880811

Claim:
A signal separation circuit separating a plurality of pulse signals received via the same signal line, the signal separation circuit comprising: a first circuit detecting a first pulse signal with a first pulse width from a signal received via the signal line to generate a first output signal corresponding to the first pulse signal; a second circuit detecting a second pulse signal with a second pulse width shorter than the first pulse width from the received signal; and a third circuit generating a second output signal from the first output signal and an output signal of the second circuit, wherein the first circuit comprises a first integration circuit which is charged beyond a first threshold voltage by the first pulse signal and is not charged up to the first threshold voltage by the second pulse signal; and a first output circuit generating the first output signal when the first integration circuit is charged beyond the first threshold voltage, the second circuit comprises a second integration circuit which is charged beyond a second threshold by the second pulse signal and the third circuit comprises a second output circuit generating the second output signal when the first circuit does not generate the first output signal in an end edge timing of the input pulse signal which contributes to the charge of the second integration circuit after the second integration circuit is charged beyond the second threshold voltage.