| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a technique for stabilizing operations at turning on/off of a power supply by a simple configuration in an optical receiver and amplifier and a photocoupler. <P>SOLUTION: An optical receiver and amplifier includes: a photodiode which generates a photocurrent in response to a received light input; an output section which outputs an output voltage being a low level or a high level in accordance with a magnitude of the photocurrent by using a power supply voltage supplied from a power supply; and an output control circuit which controls an input voltage of the output section such that the output voltage is set to the low level when the power supply is turned on or off during a period where the power supply voltage is lower than a predetermined value. According to thus configured optical receiver and amplifier, the output control circuit can set the output voltage of an output transistor to the low level equal to or lower than a predetermined power supply voltage regardless of presence/absence of light output, so that a control circuit for preventing malfunction is not needed. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
