| 摘要 |
PROBLEM TO BE SOLVED: To provide a video doorphone system that can supply required minimum current to a control of each device, in a standby state. SOLUTION: A master unit monitor 2 is provided with a master unit monitor power supply circuit 25, that supplies power to a master unit monitor control circuit 22, when the video doorphone system is at a standby and with a master unit monitor power supply changeover control circuit 26, that switches an over- current setting of the master unit monitor power supply circuit 25, when the video doorphone system shifts from the standby state to an image output call state. An extended master unit monitor 3a is provided with an extended master unit monitor power supply circuit 35a, that supplies power to an extended master unit monitor control circuit 32a, when the video doorphone system is at standby, and with an extended master unit monitor power supply mode changeover control circuit 36a, that switches the over-current setting of the extended master unit monitor power supply circuit 35a, when the video doorphone system shifts from the standby state to the image output call state. |
