Patent ID: 7173664

Claim:
An image signal processor connected between a solid-state imaging device, which generates a first image signal, and an external device, the image signal processor comprising: a first regulator supplied with a power supply voltage to generate a first regulated voltage that is in accordance with an output level of the solid-state imaging device; a second regulator supplied with the power supply voltage to generate a second regulated voltage that is in accordance with an input level of the external device; a switch circuit connected to the second regulator to select either one of the power supply voltage and the second regulated voltage in accordance with the operating state of at least one of the solid-state imaging device and the external device; a signal processing circuit connected to the solid-state imaging device and the first regulator, supplied with the first regulated voltage from the first regulator, for operating with the first regulated voltage, wherein the signal processing circuit receives the first image signal from the solid-state imaging device, performs a predetermined signal processing on the first image signal, and generates a second image signal that complies with a predetermined format; and an output circuit connected to the switch circuit and the signal processing circuit, for operating with the one of the power supply voltage and the second regulated voltage selected by the switch circuit, wherein the output circuit provides the second image signal to the external device, wherein the signal processing circuit is supplied with the first regulated voltage and the output circuit is supplied with the second regulated voltage when the solid-state imaging device is operating, and the signal processing circuit is supplied with a voltage at a ground level and the output circuit is supplied with the power supply voltage when the solid-state imaging device stops operating while the external device is operating.