Patent ID: 7859326
Filing Date: 2010-12-28
Classification: H02M

Abstract:
1. A power supply device comprising, a first power supply unit including: a second power supply unit including: wherein the first power supply unit is operated in the first mode transmitting the first periodic signal via the first signal transmission path and the second signal transmission path, and wherein the second power supply unit is operated in the second mode transmitting the another second periodic signal input from the another first external terminal via the another third signal transmission path, wherein the first external terminal of the first power supply unit and the another first external terminal of the second power supply unit are connected, wherein the third signal transmission path of the first power supply unit has an operation transmitting in phase the second periodic signal input from the first external terminal in the second mode corresponding to the operation control signal, and an operation inverting and transmitting the first periodic signal, wherein the another third signal transmission path of the second power supply unit has an operation transmitting in phase the another second periodic signal input from the another first external terminal in the second mode corresponding to the operation control signal, and an operation inverting and transmitting the first periodic signal wherein the oscillation circuit of the first power supply unit receives the potential of a first capacitor connected to a second external terminal to switch charge/discharge operation so that the potential of the first capacitor is changed between a first threshold voltage and a second threshold voltage by an output signal of a voltage comparison circuit having hysteresis characteristics including the first threshold voltage and the second threshold voltage higher than the first threshold voltage, wherein the first power supply unit further comprises a voltage judge circuit, wherein the voltage judge circuit forms the operation control signal setting the first mode when the potential of the first capacitor is within the range of the first threshold voltage and the second threshold voltage, wherein the voltage judge circuit forms the operation control signal transmitting in phase the second periodic signal input from the first external terminal in the second mode when the potential of the first capacitor is lower than the first threshold voltage, wherein the voltage judge circuit forms the operation control signal inverting and transmitting the second periodic signal input from the first external terminal in the second mode when the potential of the first capacitor is higher than the second threshold voltage, wherein the oscillation circuit of the second power supply unit receives the potential of another first capacitor connected to another second external terminal to switch charge/discharge operation so that the potential of the another first capacitor is changed between another first threshold voltage and another second threshold voltage by another output signal of a another voltage comparison circuit having hysteresis characteristics including the another first threshold voltage and the another second threshold voltage higher than the another first threshold voltage, wherein the second power supply unit further comprises another voltage judge circuit, wherein the another voltage judge circuit forms the another operation control signal setting the first mode when the potential of the another first capacitor is within the range of the another first threshold voltage and the another second threshold voltage, wherein the another voltage judge circuit forms the another operation control signal transmitting in phase the another second periodic signal input from the another first external terminal in the second mode when the potential of the another first capacitor is lower than the another first threshold voltage, and wherein the another voltage judge circuit forms the another operation control signal inverting and transmitting the another second periodic signal input from the another first external terminal in the second mode when the potential of the another first capacitor is higher than the another second threshold voltage.