Abstract: An external and redundant power device provides external electric powers and redundant electric powers. The external and redundant power device includes power supply units, a power integrated circuit, a power output control circuit and a controller. The power supply units provide input power streams. The power integrated circuit further integrates the input power to a whole power supply and converts a whole power supply first part into a first power. The power output control circuit acquires the whole power supply and respectively output preset power streams to the power receiving devices. The controller controls the power output control circuit outputting the preset power streams according to a whole power supply status and a connection condition.

Abstract: A computer system includes at least one mother board and a number of control cards monitored by the motherboard via an I2C bus. Each control card has a unique ID. The computer system connects one of the control cards to the I2C bus using a card control device installed in each of the control cards to monitor each of the control cards via the single I2C bus.

Abstract: A powered device is electronically connected to a power sourcing equipment, and includes a powered circuit, a receiving unit and at least one rectifier circuit. Each rectifier circuit includes a rectifier unit, an auxiliary power unit, a polarity determining unit, a control unit and a selecting unit. The rectifier unit provides a current flow between the receiving unit and the powered circuit. The auxiliary power unit provides an auxiliary power signal. The polarity determining unit detects the polarity of voltage signal, to generate a determining signal. The control unit outputs a control signal according to the auxiliary power signal and the determining signal. The selecting unit connects the positive input of the powered circuit to a receiving end whose output voltage is positive according to the control signal, to lower power of rectification. A rectifier circuit is also provided.

Abstract: A powered device is electronically connected to a power sourcing equipment, and includes a powered circuit, a receiving unit and at least one rectifier circuit. Each rectifier circuit includes a rectifier unit, an auxiliary power unit, a polarity determining unit, a control unit and a selecting unit. The rectifier unit provides a current flow between the receiving unit and the powered circuit. The auxiliary power unit provides an auxiliary power signal. The polarity determining unit detects the polarity of voltage signal, to generate a determining signal. The control unit outputs a control signal according to the auxiliary power signal and the determining signal. The selecting unit connects the positive input of the powered circuit to a receiving end whose output voltage is positive according to the control signal, to lower power of rectification. A rectifier circuit is also provided.

Abstract: A power off delay circuit includes a first diode with an anode receiving input power and a boost transformer circuit connected to a cathode of the first diode. The boost transformer circuit outputs power signals to a load circuit, and includes a capacitor, a primary winding, a first secondary winding, and a second secondary winding. The capacitor is charged when an input power is on, and discharges when the input power is off. The first secondary winding boosts power flowing through the primary winding and the first switch branch to charge the capacitor via the third switch branch when the input power is on. The capacitor discharges via the second secondary winding and the fourth switch branch when the input power is off, and the primary winding boosts discharging power of the capacitor, and outputs boosted discharging power to the load circuit via the second switch branch.

Abstract: A computer system includes at least one mother board and a number of control cards monitored by the motherboard via an I2C bus. Each control card has a unique ID. The computer system connects one of the control cards to the I2C bus using a card control device installed in each of the control cards to monitor each of the control cards via the single I2C bus.

Abstract: A current balance circuit includes a first branch and a second branch in parallel between a power supply unit and at least one load, which respectively include a switch. The current balance circuit detects and compares currents flowing through the first branch and the second branch. The current balance circuit also generates triangle waves and reversed triangle waves, compares voltage of a control pole of a first switch with the triangle waves, and compares voltage of the control pole of a second switch with the reversed triangle waves. Then the current balance circuit controls if the triangle waves and the reversed triangle waves are input to the first switch and the second switch according to the currents flowing through the first branch and the second branch to adjust impedance of the first switch and the second switch to balance the currents flowing through the first branch and the second branch.

Abstract: A current balance circuit includes a first branch and a second branch in parallel between a power supply unit and at least one load, which respectively include a switch. The current balance circuit detects and compares currents flowing through the first branch and the second branch. The current balance circuit also generates triangle waves and reversed triangle waves, compares voltage of a control pole of a first switch with the triangle waves, and compares voltage of the control pole of a second switch with the reversed triangle waves. Then the current balance circuit controls if the triangle waves and the reversed triangle waves are input to the first switch and the second switch according to the currents flowing through the first branch and the second branch to adjust impedance of the first switch and the second switch to balance the currents flowing through the first branch and the second branch.

Abstract: A power off delay circuit includes a first diode with an anode receiving input power and a boost transformer circuit connected to a cathode of the first diode. The boost transformer circuit outputs power signals to a load circuit, and includes a capacitor, a primary winding, a first secondary winding, and a second secondary winding. The capacitor is charged when an input power is on, and discharges when the input power is off. The first secondary winding boosts power flowing through the primary winding and the first switch branch to charge the capacitor via the third switch branch when the input power is on. The capacitor discharges via the second secondary winding and the fourth switch branch when the input power is off, and the primary winding boosts discharging power of the capacitor, and outputs boosted discharging power to the load circuit via the second switch branch.