Patent ID: 8450993

Claim:
A semiconductor buck circuit with floating-voltage suppression, comprising: a first semiconductor buck element ( 101 ) having an anode and an output end; a second semiconductor buck element ( 102 ) having an anode and an output end; and a shunting current load ( 103 ) having an anode and an output end, wherein: the anode of the first semiconductor buck element ( 101 ) is connected to an anode of a direct current power supply (V 1 ) and the output end of the first semiconductor buck element ( 101 ) is connected to the anode of the second semiconductor buck element ( 102 ) and the anode of the shunting current load, whereby the first semiconductor buck element ( 101 ) is forward series connected between the anode of the direct current power supply (V 1 ) and respective anodes of the second semiconductor buck element ( 102 ) and the shunting current load ( 103 ), the output end of the shunting current load ( 103 ) is connected to a cathode of a DC output power supply (V 2 ), and the output end of the second semiconductor buck element ( 102 ) is connected to an anode of the DC output power supply V 2 , wherein said shunting current load ( 103 ) limits a voltage drop across the DC output power supply (V 2 ) in response to a decrease in input voltage from the direct current power supply (V 1 ), wherein the first semiconductor buck element ( 101 ) and the second semiconductor buck element ( 102 ) each include series, parallel, or series-parallel connected diodes or LEDs and at least one Zener diode, and wherein the shunting current load includes at least one of a resistive element, an LED, and a combination of at least one resistive element and at least one LED, and wherein the second semiconductor buck element ( 102 ) is connected in series with at least one Zener diode, and a Zener voltage of the at least one Zener diode in a normal state is higher than a voltage of the DC output power supply (V 2 ).