Abstract: The present invention relates to compounds of formula (I) wherein Q is selected from O or S; R1 is a saturated or unsaturated, optionally substituted hydrocarbyl group optionally including one or more heteroatoms N, O or S; R2 is a cyclic group substituted at the a and a? positions, wherein the substituent at the ?-position is a monovalent heterocyclic group or a monovalent aromatic group, wherein the heterocyclic or aromatic group may optionally be substituted, and wherein the cyclic group may optionally be further substituted; R3 and R4 are each independently hydrogen, halogen, —OH, —NH2, —CN, —R5, —OR5, —NHR5 or —N(R5)2; or R3 and R4 together with the carbon atom to which they are attached may form a 3- to 7-membered saturated or unsaturated, optionally substituted cyclic group; and R5 is independently optionally substituted C1-C4 alkyl.

Abstract: The present invention discloses a switching power converter with low common mode noise. The switching power converter comprises at least a switch with at least a terminal wherein said switch turning on and off alternatively which generates a plurality of noise voltages, and the noise voltage having a jump point and a static point wherein the jump point is one of said inductive component terminals, the capacitive component terminals and the second and third terminal of the switch; and an additional impedance connected between the static point and the jump point of different noise voltage to neutralize common noise current. In addition, another switching power converter having primary side and secondary side can be used to reduce the common mode noise by adding some additional impedance between the static points and jump points of the primary side and secondary side.

Abstract: The present invention discloses a power converter with low common mode noise. The power converter having a primary side and a secondary side, comprises a transformer having a primary winding and a secondary winding, and at least one electrostatic shield disposed between the primary winding and the secondary winding, wherein the electrostatic shield is configured with partial first region of the primary winding and partial second region of the secondary winding such that the electrostatic shield partially shields with the primary winding and the secondary winding to reach the purpose of suppressing the common mode noise. In addition, another method can be used to reduce the common mode noise of a power converter having primary side and secondary side, which is adding some additional impedance between the static points and jump points of the primary side and secondary side.

Abstract: The present invention discloses a switching power converter with low common mode noise. The switching power converter comprises at least a switch with at least a terminal wherein said switch turning on and off alternatively which generates a plurality of noise voltages, and the noise voltage having a jump point and a static point wherein the jump point is one of said inductive component terminals, the capacitive component terminals and the second and third terminal of the switch; and an additional impedance connected between the static point and the jump point of different noise voltage to neutralize common noise current. In addition, another switching power converter having primary side and secondary side can be used to reduce the common mode noise by adding some additional impedance between the static points and jump points of the primary side and secondary side.

Abstract: The present invention discloses a power converter with low common mode noise. The power converter having a primary side and a secondary side, comprises a transformer having a primary winding and a secondary winding, and at least one electrostatic shield disposed between the primary winding and the secondary winding, wherein the electrostatic shield is configured with partial first region of the primary winding and partial second region of the secondary winding such that the electrostatic shield partially shields with the primary winding and the secondary winding to reach the purpose of suppressing the common mode noise. In addition, another method can be used to reduce the common mode noise of a power converter having primary side and secondary side, which is adding some additional impedance between the static points and jump points of the primary side and secondary side.