Power supply for a two-wire smart switch and lighting loads thereof

1. A power supply powered by main electricity for a two-wire or three-wire smart switch, connected to at least one lighting load, to control the power on and power off of the at least one lighting load, the power supply comprises:

a first low power module;

a second low power module;

a third low power module;

a high power module;

a current sensing module;

a low power lighting load adapter;

wherein:

if the smart switch has a two-wire configuration and a first one of the least one lighting load is a low power lighting load, the low power lighting load adapter is connected in parallel to the first one of the at least one lighting load and AC power from the main electricity will flow from the first one of the at least one lighting load and the low power lighting load adapter to the low power module when the first one of the least one lighting load is in an off state;

if the smart switch has a two-wire configuration and the first one of the at least one lighting load is not a low power lighting load, the low power lighting load adapter is not connected to the first one of the at least one lighting load and the AC power will flow from the first one of the at least one lighting load to the low power module when the first one of the at least one lighting load is in an off state,

if the smart switch has a three-wire configuration, the AC power will flow from a neutral and a phase wires to the first low power module;

the first low power module converts the AC power from the main electricity into a first level DC voltage and outputs the first level DC voltage to the second low power module;

the second low power module converts the first level DC voltage from the first low power module into a second level DC voltage when the first one of the at least one lighting load is in an off state;

the high power module turns on the at least one lighting load, when a respective one of at least one activation signal is received from an external controller module that is powered by the second low level DC voltage, and a shunt current flows out of the high power module when the at least one lighting load is in an on state;

the third low power module receives the shunt current and uses it to output the first level DC voltage to the second low power module when the first one of the at least one lighting load is in an on state;

the second low power module converts the first level DC voltage from the third low power module into a second level DC voltage when the first one of the at least one lighting load is in an on state;

the current sensing module is powered by the second level DC voltage and converts the shunt current from the high power module into a current-voltage signal to be outputted to the external controller module.

2. The power supply of claim 1 , wherein the two-wire configuration consists of a phase wire and a wire from the lighting load.

3. The power supply of claim 1 , wherein the three-wire configuration consists of a phase wire, a neutral wire and a wire from the lighting load.

4. The power supply of claim 1 , wherein the first low power module comprises a selector switch to select between the two-wire or three-wire configurations.

5. The power supply of claim 1 , wherein the at least one lighting load is one lighting load.

6. The power supply of claim 1 , wherein the at least one lighting load are two lighting loads.

7. The power supply of claim 1 , wherein the at least one lighting load are three lighting loads.

8. The power supply of claim 1 , wherein the at least one lighting load is a resistive lighting load, a CFL lighting load, an LED lighting load or a combination thereof.

9. The power supply of claim 1 , wherein the low power lighting load adapter comprises one of a resistive adapter, a capacitive adapter, an inductive adapter or a combination thereof.

10. The power supply of claim 1 , wherein the switching of the on and off states of the at least one lighting load in the high power module is performed via at least one bidirectional semiconductor device.

11. The power supply of claim 1 , wherein the at least one activation signal is electrically isolated from the main electricity.

12. A power supply powered by main electricity for a two-wire or three-wire smart switch, connected to at least one lighting load, to control the power on and power off of the at least one lighting load, the power supply comprises:

a low power module;

a high power module;

a current sensing module;

a low power lighting load adapter;

a zero detection crossing module;

wherein:

if the smart switch has a two-wire configuration and a first one of the least one lighting load is a low power lighting load, the low power lighting load adapter is connected in parallel to the first one of the at least one lighting load and AC power from the main electricity will flow from the first one of the at least one lighting load and the low power lighting load adapter to the low power module when the first one of the least one lighting load is in an off state;

if the smart switch has a two-wire configuration and the first one of the at least one lighting load is not a low power lighting load, the low power lighting load adapter is not connected to the first one of the at least one lighting load and the AC power will flow from the first one of the at least one lighting load to the low power module when the first one of the at least one lighting load is in an off state;

if the smart switch has a three-wire configuration, the AC power will flow from a neutral and a phase wire of the main electricity to the low power module;

the low power module converts the AC power from the main electricity into a low level DC voltage;

the high power module turns on the at least one lighting load for less than a half cycle of the main electricity, when a respective one of at least one activation signal is received from an external controller module that is powered by the low level DC voltage, and a shunt current flows out of the high power module when the at least one lighting load is in an on state;

the zero crossing module outputs a zero crossing signal to the external controller module when a wave of the AC main voltage crosses zero volts, for the external controller module to synchronize the timing and delay of the activation signal with the phase of the main electricity;

the current sensing module is powered by the low level DC voltage and converts the shunt current from the high power module into a current-voltage signal to be outputted to the external controller module; and

the low power module, the high power module, the current sensing module and the zero crossing detecting module are galvanically isolated from the main electricity.

13. The power supply of claim 12 , wherein the two-wire configuration consists of a phase wire and a wire from the at least one lighting load.

14. The power supply of claim 12 , wherein the three-wire configuration consists of a phase wire, a neutral wire and a wire from the at least one lighting load.

15. The power supply of claim 12 , wherein an input selector is able to automatically select between the two-wire or three-wire configurations.

16. The power supply of claim 12 , wherein the at least one lighting load is one lighting load.

17. The power supply of claim 12 , wherein the at least one lighting load are two lighting loads.

18. The power supply of claim 12 , wherein the at least one lighting load are three lighting loads.

19. The power supply of claim 12 , wherein the at least one lighting load is a resistive lighting load, a CFL lighting load, an LED lighting load or a combination thereof.

20. The power supply of claim 12 , wherein the low power lighting load adapter comprises one of a resistive adapter, a capacitive adapter, an inductive adapter or a combination thereof.

21. The power supply of claim 12 , wherein the switching of the on and off states of the at least one lighting load in the high power module is performed via at least one bidirectional semiconductor device.