Power supply path structure of flexible circuit board

1. A power supply path structure of a flexible circuit board, comprising:

a first flexible circuit board comprising a first connection section, a first opposite connection section, and a first extension section connected between the first connection section and the first opposite connection section and extending in an extension section, wherein the first flexible circuit board has a first surface comprising at least one first connection pad formed thereon in the first connection section and at least one first opposite connection pad formed thereon in the first opposite connection section and the first connection pad and the first opposite connection pad are electrically connected to each other through a first power supply path extending across the first extension section; and

a second flexible circuit board comprising a second connection section, a second opposite connection section, and a second extension section connected between the second connection section and the second opposite connection section, wherein the second flexible circuit board has a second surface comprising at least one second connection pad formed thereon in the second connection section and at least one s econd opposite connection pad formed thereon in the second opposite connection section and the second connection pad and the second opposite connection pad are electrically connected to each other through a second power supply path extending across the second extension section;

wherein the second flexible circuit board is arranged to correspond to and is stacked on the first flexible circuit board;

the second connection pad of the second flexible circuit board corresponds to the first connection pad of the first flexible circuit board and the second connection pad is electrically connected through a first electric conduction structure with the first connection pad;

the second opposite connection pad of the second flexible circuit board corresponds to the first opposite connection pad of the first flexible circuit board and the second opposite connection pad is electrically connected through a second electric conduction structure with the first opposite connection pad; and

the first power supply path and the second power supply path form a parallel-connected power supply path for the flexible circuit board.

2. The power supply path structure as claimed in claim 1 , wherein:

the second flexible circuit board comprises a first through hole formed in and extending through the second connection pad and the first electric conduction structure is deposited and fixed in the first through hole; and

the second flexible circuit board comprises a second through hole formed in and extending through the second opposite connection pad and the second electric conduction structure is deposited and fixed in the second through hole;

wherein the first electric conduction structure and the second electric conduction structure are each formed of one of silver, aluminum, copper, tin, conductive carbon paste, conductive-particle-contained adhesive.

3. The power supply path structure as claimed in claim 1 , wherein the first connection section and the first opposite connection section of the first flexible circuit board each comprises a plurality of solder zones formed thereon for providing one of a connector and an electronic component to be soldered on the solder zones.

4. The power supply path structure as claimed in claim 1 , wherein the first flexible circuit board and the second flexible circuit board are each one of a single-sided board, a double-sided board, a multilayer board, and a rigid-flex board.

5. The power supply path structure as claimed in claim 1 , wherein the first electric conduction structure and the second electric conduction structure each has a top surface on which an insulation protection layer is formed.

6. The power supply path structure as claimed in claim 1 , further comprising a third power supply path structure formed on a bottom surface of the second flexible circuit board.

7. The power supply path structure as claimed in claim 1 , wherein the first extension section of the first flexible circuit board further comprises at least one pair of differential mode signal paths.