Circuit board structure for mobile pci express module

A circuit board structure for mobile PCI express module applied to conform to PCI Express 4.0 specification, the circuit board structure for mobile PCI express module comprising:

• a top signal layer;
• a bottom signal layer, located on one side opposite to the top signal layer, wherein the top signal layer and the bottom signal layer comprising a core and a conductive copper wire respectively, the conductive copper wire being configured on the surface of the core for signal transmission;
• at least one power supply layer, configured between the top signal layer and the bottom signal layer;
• a plurality of first insulating layers, configured between the top signal layer and the power supply layer and configured between the bottom signal layer and the power supply layer;
• and
• a plurality of second insulating layers, configured between the power supply layer and the first insulating layers;
• wherein, the dielectric loss values of the first insulating layers and the second insulating layers are between 0.004 and 0.014 and the length of the conductive cooper wire is between 500 and 2500 mil, to reduce the signal loss of the mobile PCI express module less than 8 dB.