1. solderability: plating gold solderability is equal to OSP pcb, while ENIG PCB is equal to HAL PCB, HAL solderability is the best among all surface finishing of PCB.
2 Gold Thickness, plating gold surface thickness is much thicker than ENIG PCB, but pad flatness is not as good as ENIG finishing.
3. Plating gold is normally suit for gold finger, some times also plating gold to solder pad.
PCB with ENIG surface
1. ENIG pcb surface is more yellow than plating gold PCB, clients may like the color of ENIG more.
2. ENIG Surface is easier to solder, won’t occur dewetting and untighten soldering.
3. There are only nickel and gold on PADS without soldermask open for ENIG pcb, signal transfer is only in copper line, won’t affect signal transfer quality.