Patent ID: 8681510

Claim:
A circuit board comprising: a first circuit area comprising a plurality of first electrical contacts; a first processing unit comprising a ball grid array (BGA) substrate, the BGA substrate having a plurality of solder balls, wherein the first processing unit is disposed on the first circuit area and is electrically connected to the first electrical contacts; a conductive pattern electrically connected to the first electrical contacts; a second circuit area comprising a plurality of second electrical contacts, wherein the second electrical contacts are electrically connected to the first electrical contacts; and a second processing unit disposed on the second circuit area and electrically connected to the second electrical contacts; wherein the BGA substrate further comprises a bypass circuit or a signal processing element, when the BGA substrate comprises the bypass circuit, the second processing unit is electrically connected to the bypass circuit via the second electrical contacts and the first electrical contacts, and a signal from the second processing unit is transmitted through the bypass circuit of the first processing unit, when the BGA substrate comprises the signal processing element, the second processing unit is electrically connected to the signal processing element via the second electrical contacts and the first electrical contacts, and the signal processing element is configured with the second processing unit.