Slot design for flexible and expandable system architecture
An apparatus includes a printed circuit board including a connector footprint comprising a first footprint portion operative to receive a first connector portion and a second footprint portion operative to receive a second connector portion. The first footprint portion is compliant with a first communications link type and the first and second footprint portions are jointly compliant with a second communications link type. The printed circuit board includes first conductive traces coupled to the first footprint portion and a first device footprint. The first conductive traces are selectively configurable according to a selected one of the first and second communications link types. The printed circuit board includes a second conductive traces coupled to the second footprint portion and the first device footprint. In at least one embodiment of the apparatus, the first communications link type is AC-coupled and the second communications link type is DC-coupled.
1. An apparatus comprising:
a printed circuit board comprising:
a pattern of electrical contacts on a first surface of the printed circuit board, the pattern comprising a first portion and a second portion, the first portion being operative to receive a first connector portion and the second portion being operative to receive a second connector portion, the first portion being compliant with a first communications link type and the first and second portions being jointly compliant with a second communications link type;
first conductive traces coupled to the first portion and a first device footprint, the first conductive traces being selectively configurable according to a selected one of the first and second communications link types; and
second conductive traces coupled to the second portion and the first device footprint; and
a connector coupled to the pattern, the connector comprising a first connector portion and a second connector portion, the connector being capable of coupling, according to the first communications link type, the first connector portion to a first device having a first number of terminals and capable of coupling, according to the second communications link type, the first connector portion and the second connector portion to a second device having a second number of terminals, the first number of terminals being less than the second number of terminals.
2. The apparatus, as recited in claim 1 , wherein the first communications link type is AC-coupled and the second communications link type is DC-coupled.
3. The apparatus, as recited in claim 1 , wherein the first conductive traces are configured to AC couple the first portion and the first device footprint and the second conductive traces are floating.
4. The apparatus, as recited in claim 1 , further comprising a first switch coupled to first and second connection points of an individual trace of the first conductive traces.
5. The apparatus, as recited in claim 4 , further comprising one of a zero Ohm resistor, jumper, wire, and a capacitor coupled to the first and second connection points.
6. The apparatus, as recited in claim 4 , further comprising a second switch coupled in series with a capacitor, the second switch and the capacitor being coupled in parallel to the first switch and coupled to the first and second connection points.
7. The apparatus, as recited in claim 1 , further comprising:
a processor connected to the connector.
8. The apparatus, as recited in claim 1 , further comprising:
a peripheral device connected to the connector.
9. The apparatus, as recited in claim 1 , wherein the first device footprint is capable of receiving a processor including a first interface of the first communications link type and a second interface of the second communications link type.
10. The apparatus, as recited in claim 1 , wherein the first communications link type is Peripheral Component Interconnect Express (PCIE) and the second communications link type is HyperTransport (HT).
11. The apparatus, as recited in claim 1 , wherein a communications link of the first communications link type and a communications link of the second communications link type are both serial bus communication links.
12. The apparatus, as recited in claim 1 , wherein the first communications link type is associated with a first number of signals and the second communications link type is associated with a second number of signals, the first number of signals being less than the second number of signals.
13. An expansion slot of a printed circuit board assembly comprising:
a connector means capable of coupling, according to a first communications link type to a first device having a first number of terminals and capable of coupling, according to a second communications link type to a second device having a second number of terminals, the first number of terminals being less than the second number of terminals;
means for coupling the connector means to a device, the means for coupling being selectively configurable according to a selected one of the first communications link type and the second communications link type, a first set of lanes being used for the first communications link type and the first set of lanes and a second set of lanes being jointly used for the second communications link type.
14. The expansion slot, as recited in claim 13 , wherein the first communications link type is AC-coupled and the second communications link type is DC-coupled.