Rent’s rule

Off-Package Connections. The number of terminals needed to connect randomly a cluster of logic circuits (such as a chip or an MCP) to the rest of a system is predicted by a well-known empirical power law relationship known as Rent s rule ... 

Rent s rule can be applied at many levels of packaging, including chips, MCPs, cards, or boards. Values of 2.5 for A and 0.6 for p have been em-... 

The number of I/Os predicted by Rent s rule is often large for an MCP. However, Rent s rule assumes random interconnection to the rest of the system. Many systems can be partitioned into functional blocks (such as a microprocessor) that require significantly fewer interconnections to the rest of the system and, thus, break Rent s rule. This partitioning of the system into functional blocks containing a feasible number of chips is the first crucial decision in designing an MCP and often determines the number of chips and, thus, the size of the MCP. 

In the perimeter of the device 68 bond pads are arranged. Of these, 8 pads are needed for power and ground connections. Another empirical formula (Fier and Heikkila, 1982), based on Rent s rule, specifies that the number of I/O pads required to communicate effectively with the internal gates is given by... 

This relationship has popularly become known as Rent s rule based on the unpublished work by E.F. Rent at IBM. Although considerable research has been undertaken to disprove Rent s rule or to find architectures that overcome the pinout limitations, in many cases, there is a limitation on the amount of logic that can be associated with a given number of pins. This relationship severely affects the designs of some high-speed... 

The oil and gas lease under homestead law would simply be the right to conduct drilling operations on a person s surface property. The lease would not constitute a claim to minerals found under a particular surface area as under the rule of capture rule. Since the resci voir could be reached from different surface locations with slant drilling, the economic rent of a homestead lease would be far less than the value of a capture-rule lease. The difference in value would accrue to the driller-finder, thereby encouraging production by making drilling more efficient and profitable. 

However, there are some exceptions of this general rule s if strained systems are involved. Together with the synthetic goals, mechanisms will be discussed where syn fragmentation apparently is concur-rent or even preferred. ... 

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