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The RAM SO-DIMMs are required to be PC100 compliant. The PC100 SDRAM specification, revision 1.63, is available from Intel's website at
http://developer.intel.com/design/chipsets/memory/sdram.htm#S1
The electrical characteristics of the RAM SO-DIMM are given in section 4.5.6 of the JEDEC Standard 21-C, release 7. The specification is available from the Electronics Industry Association's web site, at
http://www.jedec.org/download/default.htm
The JEDEC and PC100 specifications define several attributes of the DIMM, including storage capacity and configuration, connector pin assignments, and electrical loading. The specifications support SO-DIMMs with either one or two banks of memory.
The JEDEC specification for the SO-DIMM defines a Serial Presence Detect (SPD) feature that contains the attributes of the module. SO-DIMMs for use in the PowerBook computers are required to have the SPD feature. Information about the required values to be stored in the presence detect EEPROM is in section 4.1.2.5 and Figure 4.5.6-C (144 Pin SDRAM SO-DIMM, PD INFORMATION) of the JEDEC standard 21-C specification, release 7.
Capacitance of the data lines must be kept to a minimum. Individual DRAM devices should have a pin capacitance of not more than 5 pF on each data pin.