A module standard for integrated circuit such as FPGAs is provided in which power
supply voltages for daughtercards are not fixed in advance. Instead programmable
power supplies are provided and a method is provided in which each daughtercard
can specify the required power supply voltage. Thus, unlike prior-art systems,
this modular system is backward and forward compatible with chips, such as FPGAs,
from many process generations allowing easy upgrading as new FPGA families become
available. A motherboard or baseboard for use with this invention includes a plurality
of module connectors into which compatible modules or "daughtercards" can be plugged
and a plurality of programmable power supplies. In a preferred embodiment there
are four sets of module connectors and sixteen programmable power supplies. This
allows each module to have four independently specifiable power supply voltages.
A module may also connect several power supplies together in order to obtain higher
current at a single voltage. Various schemes are described to ensure that the programmable
power supplies will never deliver too high a voltage to the components on the modules.
