Skjerven Morrill MacPherson LLP
Protection of logic modules in a field programmable gate array during antifuse programming
 To protect logic module output devices from high voltages, logic modules are not powered during antifuse programming. In some embodiments, two separate power input terminals VCC1 and VCC2 are provided: power input terminal VCC1 being coupled to power the logic modules, and power input terminal VCC2 being coupled to power the programming control circuitry. Power terminal VCC1 is left floating or is grounded during antifuse programming such that the logic modules are not powered but such that the programming circuitry is powered during antifuse programming via the second power terminal VCC2. Logic module output protection transistors are not required nor is the associated charge pump. Because the logic module input devices are not powered, a current surge through the input devices on power up does not occur and an internal disable signal and associated circuitry is not required. In one embodiment, the field programmable gate array is made smaller because it has no internal disable signal and associated circuitry, no logic module output protection transistors, and no charge pump that operates during normal circuit operation. In embodiments, power input terminal VCC2 is a high voltage compatible power input terminal. 
QuickLogic Corporation
H H
H01L H01L
inventional inventional
Sudarshan Paige A. David D.
Varshney Kolze Eaton