In-system programmable logic device with four dedicated terminals

摘要: An in-system programmable logic device is disclosed which may be configured or reconfigured while installed in a user's system. The employs non-volatile memory cells such as floating gate transistors the elements, and hence retain particular programmed configuration virtually indefinitely during powered-down state. operable normal state several utility states for reconfiguring device. controlled by an internal machine executes equations whose variables are levels driving two dedicated pins present One pin receives serial input data loads shift register latch. contents of latch employed to select row level selected programmed. inputs outputs isolated from states, so that system does not affect operation states. A voltage multiplier circuit included generate high necessary program supply voltage, thereby further conserving on required number pins. By programming cell, user either latched condition tri-stated condition.