Patent ID: 7688112

Claim:
A method of providing anti-SEE protection of high speed data processing paths in a cell of a CML integrated circuit comprising: converting a SEE induced collector current pulse in a HBT of the cell to a low voltage level by use of a collector loading resistor connected to a collector node of the HBT; hard limiting a voltage of the collector node of the HBT to a level that is lower than a lowest logic voltage in the collector node during undisturbed operation of the cell and that is still sufficiently high to prevent an unrecoverable disturbance of other nodes of the cell due to a SEE; providing a low-impedance path for a SEE-induced current pulse in a base node of the HBT of the cell in order to limit a voltage of the base node to a level that is lower than a lowest logic voltage in the base node during the undisturbed operation of the cell and that is still sufficiently high to prevent an unrecoverable disturbance of the other nodes of the cell; wherein the HBT modified by application of the above techniques for converting the collector current pulse, hard limiting the collector voltage, and providing a low-impedance path represents a modified switching component; wherein the base, collector, and emitter nodes of the HBT represent the respective base, collector and emitter nodes of the switching component, while a loading resistor node not connected to the HBT's collector node represents a resistor node of the switching component; adding one additional input for each main input of the cell so that the corresponding main and additional inputs receive two independent but logically and electrically equivalent signals; combining the corresponding main and additional inputs of the cell by use of a logic function utilizing two switching components, wherein the first switching component has its base node connected to the main input of the cell and the second switching component has its base node connected to the additional input of the cell, and wherein the logic function comprises one of an OR function and a NOR function.