EXCLUSIVE-OR cell for neural network and the like

In a neural network, a synapse cell useful in performing pattern recognition tasks comprising:

• a pair of input lines for receiving a differential input vector value;
• a pair of output lines for providing a difference current;
• and
• first, second, third and fourth floating gate devices, said first and said second floating gate devices having their gates coupled to one of said input lines and their drains coupled to alternate ones of said output lines, said third and fourth floating gate devices having their gates coupled to another of said input lines and their drains also coupled to alternate ones of said output lines,
• said floating gate devices storing a weight such that said difference current provided across said pair of output lines is proportional to the match between said input vector and said weight.

In a neural network, a synapse cell for generating an analog current related to the binary dot product of an input vector and a weight, said cell comprising:

• first and second input lines providing said input vector and its complement, respectively;
• a pair of output lines providing said analog current:
• a pair of floating gate devices each having their gates coupled to said first line, their drains coupled to alternate ones of said output lines, and their sources grounded;
• another pair of floating gate devices each having their gates coupled to said second input line, their drains coupled to alternate ones of said output lines and their sources grounded,
• each of said floating gate devices also having a floating gate for storing said weight such that said analog current difference is related to the match between said weight and said input vector.