Neural Network Chips for Trigger Purposes in High Energy Physics

Two novel neural chips SAND (Simple Applicable Neural Device) and SIOP (Serial Input Operating Parallel) are described. Both are highly usable for hardware triggers in particle physics. The chips are optimized for a high input data rate at a very low cost basis. The performance of a single SAND chip is 200 MOPS due to four parallel 16 bit multipliers and 40 bit adders working in one clock cycle. The chip is able to implement feedforward neural networks, Kohonen feature maps and radial basis function networks. Four chips will be implemented on a PCI-board for simulation and on a VME board for trigger and onand off-line analysis. For small sized feedforward neural networks the bitserial neuro-chip SIOP may lead to even smaller latencies because each synaptic connection is implemented by its own bit serial multiplier and adder.