Design improvement of FPGA and CPU based digital circuit cards to solve timing issues

The digital circuit cards installed at NPPs (Nuclear Power Plant) are mostly composed of a CPU (Central Processing Unit) and a PLD (Programmable Logic Device; these include a FPGA (Field Programmable Gate Array) and a CPLD (Complex Programmable Logic Device)). This type of structure is typical and is maintained using digital circuit cards. There are no big problems with this device as a structure. In particular, signal delay causes a lot of problems when various IC (Integrated Circuit) and several circuit cards are connected to the BUS of the backplane in the BUS design. This paper suggests a structure to improve the BUS signal timing problems in a circuit card consisting of CPU and FPGA. Nowadays, as the structure of circuit cards has become complex and mass data at high speed is communicated through the BUS, data integrity is the most important issue. The conventional design does not consider delay and the synchronicity of signal and this causes many problems in data processing. In order to solve these problems, it is important to isolate the BUS controller from the CPU and maintain constancy of the signal delay by using a PLD