The Design And Implementation Of PROM Reading System With MTM Antifuse

The memory is a kind of semiconductor device which can store a large amount of binary numbers and program information in information technology.It is also the most representative device in the current semiconductor technology innovation which represents the economies of scale and advanced manufacturing process of the integrated circuit industry.One of all,the anti-fuse programmable ROM(PROM)has been having an extremely extensive application in the military affirms,security and aerospace such critical areas,because anti-fuse has a high reliability,excellent anti-interference and superior electronic characteristic.The main purpose of this paper is to design and implement the MTM anti-fuse PROM reading system.First,an in-depth research of the MTM anti-fuse was made,knowing that MTM anti-fuse has a lower and more concentrated on-resistance in comparison to ONO and gate oxide type anti-fuse,and the fine electronic properties of the MTM anti-fuse can be proved by ways of a theoretical model and a statistics of experimental data.Then,the composition of PROM reading system was discussed,which is mainly composed by address input detection module,pulse width extension module,sense amplifier and its controlling signals generation module,storage cell with MTM anti-fuse,and data lock-up module,and function implementation and timing analysis of each function module of PROM reading system were studied in this paper.Based on a comprehensive understanding of the working principle of the PROM reading system,it is determined that the main part of the reading time,which is one of the key performance indicators of the PROM reading system,is a sum of the pulse width of the narrow pulse from the address input detection module,pre-charge time,and dis-charge time by channel of storage cell.Next,the influences of the anti-fuse on-resistance on the performance of the reading system were discussed,and it is considered that a larger on-resistance will increase the reading time and the maximum resistance threshold,therefore it is essential to reach a trade-off on the both.Finally,the timing affairs of the PROM reading system were introduced,and the load on the bit-line of storage arrays was studied in detail,finding that the load on the bit-line is the worst case when all the storage cells that are not selected on the bit-line are on the programmed state.And on this basis,a large number of pre-simulation and post-simulation of the PROM reading system and its testing graphics were carried out,so it can be concluded that the simulation results are very convincing and reliable.The design of the PROM with a storage capacity of 256 Kbit was based on CSMC 0.5?m process,and used MTM anti-fuse as its programming component,and the physical layout of the PROM was fully customized adopting the bottom-up method.After passing the physical verification,a large number of post-simulation were carried out to verify the function and timing of the PROM reading system,and the final results shown that the PROM reading system in this project can function quickly and accurately,so the layout had been taped out and delivered to foundry.