Research And Design Of High Speed Interface GTL Buffer

The frequency of GTL I/O Buffer is the bottleneck in the performance of the whole microprocessor, which is one of the most important units. The GTL I/O Buffer designed with the methodology of full custom can achieve high speed, high reliability and good compatibility, and it has great value in application and significant meaning in innovation.This thesis emphasizes on full custom design methodology of high performance GTL I/O Buffer. The GTL I/O Buffer is optimized at theory level, logic level, circuit level and layout level, and is implemented in 0.18μm CMOS process. Furthermore, the testing technique and packaging technology of the high speed interface is discussed. The result of test is that the frequency of the GTL I/O Buffer has arrived at 600MHz. This thesis mainly contributes to the following aspects:1. The theory of GTL interface technology has been researched, which is the solid foundation for research on high speed interface.2. Considering the characteristic of GTL input interface, the input interface is realized with two grade amplifiers. The result of test is that the input interface designed with this method has high frequency and resolving power.3. Considering the deficiency of traditional output interface, the method of auxiliary charge-up is proposed. The performance of GTL output interface designed with this method arrives at the advanced international level.4. The infection of process, voltage and temperature on the performance is considered adequately to improve the reliability. The result of simulation is that the designed GTL interface operates stably with the PVT variability.5. Considering the characteristic of higher frequency of GTL interface, the packaging mode of chip on board is proposed. The result of test is that this kind of packaging satisfies the request of design.6. Considering the characteristic of GTL interface, the method of testing is proposed which is suitable for the characteristic. The practical application reveals that the advantages of this method are convenience, shortcut, directness, accuracy and so on.