| This dissertation discusses significance and prospect of digital control integrated circuits based on current-mode techniques. First of all, various basic block circuits, such as current mirror, current conveyor, and current-switching circuit, to implement digital control circuit were introduced. Based on the theory of multiple-valued modulo-algebra and the theory of switch-signal, the grounded switch theory suitable to 12L circuits were established. On this basis, the circuits for realizing mod-3 arithmetic operations, such as addition, subtraction, multiplication and division, are designed at switch level. By using theory of switch-signal and the features of current-mode CMOS circuits, we proposes a mixed switch theory suitable to current-mode CMOS circuits. The design examples show that the theory can be used to design multiple-valued current-mode CMOS circuits well. The simulation and measured result for these designed circuits show that all proposed circuits realizing modulo-algebra operations have correct logic functions. Thus the effectiveness of the design theory at switch level is proved, while research on designing circuits of multiple-valued modulo-algebra systems were further enriched. The mathematics expressions describing CMOS multiple-valued D/A converter and relative circuits design are given by means of studying binary D/A converter, adopting a biasing current of the current mirror in order to increase the input current of the current mirror, decrease the switching delay and improved its functions. Based on experiments, the quatemary D/A converter with three thresholds and two thresholds are derived. respectively. Thus. both the information density of integrated circuits and speed of data processing are increased. Based on all researches above, this dissertation proposes the concrete circuit design of 8-bits digital control circuits. The sample chip is fabricated and its electric characteristics and typical applications are investigated.
|
PDF Full Text Request