| The electronic products are developed in the direction of multiple-function and high-performance. Thus the high-reliable power supply with large range voltage is demanded eagerly. In this case, the system requirements pose new challenges to the high performance design of multi-rail power integration. This dissertation mainly investigates the integration and management technology of the multi-rail power supply, and the new design is applied to the TFT-LCD driver system. The main work and the important achievements in this dissertation are listed as follows.1.The key techniques for multi-rail integrated power, taking TFT-LCD as an object of study, are analyzed. The new driving method and system structure of the TFT-LCD driver system, the requirements of TFT-LCD to the power supply, including multiple voltage rails and the large range voltage variation are arrived at.2.For the high-current integrated power technology, this paper studies the Boost DC-DC structure, analyzes the stability of the voltage loop and the current loop respectively, and linearizes the power stage using the state-space averaging method. The distribution of the Boost DC-DC pole-zero, and the compensation method are derived. In order to improve the capability of the power supply current output, an adaptive slope compensation method is presented. By using translinear circuit, to operate the current signal, eliminates the need for introducing the output voltage from an additional pin, achieves a dynamic slope compensation to solve the stability problem of the current loop, minimizes the negative impact to the carrying capacity of the system and the transient response.3.Considering lowing the power consumption, a low-voltage startup circuit is presented, which is used to take voltage from the output to provide power supply for the chip, quiescent current is small so reducing the need of load current from the power supply.4.In this paper, the control method of the charge pump by using the high-voltage integrated power of the charge pump as the gate driver voltage of TFT-LCD are analyzed. The adjustable output positive and negative charge pump are designed by using the method of linear regulated on-resistance of output transistor. In order to improve the offset effect under the high-voltage process, the elimination of offset of the switching bandgap reference is designed based on the theory of switched-capacitor in this paper. It eliminates the input offset voltage by using the auto-zero technology, and improves the accuracy of the output voltage which can be applied to variety of the circuits and low-power circuits that requires precise voltage reference in a certain period of time only when switching action happens.5.Aimed at the flicker phenomenon appearing as the gate of TFT-LCD is driven, the cause and the forming process of flicker are analyzed. A simple and practical high-voltage switch is presented whose falling time can be adjusted to improve the display effect obviously.6. In linear integrated power supply aspect, the LDO with the dynamic Miller compensated and high-performance op amp are designed.And op amp's slew rate up to 40V/us, bandwidth up to 20MHz, can be used for TFT-LCD of the linear system which is suitable as a common voltage and Gamma correction buffer.7.For the management to the integrated power supply of multi-rail output, the power start up sequence and the fault detection procedure are designed. Because of the probably injury to system from the inrush current and output voltage overshoot occurred easily during startup process of the power circuits, a design of digital soft-start circuit that is controlled by voltage and without external soft-start capacitor came out. The reliability of the overall circuit is enhanced since the total integration inside the chip and the reduction of demanding the external applied components.8.In order to solve the problems of some specification testing during the working mode, this paper designs the test mode that can simplify the test procedure, shorten the test time. The testing waveforms and results of the multi-rail integrated power are given in the end of this paper..
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