| As the increasing demand of portable products'batter power and the declining trends of batteries'size and weight brought by miniaturization of electronic products, the main problem is to improve cell's conversing efficiency in a DC-DC IC design.A high efficient and high integrated DC-DC converter has been designed to meet the application requirements of portable electronic product and the needs of energy saving. We use specific integrated circuit design method, the principle of BUCK DC/DC converter and the current mode PWM control technology.This paper is based on the research status and trends of switching power supply. Considering the improved efficiency, reliability, smaller chip area and ripple, the design specifications and optimal design are given. In addition, the converter's function modules are designed and the simulation results are given, such as bandgap reference circuit, overheat protection circuit, error amplifier, PWM comparator, oscillator generation circuit and bootstrap circuit design, etc.The simulation results show that the DC-DC converter could meet the design requirement of high efficiency. It can be widely used in notebook computers and I/O power supply, network system, digital set-top boxes, personal video recorders, flat-panel televisions and monitors, and distributed power systems.Each block and the whole system have been simulated using the Hspice simulation tools of Cadence. It covers the voltage range from 4.5V to 16V and provides the output voltage from 1.2V to 3.3V with a maximal output current of 3A. The simulation indicates that the power efficiency is above 90% with 12V supply voltage, 1.2V output voltage. The capacity of linear adjustment and load regulation is also pretty good. |
PDF Full Text Request