| In this paper, a voltage-loop PSM/PWM Boost DC-DC power management IC chip was designed and analyzed. The models are based on Chartered 0.35μm Techonolgy. Cadence software was used for simulation. Simulation results showed that the switch frequency is about 400KHz, the advisable temperature is from -40℃～125℃, the efficiency coefficient reaches to above 90% at the normal load, the total power dissipation is less than 0.16mW, the output voltage error is in±1%, and these results satisfy the industry requirements perfectly.Based on the problems of research, the paper presents the modulating method and controlling method of the DC-DC converter IC firstly, and then gives a minute explanation of the system frame and principle of the voltage-loop PSM/PWM Boost DC-DC converter IC.In the fourth chapter, those modules in the IC chip were introduced and designed in detail, including designing the mode conversion circuit and pulse detector, As the different pulse width, The controller could change the mode between PWM and PSM, the mechanism could make the efficiency coefficient above 90% among a wide-load range; designing an adjustable output voltage reference with low offset, low power consumption and high PSRR; designing a comparator with high precision; and designing error-amplifier and compensation circuit, comparator, low-voltage control circuit, saw-tooth generator circuit, low-voltage safeguard circuit, PSM controller and so on.All these sub-circuits were designed and simulated with Cadence. The simulations results shown these circuits were designed correctly.The simulation results of the whole circuit were recorded in the fifth chapter. We can see that the chip achieves its function correctly through the simulation results. The sixth chapter summarizes the paper and gives some further suggestions.
|
PDF Full Text Request