Today,Membrane switchPower supply technology four big trends: power supply technology has always been one of the most important technology in electronic circuit research, and switching power supply technology, and the main technology in the power supply technology.Turn the following pick this technical article, can explain well the switch power supply technology in some of the new progress in recent years.
A, not isolated DC/DC technology rapid development
In recent years, the isolated DC/DC technology is developing rapidly.At present due to load a set of electronic devices and electronic systems, would require the power supply system to provide multiple voltage level.Such as desktop PC machine requires a + 12 V, + 5 V and + 3.3 V, 12 V four and standby + 5 V voltage, voltage on the motherboard requires 2.5 V, 1.8 V, 1.5 V, and even 1 V, etc.A could not give so much in AC/DC voltage output, and most of the low voltage power supply current is very big, therefore has developed a lot of the isolated DC/DC, they basically can be divided into two broad categories.Internally contains power switch device, named DC/DC converters.Another does not contain the power switch, need external power MOSFET, said the DC/DC controller.According to the circuit function division, a step-down STEP - DOWN, STEP up the BOOST, and can lift pressure BUCK - BOOST or SEPIC, etc., and positive pressure to suction of INVERTOR etc.Among them most varieties, the fastest growing or step-down STEP - DOWN.According to the size of the output current, is divided into single phase and two phase and heterogeneous.Is given priority to with PWM control mode, a small number of PFM.
In the isolated DC/DC conversion technology of TI company's preliminary inspection gate drive technology using digital technology to control the synchronous BUCK, adopting the technique of DC/DC conversion efficiency up to 97%, which is its representative products such as TPS40071.Methods have appeared in the BOOST booster MOSFET instead of the diode synchronous BOOST products.In the field of low pressure, increase the efficiency of the amplitude is very big, and is trying to further eliminate body diode conduction of MOSFET and reverse recovery problem.
Second,Membrane switchBlowing digital horns of switch power supply
At present in the electronic analog circuit system, TV, audio, picture processing, communication, network and so on are gradually realize the digitization, and the last one is not digital fortress is the power source.In recent years, the research trend of digital power supply, also more and more.In the aspect of power supply digital walk in front of the company have TI and Microchip.TI company DSP has both advantages and acquired a professional manufacturer of PWM IC UNITRODE company, the company has made the communication with 48 v output TMS320C28F10 high-power power supply module, which is suitable for digital control and PWM PFC part completely.Now, the TI company have developed many digital PWM control chip.At present mainly UCD7000 series, the series of UCD8000 and UCD9000 series, they will become the next generation of digital power pathfinder.They generally includes hardware and software programming to do.Logic part of the hardware part includes PWM, clock, amplifier circuit of adc, analog-to-digital conversion and digital processing, and actuation, detection and treatment of the synchronous rectifier etc.