DC/DC switch manostat is one of crucial parts in power source system, manostat must maintain constant tension, and can make quickly to inputting the change of the change of voltage and load current answer. Capacitance and inductance are the basiccest energy changeover parts of an apparatus in DC/DC, the charge pump that is based on capacitance and the DC/DC that are based on inductance have advantage and drawback each, have the land of use force.

Dimension of parts of an apparatus of charge pump DC/DC small, ply is thin, add EMI of this kind of structure interference is small, favor consequently in a lot of designs by the engineer. The SGM3110 of holy state microelectronics is a standard + the 5.0V output, DC/DC parts of an apparatus that is based on capacitance, if the system needs + the power source of 5.0V/100mA, can complete a design with very little PCB area expense, if the graph is shown 1 times,circuit is designed.

 

Graph 1: DC/DC of SGM3110 charge pump designs circuit.

 

As resemble element camera mobile telephone high increasing, flashlight becomes the key that designs success or failure. Traditional xenon lamp because the limitation of dimension of high pressure, physics and service life, cannot go in mobile phone midstream all the time. The development of technology of LED of high-power Bai Guang, make high-power white smooth LED flashlight more and more be approbated by the engineer, but the drive of this kind of flashlight, hot protection, delay is started, and the concussion of flashy big electric current to batteries, bring not small design challenge to the engineer again. The drive of SGM314X series flashlight that holy state microelectronics rolls out, use charge pump framework (graph 2) , drive electric current can amount to 500mA, 700mA, 1000mA, torch, photograph picture, glitter takes a picture 3 kinds of mode are OK and agile switch.

 

Graph 2: Circuit of drive of SGM314X series flashlight.

 

The smartphone gains ground increasingly, this kind of product handles demand of performance of speed, wireless communication to image and video, and the demand of LCD indication screen rises ceaselessly, bring about report of bad news of IC of much nucleus base band thereby bigger and bigger, batteries uses time to already made one of central points that consumer pays close attention to. The power source that consumer hopes to conveniently can be gotten charges for the mobile phone, power source of battery of solar battery, dry cell, lithium stands, the USB interface that nowhere is absent will lengthen use time to offer possibility for the mobile phone. The step up of SGM6600 synchronous commutate of holy state microelectronics DC/DC has the starting voltage of 0.9V, structure of efficient commutate of step up synchronism (graph 3) , can make an engineer easy face the design challenge that gets the sources of energy from solar battery and dry cell.

 

 

Graph 3: SGM6600 synchronous commutate rises profiling DC/DC circuit.

 

As the development of integrated circuit technology, hold IC of equipment base band compositive function is increasing, much voltage mixes a design to make the standard technology of SoC and SIP. Provide the DC/DC power source with a kind of on the safe side, appropriate cost for SoC and SIP product, become urgent matter. The problem such as sequential of report of increasingly complex load, fluctuation and laden protection is the challenge that the engineer must answer, POL and the power source concept of intermediate bus line are introduced in systematic design. The SGM6006 synchronous step-down that holy state microelectronics rolls out DC/DC, have the switch frequency of 1.4MHZ, the DC/DC when the special soft design that start can prevent fluctuation report produces load of high-pressured pulse attaint. In holding equipment to design, this parts of an apparatus is a good POL design product, the inductance that in designing circuit, uses is very small, whole DC/DC design takes up only very few PCB area, if the graph is shown 4 times,circuit is designed.

 

Graph 4: SGM6006 synchronous step-down DC/DC designs circuit.

 

Holy state microelectronics also rolled out the much DC/DC product of SGM2100 series, it introduced the idea of bus line of intermediate power source products plan. Of SGM2100 and SGM2101 advocate step up DC/DC becomes double section dry cell or lithium battery voltage + 5.0V controls (adjustable) bus line of the power source intermediate, high-power + bus line of 5.0V/2A power source can think result of frequency of USB interface, flashlight, high-power is put wait for laden power supply, can get in holding facility very big frequency power output and very strong flashlight are designed (graph 5) , if hold the need in equipment system to add small hard disk, the 3.3V/800mA step-down that small hard disk needs / step up power source can be obtained with low cost means from the bus line intermediate. (Limited company of microelectronics of state of emperor of chief inspector of Xu Qianjiang market)

 

Graph 5: The application of parts of an apparatus of SGM2100 series much DC/DC in holding equipment system.