The challenge that a variety of DC-DC technology join forces should design to power source (2)
[introduction] the challenge that in an article “ a variety of DC-DC technology join forces answer power source to design (one) in ” , we introduced switch the improvement that develop attacks mixes type converter how to improve light laden condition. In the article, we enclose the introduction the promotion of technology and new material to power source efficiency.
Enclose a technology newly to help design personnel increase power density
Another kind of kind that raises power density is the PCB area that reduces place to need. Among them a kind of method is package union arrives in DC/DC module. The MicroSiP that Texas Instruments offers and module of MicroSiL power source, compositive in power source converter passive component and integrated circuit (IC) , embed IC on FR4 lamination substrate, install inductor on base material, make individual equipment with this.
Module of completely compositive MicroSiP power source mixes IC passive component is compositive in the equipment to a highest and compositive level. The smallest module uses BGA to enclose a form, its occupy an area to be not worth 7mm² .

Graph 1: MicroSiP is enclosed embed integrated circuit in substrate, be in passive component caboodle coping, in order to comprise miniature DC-DC converter (data sources: Texas Instruments)
MicroSiL equipment is compositive inductor and adjuster IC, used exterior capacitor. Of this module bring crural allocation and outline to be similar to QFN to enclose. For example, module of TPS82085 power source is synchronous step-down converter, can the 8 makes a foot enclose transmission 3A electricity from 3mm×2.8mm.
Compositive and OK reduce yuan of parts of an apparatus considerably occupy an area, but need balance advantages and disadvantages. For example, microSiP encloses in controller above put inductor, get on package installation in PCB. Design photograph comparing with schism, these characteristic metropolises raise the height of MicroSiP module.
Should as far as possible cut occupy an area, still need to reduce the size of inductor. Coil inductance and its area and pen number become direct ratio, was thought not to change inductance, reduce an area, increase use wire with respect to need, but also can cause the DC resistance that increases coil at the same time.
Surmount the design of silicon: SiC and GaN parts of an apparatus
To go after higher performance, design personnel begins to explore the other data besides silicon. The electron that makes with SiC and GaN yuan parts of an apparatus begins to replace silicon parts of an apparatus in a few electric power application, both belongs to a broadband before unoccupied place (WBG) semiconductor.
What we consider back and forth first is solid the belt is unoccupied place, the belt of solid is unoccupied place with Yu Heng volume price takes the energy between coping and conduction band bottom to differ (EV) , it is the main factor of certain material conductivity.
The belt of silicon is unoccupied place for 1.1eV, under photograph comparing, the belt of WBG semiconductor is unoccupied place it is 3.3V respectively (SiC) with 3.4V (GaN) , accordingly, need more energy to transmit the electron conduction band from price band. This has an advantage quite to power semiconductor: Compare with silicon photograph, WBG parts of an apparatus is had lower guide electrify block, taller puncture restores character voltage, outstandingly reversely, and can be below taller switch frequency work.
Taller switch frequency allows to use smaller capacitor, inductor and transformer, its dimension, weight and cost are saved greatly. In the meantime, DC-DC changeover efficiency is OK and highest promotion 10% .
Texas Instruments released a LMG5200 recently, WBG semiconductor and advanced enclosed union to be in one case. LMG5200 is level of half bridge power, enclose in a QFN in compositive the effect of GaN power field of two 80V is in charge of (FET) with driver of a high frequency GaN. LMG5200 will with existing product (like TPS53632) conjugate is used, service at all sorts of application, the synchronous step-down converter that includes to be used at computation, industry and telecommunication application and 48V POL converter.
Summary
The efficiency that promotes electric power changeover solution and power density need use the method with much integrated discipline, draw lessons from controller design, enclose and the professional knowledge of semiconductor research respect. Have market only the strong point of each domain, design personnel ability satisfies the requirement of numerous application, these application can apparel from the low power comsumption of batteries drive equipment and portable equipment, wait to the telegraphic switching equipment of high power and data center, range is very wide.
The article is reprinted oneself trade lustre electron.