基于SiC414設(shè)計(jì)的6A降壓電源穩(wěn)壓技術(shù)
SiC414集成了5V/200mA LDO的6A降壓電源穩(wěn)壓器,開關(guān)頻率高達(dá)1MHz,全部采用陶瓷電容.連續(xù)輸出電流達(dá)6A,效率大于95%,內(nèi)部軟起動(dòng)和軟關(guān)斷,主要用在筆記本電腦,臺(tái)式電腦和服務(wù)器,數(shù)字HDTV和消費(fèi)類電子,網(wǎng)絡(luò)和通信設(shè)備,打印機(jī),DSL和STB,嵌入式應(yīng)用和點(diǎn)負(fù)載電源.本文介紹了SiC414主要特性, 功能方框圖, 典型應(yīng)用電路圖和SiC414評(píng)估板電路圖以及材料清單(BOM).
The Vishay Siliconix SiC414 is an advanced stand-alone synchronous buck regulator featuring integrated power MOSFETs, bootstrap diode, and an internal 5 V LDO in a space-saving MLPQ 4 x 4 - 28 pin package.
The SiC414 is capable of operating with all ceramic solutions and switching frequencies up to 1 MHz. The programmable frequency, synchronous operation and selectable power-save allow operation at high efficiency across the full range of load current. The internal LDO may be used to supply 5 V for the gate drive circuits or it may be bypassed with an external 5 V for optimum efficiency and used to drive external n-channel MOSFETs or other loads. Additional features include cycle-by-cycle current limit, voltage softstart, under-voltage protection, programmable over-current protection, soft shutdown and selectable power-save. The Vishay Siliconix SiC414 also provides an enable input and a power good output.
SiC414主要特性:
• High efficiency > 95 %
• 6 A continuous output current capability
• Integrated bootstrap switch
• Integrated 5 V/200 mA LDO with bypass logic
• Temperature compensated current limit
• Pseudo fixed-frequency adaptive on-time control
• All ceramic solution enabled
• Programmable input UVLO threshold
• Independent enable pin for switcher and LDO
• Selectable ultra-sonic power-save mode
• Internal soft-start and soft-shutdown
• 1 % internal reference voltage
• Power good output and over voltage protection
• Halogen-free according to IEC 61249-2-21 definition
• Compliant to RoHS directive 2002/95/EC
SiC414應(yīng)用:
• Notebook, desktop and server computers
• Digital HDTV and digital consumer applications
• Networking and telecommunication equipment
• Printers, DSL and STB applications
• Embedded applications
• Point of load power supplies
圖1.SiC414功能方框圖
圖2.SiC414典型應(yīng)用電路圖[!--empirenews.page--]
圖3.SiC414評(píng)估板電路圖
SiC414評(píng)估板材料清單(BOM):
圖4.SiC414評(píng)估板PCB布局圖(頂層)