单片机有的是用1AA或2AA 电池供电的,这时为了保正单片机的工作电压在2.5~5.0之间,这时就要用到DC-DC升压电路了,升压电路一般要用到电感 和肖特基二极管 电阻 电容等外围元件,空间较小的情部一下就要想办法精简一下外围器件了,这时不需电感和肖特基的只要一下芯片接上电就能升压当然电最理想的,当是理想一般都不太现实,生产这种内置电感和肖特基的公司在前几年在美国有一家有做,后来公司被收购了。这种芯片不但是很贵交货期也长,成本才是“王道”的今天,只有折中了,外置电感不用外置肖特基二极管的同步升压电路是首选了。国产的同步升压电路有很多,这里有款PT1311的可调节输出电压的同步DC-DC升压电路可以参考一下。
主要特点:
FEATURES
High Efficiency: Up to 93%
Very Low Quiescent Current: Only 25μA During Operation
600mA Output Current
0.85V to 4.2V Input Voltage Range
1.2MHz Constant Frequency Operation
No Schottky Diode Required
Anti-ringing Control Minimizes EMI
Output Short Protect
Shutdown Mode Draws≤1μA Supply Current
Current Mode Operation for Excellent Line and Load Transient Response
Over temperature Protected
Feedback Voltage Auto Detect
SOT23-6 Package
APPLICATIONS
Li-ion Battery Chargers
USB Audio Devices
Wireless Mice
Digital Still Cameras
MP3/MP4 Players
Portable Instruments
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