A20唤醒电路设计参考
V1.0
2013-06-04
Version Date Changes compared to previous issue
V1.020130604
目录
1.概述 (4)
1.1.目的 (4)
1.2.适用范围 (4)
2.硬件电路设计 (4)
B插入唤醒 (4)
2.2.RTC唤醒电路设计 (5)
3.Declaration (6)
1.概述
1.1.目的
用于指导客户进行A20的唤醒电路设计。

1.2.适用范围
本文针对A20平台，因而非A20平台请不要参考该文档进行设计。

2.硬件电路设计
B插入唤醒
USB插入唤醒电路设计如图1所示：
图1USB插入唤醒电路
注意：USB插入唤醒电路中USB-WAKEUP的电压必须大于2.5V，AXP209才能正确的识别到此时有USB插入。

且USB-WAKEUP请接到到AXP209的GPIO1，不要随意更改。

2.2.RTC唤醒电路设计
RTC唤醒电路设计如图2所示：
图2RTC唤醒电路设计
注意：使用RTC唤醒时，二极管的上拉电源为AVCC，且将NMI#多拉一根线到AXP209的GPIO2，IO口请不要随意更改。

3.Declaration
This document is the original work and copyrighted property of Allwinner Technology (“Allwinner”).Reproduction in whole or in part must obtain the written approval of Allwinner and give clear acknowledgement to the copyright owner.
The information furnished by Allwinner is believed to be accurate and reliable.Allwinner reserves the right to make changes in circuit design and/or specifications at any time without notice.Allwinner does not assume any responsibility and liability for its use.Nor for any infringements of patents or other rights of the third parties which may result from its use.No license is granted by implication or otherwise under any patent or patent rights of Allwinner. This datasheet neither states nor implies warranty of any kind,including fitness for any
particular application.。