Huawei Technologies Co. Ltd UM01-HW 用户手册
MC703 CDMA EV-DO Wireless Module V100R001
Product Description
Issue 1.00 (2009-9-10)
Huawei Proprietary and Confidential
Page 22 of 40
Figure 3-2 Normal power-off process of the UM01-HW UMTS module
3.8V
t>0.5s
2.6V
1.8V
VBAT
TERM_ON
VREG_MSMP
RESET_N
MODULE OFF PROCESS
OFF
2.6V
2.6V
GPIOs
t
off
t
reset1
MODULE STATE
RUN
When the RESET_N pin is driven low for 100 ms, the UM01-HW UMTS module can be reset.
Figure 3-3 shows the reset process of the UM01-HW UMTS module.
Figure 3-3 shows the reset process of the UM01-HW UMTS module.
Figure 3-3 Reset process of the UM01-HW UMTS module
Note: The RESET_N pin is sensitive to interference. Therefore, the lines on the interface
board of the UM01-HW UMTS module should be not longer than 2 cm. Otherwise, the
UM01-HW UMTS module may be reset because of interference.
board of the UM01-HW UMTS module should be not longer than 2 cm. Otherwise, the
UM01-HW UMTS module may be reset because of interference.
3.5.4 RTC Power Supply
The power supply pin for the real-time clock (RTC) can obtain current from the VBAT pin
through software enabling to charge the backup battery of the RTC. The power supply input is
monitored by a CPU.
through software enabling to charge the backup battery of the RTC. The power supply input is
monitored by a CPU.
The UM01-HW UMTS module defines the VCOIN pin for the input of the backup power
supply on the 60-pin B2B connector to implement the power supply input for the RTC.
supply on the 60-pin B2B connector to implement the power supply input for the RTC.