SIM Tech SIMCom SIM800C User Manual

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SIM800C_Hardware_Design_V1.00 19 2014-10-30
VBAT
MIN:3.0V
Figure 9: The minimal VBAT voltage requirement at VBAT drop
Note: Hardware power down voltage is 3.0V.
4.1.2. Monitoring Power Supply
AT command “AT+CBC” can be used to monitor the VBAT voltage. For detail, please refer to document [1].
4.2. Power on/down Scenarios
4.2.1. Power on SIM800C
Customer can power on SIM800C by pulling down the PWRKEY pin for at least 1 second and release. This pin
is already pulled up to VBAT in the module internal, so external pull up is not necessary. Reference circuit is
shown as below.
4.7K
47K
Turn on/off
impulse
PWRKEY
Power
on/down logic
R
VBAT
Module
1K
Figure 10: Powered on/down module using transistor
PWRKEY
Power
on/down logic
R
VBAT
Module
1K
Figure 11: Powered on/down module using button
The power on timing is illustrated as in the following figure.

SIM Tech SIMCom SIM800C Specifications

General

Brand	SIM Tech
Model	SIMCom SIM800C
Category	Control Unit
Language	English