SIM802 Hardware Design
3 Application interface
All hardware interfaces are described in detail in following chapters:
z
Power supply and charging control
(see Chapters 3.3 and 3.5)
z
Provide main serial interface and debug serial interface
z
Two analog audio interfaces
(see chapter 3.10)
z
SIM interface
(see chapter 3.11)
z
LCD interface
(see chapter 3.12)
z
GPIO interface
(see chapter 3.13)
z
ADC interface
(see chapter 3.14)
z
Buzzer interface
(see chapter 3.18)
3.1 SIM802 Pin description
Table 5: Pin description
Power supply
Pin Name
I/O
Description
DC characteristics
Comment
VBAT
Power
2 VBAT pins are dedicated to
connect the supply voltage.
The power supply of SIM802
has to be a single voltage
source of VBAT=
3.4V...4.5V. It must be able to
provide sufficient current in a
transmit burst which
typically rises to 2A.Mostly,
these 2 pins are voltage
input, however ,when use the
charge circuit to charge the
battery ,these pins become
the current output, select one
of these pins as the charge
current output Pin
Vmax= 4.5V
Vmin=3.4V
Vnorm=4.0V
VRTC
Power
Current input for RTC when
the battery is not supplied for
Vmax=2.0V
Vmin=1.2V
Do not keep pin
open, it should be
SIM802_HD_V2.01
12.01.2010
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