Sim800 hardware design v1.05

Table Of Contents
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Figure 14: Reset circuit
The typical value of RESET pin high level is 2.8V, so for the 3V or 3.3V, customer could use MCU’s GPIO to
driver this pin directly, resistor in serial the RESET signal could enhance the ESD performance but the value
should not be too high, otherwise the level of RESET could be lower than threshold value; RESET hardware
parameters can refer to the following table.
Table 6: Electronic characteristic of the RESET Pin
Pin name Symbol Min Typ Max Unit
V
IH
2.7 2.8 2.9 V
V
IL
- - 0.6 V
RESET
T
pull down
105 - mS
The reset scenarios are illustrated in the following figures.
Figure 15: Reset timing sequence
SIM800_Hardware Design_V1.05 26 2014-03-25