SimCom SIM800C User Manual

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SIM800C_Hardware_Design_V1.02 27 2015-4-27
VDD_EXT
4.7K
47K
UART1_TXD
4.7K
Module
VDD_EXT
RXD
VDD
DTE
Figure 21: TX level matching circuit
VDD_EXT
4.7K
47K
4.7K
DTE
UART1_RXD
M odule
VDD_EXT
TXD
VDD
Figure 22: RX level matching circuit
4.5.3 Debug Interface
SIM800C could achieve software debug function through USB interface. When powering on the module,
connect USB_VBUS, USB_DP, USB_DN, and GND to PC, then install the driver following the prompts, a
UART port could be recognized by PC, customer could achieve the software Debug with this UART port.
SIMCom recommended the following connected diagram:
MODULE
USB
USB_DP
USB _ DN
USB _ DN
GND
GND
22R
USB _ DP
USB_VBUS
VBUS
22 R
1uF
Figure 23: USB reference circuit
The TVS on USB data line should be less than 5pF, and traced by differential forms.
Note: please reserve the USB interface or test point for the further debugging
Table 10: USB_VBUS operation voltage

SimCom SIM800C Specifications

General

Brand	SimCom
Model	SIM800C
Category	Control Unit
Language	English