MeiG
Product
Manual
of
SLM750
Module
SLM750
Module
Hardware
Design
Page 44, total 84 pages
The module USB_VBUS is not used to power the module, but is used to detect the insertion
and pull-out of the USB.
In order to reduce the signal interference of USB high speed data transmission, connect R1 and
R2 between USB_DM and USB_DP interface circuit to improve the data transmission rate. It is
recommended that you use R1 and R2 of 0
Ω
.
In order to improve the antistatic performance of USB interface, it is recommended to add ESD
protection components on USB_DP and USB_DM interface circuit. It is recommended that you
use ESD components with junction capacitance less than 2pF.
In order to ensure that the USB is reliable, consider more about the protection of USB when
designing, such as the protection of USB on Layout requires impedance control of 90
Ω
for
USB_DP, USB_DM, tracing strictly according to differential requirements, and keeping away
from the interference signal as far as possible.
Do not trace the USB line in the crystal oscillator, oscillator, magnetic device and RF signal; it
is recommended to trace inner differential line and up and down around the package.
3.10.3 USB driver
SLM750 supports various operation systems, such as PC operation systems: Windows 10,
Windows 7/8,embedded operation system, Linux2.6 or higher, Android
2.3/4.0/4.2/4.4/5.0/5.1/6.0/7.0, which requires private USB driver support.
For different operating systems and different VID and PID, USB driver provides different
driver files. Contact supporting staff if you have specific requirements.
3.11 UART Interface
SLM750 provides two UART interfaces: main UART interface and debug UART interface.
The features of them are illustrated as below:
Main UART interface supports 9600, 19200, 38400, 57600, 115200, 230400, 460800,
921600bps and 30000000bps baud rate, the default is 115200bps. The interface can be used
for data transmission and AT command communication.