Shanghai MXCHIP Information Technology Co. Ltd. EMW3239 Benutzerhandbuch
Application Note
[Page 8]
Design Considerations of EMW3239
Relative contents of the module are sent by pin UART2_TX. Mobile phone could connect to internet and
have normal communication with app at NORMAL WORK. Module must in ATE mode when certificate with
SRRC, FCC, CE. MFG mode could be used in product storage test. Module must in BOOTLOADER mode when
update firmware by UART.
Reset pin
Pin 13 is reset pin triggered by low level voltage. Voltage must over 2.9V. Pin should be in dangling state
when it is not working. There is weak pull-up resistor inside. Please make sure the pin is in high level voltage
when the module is powered on.
SPI
Pin 4~7could be used as off-chip SPI port. Maximum transport rate could be 25Mbps with host and slave
mode, duplex mode and simplex mode.
I2C
Standard mode (100kbps), fast mode (400 kbps), high speed mode (1Mbps) is supported in I2C.
SWDIO/SWCLK
Standard mode (100kbps), fast mode (400 kbps), high speed mode (1Mbps) is supported in I2C.
SWDIO/SWCLK
Module supports with one standard SED port without external pull-up or pull-down resistance. Pin 25 and
Pin 26 supports with online debugging and upgrading with J-FLASH or used as GPIO.
GPIO
EMW3239 has 25group of GPIO that could be reused as other pins.
UART
Module has one current control UART communications and one normal UART communication. Pin 29
and Pin 30 are used as serial port of users (Test information, download and communication). Pin 8 and Pin 12
is debugging ports (running log print). Please make sure Wi-Fi RX and TX is connected to host RX and TX.
VBAT
VBAT
VBAT supports for RTC,PIN10 is clock source which requires power supply 3.3V. External output
compensation calibration in 512HZ could be used in RTC. RTC has programmable alarm and programmable
period interruption wake-up from stop mode to standby mode.
Power supply of EMW3239 is from 2.6V to 3.6V. Low voltage working mode is from 2.6V to 3.0V with
battery. Common working mode is from 3.0V to 3.6V. Rated power is only used as pressure test parameter.
Permanent damage would be caused if the device works in this condition.
Others
Pin floating is not allowed in EMW3239. Pin39 and pin 40 is power supply input that could be added a
10uF ceramic capacitors closing to two pins. Power supply is 2.6V to 3.6V. Module could be breakdown if
the voltage is over 3.6V.
Typical PCB design is shown in figure 2.6.
In order to make sure the antenna performance, sufficient clearance zone should be designed in the
antenna part. PCB part below antenna could be hollowed up. Copper, route, closing to metal element is not
allowed if the structure needed. P1 to P8 should connect to ground with copper.