LPWA Module Series
BC950N-N1 Hardware Design
The following circuit shows a reference design for the communication between the module and a PC with
standard RS-232 interface. Please make sure the I/O voltage of level shifter which connects to module is
3.0V.
TXD
RXD
RI
Module
GND
C1+
C1-
C2+
C2-
V+
VCC
GND
V-
3.3V
T1IN
T2IN
T3IN
T4IN
R1IN
R2IN
R3IN
R1OUT
R2OUT
R3OUT
T1OUT
T2OUT
T5OUT
T3OUT
T4OUT
T5IN
GND
GND
/R1OUT
1
2
3
4
5
7
8
9
GND
To PC Main Serial Port
GND
RS-232
Transceiver
6
Level Shifter
(1.8V~3.3V)
Figure 21: Sketch Map for RS-232 Interface Match
Please visit vendors’ websites to select a suitable RS-232 transceiver, such as: http://www.exar.com and
http://www.maximintegrated.com.
1. Transistor circuit solution is not suitable for applications with high baud rates exceeding 460Kbps.
2. “
” represents the test point of UART interfaces. It is also recommended to reserve the test points of
VBAT and PWRKEY, for convenient firmware upgrade and debugging when necessary.
3. “*” means under development.
3.9. USIM Interface
The module provides a USIM interface compliant to ISO/IEC 7816-3, enabling the module to access to an
external 1.8V/3.0V USIM card.
NOTES
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