Table of Contents
Advertisement
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.
Module
TXD
RI
RXD
GND
Please visit vendors' websites to select a suitable RS-232 transceiver, such as: http://www.exar.com and
http://www.maximintegrated.com.
NOTES
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.
BC950N-N1_Hardware_Design
C1+
C1-
C2+
C2-
T1IN
T2IN
T3IN
T4IN
Level Shifter
T5IN
(1.8V~3.3V)
/R1OUT
R1OUT
R2OUT
R3OUT
Transceiver
Figure 21: Sketch Map for RS-232 Interface Match
V+
GND
VCC
3.3V
V-
T2OUT
T1OUT
T5OUT
T3OUT
T4OUT
R1IN
R2IN
R3IN
RS-232
LPWA Module Series
BC950N-N1 Hardware Design
GND
GND
GND
To PC Main Serial Port
1
6
2
7
3
8
4
9
5
GND
33 / 59
Advertisement
Table of Contents
