GSM/GPRS/NB-IoT Module Series
BC68&M66 Compatible Design
BC68&M66_Compatible_Design 19 / 31
4.5. Network Status Indication
The NETLIGHT pin can be used to drive a network status indicator LED. A reference design is shown
below.
4.7K
47K
VBAT
2.2K
BC68/M66 Module
NETLIGHT
Figure 10: Reference Circuit of NETLIGHT
4.6. (U)SIM Interface
M66 supports 1.8V or 3.0V SIM/USIM cards, while BC68 supports 1.8V or 3.0V USIM cards. The pin
assignment of BC68
’s USIM interface and M66’s (U)SIM interface is compatible.
The following figure shows a reference design for (U)SIM interface with a 6-pin (U)SIM card connector.
22R
22R
22R
100nF
(U)SIM Card Connector
GND
ESD
33pF
33pF
33pF
VCC
RST
CLK
IO
VPP
GND
GND
15K
SIM_VDD
SIM_GND
BC68/M66 Module
SIM_VDD
SIM_RST
SIM_CLK
SIM_DATA
Figure 11: Reference Circuit of (U)SIM Card Interface with a 6-Pin (U)SIM Card Connector
