Usim Interface - Quectel BC66 Hardware Design

Table 10: Pin Definition of SPI Interface
Pin Name Pin No.
SPI_MISO 3
SPI_MOSI 4
SPI_SCLK 5
SPI_CS 6
The module provides a 1.8V SPI interface. A level translator between the module and host should be
used if the application is equipped with a 3.3V processor or device interface. A voltage level translator that
supports SPI data rate is recommended. The following figure shows a reference design.
Module
VDD_EXT
CS_SPI
SCLK_SPI
MISO_SPI
MOSI_SPI
Figure 20: SPI Interface Reference Circuit with Translator Chip

3.10. USIM Interface

The module provides a USIM interface compliant to ISO/IEC 7816-3, enabling the module to access to an
external 1.8V USIM card.
The external USIM card is powered by an internal regulator in the module and supports 1.8V power
supply.
BC66_Hardware_Design
I/O Description
DI Master input slave output of SPI interface
DO Master output slave input of SPI interface
DO Clock signal of SPI interface
DO Chip select of SPI interface
VCCA
0.1uF
OE
A1
A2
A3
A4
VCCB
0.1uF
GND
B1
Translator
B2
B3
B4
NB-IoT Module Series
BC66 Hardware Design
Comment
1.8V power domain
DTE
VDD
CS_SPI
SCLK_SPI
MOSI_SPI
MISO_SPI
30 / 57