NB-IoT
Module Series
BC660K-GL Hardware Design
BC660K-GL_Hardware_Design 19 / 57
1. Keep all reserved and unused pins unconnected.
2.
1)
When VIO_SEL is grounded and VBAT
˂
3.3 V, VDD_EXT = VBAT;
When VIO_SEL is grounded and VBAT
≥ 3.3 V, VDD_EXT = 3.3 V;
When VIO_SEL is floating, VDD_EXT = 1.8 V.
3.
“*” means under development.
3.3. Operating Modes
The following table briefly describes the three working modes of the module.
GPIO4
6
DIO
General-purpose
input/output
GRFC Interfaces*
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
GRFC1
54
DO
Generic RF
controller
V
OL
max = 0.27 V
V
OH
min = 1.44 V
1.8 V power
domain.
If unused, keep
these pins open.
GRFC2
55
DO
Generic RF
controller
V
OL
max = 0.27 V
V
OH
min = 1.44 V
Others
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
VIO_SEL
52
DI
IO Voltage
selection
-
Control
VDD_EXT
voltage
selection
1)
Reserved Pins
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RESERVED
2, 8, 21
–23, 25, 26, 28–33, 44–51, 53
Keep these pins
open.
NOTES
