GSM/GPRS Module Series
M66 Hardware Design
M66_Hardware_Design Confidential / Released 20 / 80
SIM_ RST
12
DO
SIM reset
V
OL
max=
0.15×SIM_VDD
V
OH
min=
0.85×SIM_VDD
SIM_
GND
10
SIM ground
ADC
PIN Name
PIN No.
I/O
Description
DC Characteristics
Comment
AVDD
8
PO
Reference voltage of
ADC circuit
V
O
max=2.9V
V
O
min=2.7V
V
O
norm=2.8V
If unused,
keep this pin
open.
ADC0
9
AI
General purpose analog to
digital converter.
Voltage range:
0V to 2.8V
If unused,
keep this pin
open.
PCM
PIN Name
PIN No.
I/O
Description
DC Characteristics
Comment
PCM_ CLK 30
DO
PCM clock
V
IL
min= 0V
V
IL
max=
0.25×VDD_EXT
V
IH
min=
0.75×VDD_EXT
V
IH
max=
0.2
V
OH
min=
0.85×VDD_EXT
V
OL
max=
0.15×VDD_EXT
If unused,
keep this pin
open.
PCM_
SYNC
31
DO
PCM frame
synchronization
PCM_
IN
32
DI
PCM data input
PCM_
OUT
33
DO
PCM data output
Antenna Interface
PIN Name
PIN No.
I/O
Description
DC Characteristics
Comment
RF_
ANT
35
IO
GSM antenna pad
Impedance of 50Ω
BT_
ANT
26
IO
BT antenna pad
Impedance of 50Ω
If unused,
keep this pin
open.
Transmitting Signal Indication
PIN Name
PIN No.
I/O
Description
DC Characteristics
Comment
RFTXMON 25
DO
Transmission signal
indication
V
OH
min=
0.85×VDD_EXT
V
OL
max=
If unused,
keep this pin
open.
Quectel
Confidential