Quectel SC600Y-EM Series Hardware Design page 51

pre-charge mode. The charging current is 450mA (100mA~450mA programmable, 450mA by
default).
⚫ Constant current mode (CC mode): When the battery voltage is increased to between the
maximum pre-charge voltage and 4.2V (3.6V~4.5V programmable, 4.2V by default), the system will
switch to CC mode. The charging current is programmable from 300mA~3000mA. The default
charging current is 500mA for USB charging and 2A for adapter.
⚫ Constant voltage mode (CV mode): When the battery voltage reaches the final value 4.2V, the
system will switch to CV mode and the charging current will decrease gradually. When the charging
current reduces to about 100mA, the charging is completed.
Table 9: Pin Definition of Charging Interface
Pin Name Pin No.
USB_VBUS 41, 42
36, 37,
VBAT
38
BAT_ID 17
BAT_PLUS 27
BAT_MINUS 28
BAT_THERM 29
SC600Y&SC600T modules support battery temperature detection in the condition that the battery
integrates a thermistor (47K 1% NTC thermistor with B-constant of 4050K by default;
SDNT1608X473F4050FTF of SUNLORD is recommended) and the thermistor is connected to
BAT_THERM pin. If BAT_THERM pin is not connected, there will be malfunctions such as boot error,
battery charging failure, battery level display error, etc.
A reference design for battery charging circuit is shown as below.
SC600Y&SC600T_Hardware_Design
I/O Description
Charging power input.
PI/PO Power supply output for OTG device.
USB/charger insertion detection.
PI/PO Power supply for the module
AI Battery type detection
Differential input signal of battery voltage
AI
detection (plus)
Differential input signal of battery voltage
AI
detection (minus)
AI Battery temperature detection
Smart LTE Module Series
SC600Y&SC600T Hardware Design
Comment
Vmax=10V
Vmin=4.0V
Vnorm=5.0V
Vmax=4.4V
Vmin=3.55V
Vnorm=3.8V
If unused, keep this
pin open.
Must be connected.
Must be connected.
Internally pulled up.
Externally connected
to GND via a 47K
NTC resistor.
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