Quectel Smart Wi-Fi Module Series, Руководство пользователя

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SC20-W_Manual_R1.0 Confidential / Released 17 / 41
ESR. The capacitor is able to power the real-time clock for 45 seconds.
3.6. Power Output
SC20-W supports output of regulated voltages for peripheral circuits.
Table 3: Power Description
Pin Name Voltage Range (V) Default Voltage (V) Driving Current (mA) IDLE
LDO5_1V8 1.75~3.337 1.8 20 KEEP
LDO6_1V8 1.75~3.337 1.8 100 No output
LDO17_2V85 1.75~3.337 2.85 300 No output
SD_LDO12 1.75~3.337 2.95 50
SD_LDO11 1.75~3.337 2.95 600
3.7. Battery Charge and Management
SC20-W module can recharge over-discharged batteries. The battery charger in SC20-W module
supports trickle charging, constant current charging and constant voltage charging modes, which
optimizes the charging procedure for Li-ion batteries.

Trickle charging: There are two steps in this mode. When the battery voltage is below 2.8V, a 90mA
trickle charging current is applied to the battery. When the battery voltage is charged up and is
between 2.8V and 3.2V, the charging current can be set to 450mA maximally.

Constant current mode (CC mode): When the battery is increased to between 3.2V and 4.2V, the
system will switch to CC mode. The maximum charging current is 1.44A when adapter is used for
battery charging; and the maximum charging current is 450mA while USB charging.

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 battery
level reaches 100%, the charging is completed.
SC20-W module supports battery temperature detection in the condition that the battery integrates a
thermistor (47K 1%, B4050 NTC thermistor by default; SDNT1608X473F4050FTF of SUNLORD is
recommended) and the thermistor is connected to VBAT_THERM pin. The default temperature range is
from -3.0 to 48.5°C. If VBAT_THERM pin is not connected, there will be malfunctions such as battery
charging failure, battery level display error, etc.