Quectel SC20 Series - Power Supply; Power Supply Pins; Voltage Stability Requirements

Smart Module Series
SC20_Series_Hardware_Design 34 / 133
3.4. Power Supply
3.4.1. Power Supply Pins
SC20 series provides two VBAT_RF pins and two VBAT_BB pins for connection with the external power
supply. The VBAT_RF pins are used for the RF part of the module and the VBAT_BB pins are used for
the baseband part of the module.
3.4.2. Voltage Stability Requirements
The power supply range of the module is 3.5–4.2 V, and the recommended value is 3.8 V. The power
supply performance, such as load capacity, voltage ripple, etc. directly influences the module’s
performance and stability. Under ultimate conditions, the transient peak current of the module may surge
up to 3 A. If the supply voltage is not enough, there will be voltage drops, and if the voltage drops below
3.1 V, the module will be turned off automatically. Therefore, make sure the input voltage never drops
RESET_N 179 DI
Resets the
module
Disabled by default
and can be enabled
through software
configuration.
USB_BOOT 46 DI
Forces the
module to enter
emergency
download mode
You can force the
module to enter
emergency
download mode by
pulling it up to
LDO5_1V8 during
power-up.
CHARGE_SEL 127 DI Charger select
If you use an
internal charging
chip, keep this pin
open.
If you use an
external charging
chip, connect it to
GND.
Reserved Pins
Pin Name Pin No. Comment
RESERVED
151, 152, 153, 154, 155, 156, 157, 158, 159, 183, 187,
190, 191, 194, 195, 196, 197, 199, 202, 203, 204, 205,
206, 207, 210
Keep these pins
open.