Smart Module Series
SC200R&SC262R_Series_Hardware_Design 47 / 124
SC200R series module supports battery temperature detection in the condition that the battery integrates
a thermistor (
47 kΩ 1 % NTC thermistor with a B-constant of 4050 K by default) and the thermistor is
connected to BAT_THERM pin. If the BAT_THERM pin is not connected, there will be malfunctions such
as battery charging failure, battery level display error, etc. The default battery temperature range is
-3.0 °C to 48.5 °C.
A reference design for the battery charging circuit is shown below.
GND
BAT_SNS
BAT_THERM
VBAT
0R
100
μF
NTC
VBAT
33 pF
1
μF
ESD
ESD
1
2
3
USB_VBUS
Adapter or USB
Module
Battery
GND
C1
C2
C3
R1
D1
D2
1
μF
C2
NM_1 nF
C4
Figure 10: Reference Design for Battery Charging Circuit
Mobile devices such as mobile phones or handheld POS systems are powered by batteries. For different
batteries, you should modify the charging and discharging curve correspondingly to achieve the best
performance.
If the thermistor is not available in the battery, or an adapter is utilized to power the module, you must
connect BAT_THERM to GND via a 47 kΩ resistor. Otherwise, the system may mistakenly judge that the
battery temperature is abnormal, and therefore cause battery charging failure.
BAT_SNS must be connected. Otherwise, the module will have abnormalities in voltage detection, as well
as associated problems with power-on/off and battery charging/discharging.
CHG_SEL
127
DI
Charging select
If you use an internal charging chip,
keep this pin open.
If you use an external charging chip,
connect it to GND.