Product Info

NB-IoT Module Series
BC660K-GL Hardware Design
BC660K-GL_Hardware_Design
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Table 8: Power Supply Pins
3.5.2. Reference Design for Power Supply
Power design for a module is critical to its performance. It is recommended to use a low quiescent current
LDO with output current capacity of 0.5 A as the power supply for BC660K-GL.
Lithium-thionyl chloride
(Li-SOCl2) batteries and Lithium manganese oxide (LiMn2O4) batteries
can also be used as the power
supply. The supply voltage of the module ranges from 2.2 V to 4.3 V. When the module is working, ensure
its input voltage will never drop below 2.2 V; otherwise the module will be abnormal.
For better power performance, it is recommended to place a 100 μF tantalum capacitor with low ESR
(ESR = 0.7 Ω) and three ceramic capacitors (100 nF, 100 pF and 22 pF) near the VBAT pins. Also, it is
recommended to add a TVS diode on the VBAT trace (near VBAT pins) to improve surge voltage
withstand capability. In principle, the longer the VBAT trace is, the wider it should be. A reference circuit
for power supply is illustrated in the following figure.
Figure 5: Reference Circuit for Power Supply
3.5.3. Power Supply Voltage Detection*
You can use AT+CBC to monitor and query the current VBAT voltage. The unit of the voltage value is
millivolt. For detailed information about the command, see document [2].
Pin Name
Pin No.
Description
Min.
Typ.
Max.
Unit
VBAT
42, 43
Power supply for the
module
2.2
3.3
4.3
V
GND
1, 27, 34, 36,
37, 40, 41, 56,
57, 58
GND