3
Power supply
25
Power supply
Voltage requirements
The power of CE915GM modules comes from the carrier board, and there is a common 3V
battery supply for the real-time clock (RTC). Power supply requirements are as follows.
Inrush current
The inrush current to the module depends on the rise time of the main power from the
carrier board.
Figure 8
and
Figure 9
show the inrush currents when the power supply is 12V with 5V
standby.
Figure 8. Inrush current @ 12V
Figure 9. Inrush current @ +5V standby
Supply
Current/Watts
Maximum Ripple
12V
4.1A/49W
DC 5% ripple 100mV @ 0~20MHz
5V Standby
1A/5W
1
1
The inrush current will be higher than this value during system
boot on the 5V standby power rail.
DC 5% ripple 50mV @ 0~20MHz
3V Battery
6µA
2.0 — 3.6V
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