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FIBOCOM_NL952-NA_Hardware_User_Manual
Page 19 of 57
The filter capacitor design for power supply as shown in the following table:
Recommended
capacitance
Application
Description
220uF x 2
Voltage-stabilizing capacitors
Reduce power fluctuations of the module in
operation, requiring capacitors with low ESR.
LDO or DC/DC power supply requires the
capacitor of no less than 440uF
The capacitor for battery power supply
can be reduced to 100~200uF
1uF, 100nF
Digital signal noise
Filter out the interference generated from the
clock and digital signals
39pF, 33pF
700/800, 850/900 MHz frequency
band
Filter out low frequency band RF interference
18pF, 10pF,
8.2pF, 6.8pF
1500/1800, 2100/2300,
2600MHz, 3500/3600/3700MHz
Filter out medium/high frequency band RF
interference
The stable power supply can ensure the normal operation of NL952 module; and the ripple of the power
supply should be less than 300mV in design. Because module support 5CA download, when module
operates with the maximum data transfer throughput, the peak current can reach to upper 2500mA. It
requests the power source voltage should not be lower than 3.3V, otherwise module may shut down or
restart. The power supply requirement is shown in Figure 3-3:
Burst transmit
Burst transmit
min:3.3V
Power supply
Ripple
≤
300mV
Drop
VBAT
≥
3.3V
Figure 3-3 Power Supply Requirement
Logic level
The NL952 module 1.8V logic level definition as shown in the following table:
Parameters
Minimum
Typical
Maximum
Unit
1.8V logic level
1.71
1.8
1.89
V
V
IH
1.3
1.8
1.89
V
V
IL
-0.3
0
0.3
V