Neoway N720 - Power Control Interfaces; Vbat; Figure 2-2 Current Peaks and Voltage Drops

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 14
2.3 Power Control Interfaces
Name
Pin No.
I/O
Function
Remarks
VBAT
17/18/19
P
Main power supply input
3.3 V to 4.3 V (typical value: 3.8 V)
VDDIO_1P8
45
P
1.8 V power supply
output
Supply power for IO level shifting circuit.
Load capability: <50 mA
Added ESD protection when using this pin.
RESET
32
DI
Reset input
Low level triggers reset
PON_TRIG
34
DI
PON_TRIG
High level triggers the ON status
PWRKEY
33
DI
Power ON/OFF
Low level triggers the ON status
2.3.1 VBAT
VBAT is the power supply input pin of the module. Its input voltage ranges from 3.3 V to 4.3 V and the
typical value is 3.8 V. In addition to baseband, it supplies power to RF power amplifier. The performance
of the VBAT power supply is a critical path to module's performance and stability. The peak input current
at the VBAT pin can be up to 2A when the signal is weak and the module works at the maximum
transmitting power. The voltage will encounter a drop in such a situation. The module might restart if the
voltage drops lower than 3.3 V.
Figure 2-2 Current peaks and voltage drops
Keep the voltage above 3.3 V
3.3 V
0 ms
3.7 ms 7.4 ms 10.7 ms
T
2A
Voltage
Input
current
3.8 V