Reference Design For Power Supply - Quectel RM520N-GL Hardware Design

In addition, to guarantee stability of the power supply, it is recommended to use a TVS with working peak
reverse voltage of 5 V.
VCC (3.7 V Typ.)
+
+
TVS

3.3.2. Reference Design for Power Supply

Power design is critical as the module's performance largely depends on its power source. If the voltage
difference between the input and output is not too big, it is suggested that an LDO is used when supplying
power for the module. If there is a big voltage difference between the input source and the desired output
(VCC = 3.7 V Typ.), a buck DC-DC converter is preferred.
The following figure shows a reference design for +5.0 V input power source based on a DC-DC
converter. The typical output of the power supply is about 3.7 V and the maximum load current is 3.0 A.
PWR_IN
+
+
C1 C2
C3
C4
220 μ F 220 μ F
100 nF
33 pF
R7
4.7k
PWR_EN
R8
47k
RM520N-GL_Hardware_Design
C2 C6 C8
C4
220 μ F
6.8 nF 220 pF
100nF
C1
C3 C5 C7
220 μ F
100nF 220pF 68 pF
Figure 6: Reference Circuit for VCC
R1
88.7k
R2 VFB
35.7k
R3 R4
10k 182k
Q1
NPN
C6
10 nF 10 nF
C5
NM_0.5pf
Figure 7: Reference Circuit for Power Supply
VCC
C10
68 pF
GND
VCC
C9
C11 C12
15 pF
9.1 pF 4.7 pF
GND
U1
VIN PH
VIN PH
C6
VIN PH
100 nF
EN BOOT
VSNS PWRGD
PWRGD
COMP GND
RT/CLK GND
SS AGND
EP
VFB
C7
5G Module Series
Module
2, 4
PMU
3, 5, 11
70, 72, 74
APT
27, 33, 39,
45, 51, 57,
71, 73
L1
μ
1.5 H
+
+
C8 C9 C10
100 μ F
100 uF 100nF
PWR_OUT
R5
C11
330k 1%
33pF
R6
100k 1%
31 / 84