UMTS/HSPA Module Series
UG96 Hardware Design
UG96_Hardware_Design 28 / 76
Module
VBAT_RF
VBAT_BB
VBAT
C1
100uF
C6
100nF
C7
33pF
C8
10pF
+
+
C2
100nF
C5
100uF
C3
33pF
C4
10pF
D1
Figure 7: Star Structure of the Power Supply
3.6.3. Reference Design for Power Supply
The power design for the module is very important, as the performance of module largely depends on the
power source. The power supply should be able to provide sufficient current up to 2A at least. If the
voltage drop between the input and output is not too high, it is suggested that an LDO should be used to
supply power for module. If there is a big voltage difference between the input source and the desired
output (VBAT), a buck converter is preferred to be used as the power supply.
The following figure shows a reference design for +5V input power source. The typical output of the power
supply is about 3.8V and the maximum load current is 3A.
DC_IN
C1
C2
MIC29302WU
U1
IN
OUT
E
N
G
N
D
A
D
J
2
4
1
3
5
VBAT
100nF
C3
470uF
C4
100nF
R2
100K
47K
R3
470uF
470R
51K
R4
R1
1%
1%
MCU_POWER
_ON/OFF
47K
4.7K
R5
R6
Figure 8: Reference Circuit of Power Supply
It is suggested that customers should switch off power supply for module in abnormal state, and then
switch on power to restart module.
NOTE