Product Info

LPWA Module Series
BG95 Series Hardware Design
BG95_Series_Hardware_Design 39 / 106
drop below 3.2 V.
⚫ BG95-MF: The typical power supply of BG95-MF is 3.8 V.
The following figure shows the voltage drop during burst transmission in 2G network of BG95-M3/-M5.
The voltage drop is less in LTE Cat M1 and/or LTE Cat NB2 networks.
VBAT
Burst
Transmission
Min.3.3V
Ripple
Drop
Burst
Transmission
Figure 4: Power Supply Limits during Burst Transmission (BG95-M3/-M5)
To decrease voltage drop, a bypass capacitor of about 100 µF with low ESR should be used, and a
multi-layer ceramic chip capacitor (MLCC) array should also be reserved due to its low ESR. It is
recommended to use three ceramic capacitors (100 nF, 33 pF, 10 pF) for composing the MLCC array,
and place these capacitors close to VBAT pins. The main power supply from an external application has
to be a single voltage source and can be expanded to two sub paths with star structure. The width of
VBAT_BB trace should be no less than 0.6 mm, and the width of VBAT_RF trace should be no less than 2
mm. In principle, the longer the VBAT trace is, the wider it will be.
In addition, in order to get a stable power source, it is suggested to use a TVS with low leakage current
and suitable reverse stand-off voltage, and also it is recommended to place it as close to the VBAT pins
as possible. The following figure shows the star structure of the power supply.
Module
VBAT_RF
VBAT_BB
VBAT
C1
100uF
+
+
100nF
33pF
10pF
D1
TVS
100uF
100nF
33pF
10pF
C2 C3
C4
C5 C6 C7
C8
R1 0R
R2 0R
Figure 5: Star Structure of the Power Supply