LTE-A Module Series
EM160R-GL_Hardware_Design 24 / 73
3.3. Power Supply
Table 6: Pin Definition of VCC and GND Pins
3.3.1. Voltage Stability Requirements
The power supply range of the module is from 3.135 V to 4.4 V. Ensure that the input voltage never drops
below 3.135 V, otherwise the module will be powered down automatically. The following figure shows the
maximum voltage drop during radio frequency transmission in 3G and 4G networks.
VCC (V)
Burst Transmission
Voltage Ripple
< 100 mV
Voltage Drop
Burst Transmission
3.135 V
Load (A)
Figure 3: Power Supply Limits During Burst Transmission
To decrease the voltage drop, a bypass capacitor of about 220 µF with low ESR should be used, and a
multi-layer ceramic chip capacitor (MLCC) array should also be reserved due to its ultra-low ESR. It is
recommended to use four ceramic capacitors (
1 μF, 100 nF, 33 pF, 10 pF) for composing the MLCC array,
and place these capacitors close to VCC pins. The main power supply from an external application must
be a single voltage source. The width of VCC trace should be not less than 2 mm. In principle, the longer
the VCC trace is, the wider it should be.
In addition, to ensure the stability of the power supply, it is recommended to use a TVS with working peak
reverse voltage
of 5 V.
Pin No.
Pin Name
I/O
DC Characteristics
Description
2, 4, 70, 72, 74
VCC
PI
3.135
–4.4 V
3.7 V typical DC supply
Power supply for the
module
3, 5, 11, 27, 33, 39, 45, 51,
57, 71, 73
GND
Ground