UMTS/HSPA+ Module Series
UG89 Hardware Design
UG89_Hardware_Design 23 / 73
3.5. Power Supply
3.5.1. Power Supply Pins
UG89 provides two VBAT pins for connection with the external power supply.
The following table shows the details of power supply and GND pins.
Table 7: VBAT and GND Pins
3.5.2. Decrease Voltage Drop
The power supply range of the module is 3.3V~4.5V. Please make sure that the input voltage will never
drop below 3.3V. If the voltage drops to below 3.3V, the module will be turned off automatically. The
following figure shows the voltage drop during burst transmission in 2G network. The voltage drop will be
less in 3G networks.
level. In this mode, the module can still receive paging message, SMS, voice call and
TCP/UDP data from the network normally.
Power Down
Mode
In this mode, the power management unit (PMU) shuts down the power supply,
software goes inactive and the serial interfaces are not accessible. However, the
VBAT pins are still powered.
Pin Name
Pin No.
Description
Min.
Typ.
Max.
Unit
VBAT
4, 57
Power supply for module
3.3
3.8
4.5
V
GND
3, 5, 8,37,
39, 41, 52,
58~62, 64~67,
73,
82~84,
89~97, 106
110~120
Ground
-
-
-
-