ALT1210MOD-VZ-01 User Module
Rev 1.0
Altair Semiconductor Proprietary and Confidential
12
4.
Operational Guidelines
4.1.
Power Supplies Considerations
The ALT1210MOD-VZ-01 has 4 seperated power supply inputs in order to allow max
flexibility to the developers at the application level, to design their products based
on their unique requirements or tradeoffs such as cost, size or power consumption.
4.1.1.
VBAT (pins #15,#16 and #70)
This is the main power supply to the integrated PMIC that produces all required
supplies for the system. The allowed range for this supply is 3.4 to 4.2V.
It is designed to be connected directly to a Li-ion battery for the most simple
devices, but can also be supplied from an external supply if the battery range is not
in compatible to the VBAT allowed range or if further power optimization is
required.
4.1.2.
VPA (pins #46, #99)
This is a dedicated power supply for the RF PAs output stage. This supply max
voltage can be 4.3V. The min voltage required in order to meet the TX conformance
requirements (mainly ACLR and SEM) at the max TX output power (23dbm) is 3.0V.
There are several options to supply the RF PAs inside the module.
For simple applications wishing to optimize BOM cost or size (at the expense of
power consumption), it is possible to supply this rail directly from the battery (Host
needs to disable the Modem when the battery voltage drops towards 3.0V).
In applications wishing to optimize the power consumption (at the expense of BOM
cost) it is possible to use an external DCDC converter (buck or buck-boost
depending on the battery range) to supply the PAs.
It is very important to make sure this DCDC has a rating of more than 600mA output
current, have an enable pin and is configured by default to 3.0V or higher.
The mod
em uses “FEM_CTRL2” pin#31 to enable the DCDC only during actual TX
periods to reduce as much as possible power consumption.
4.1.3.
1V8_IO_IN (pin #61)
This is a dedicated power supply for the digital IOs interface. This is usually supplied
from the same supply powering the host IOs. The allowed range for this supply is
1.71 to 1.89V.
4.1.4.
VDD_RET_IN (pin #6)
This is a dedicated power supply for the DDR memory inside the module. The
allowed range for this supply is 1.71 to 1.89V.
There are two options to supply the DDR.
The first one is using the integrated LDO output (“
VO18R_OUT
”
pin #62) for that.
This also requires connecting “RETLE_N_OUT” pin #21 to “RETLE_N_IN” pin #76,
this configuration uses the relevant output control to put the DDR in retention state
when the modem enters lite hibernation state. The advantage of this configuration