User's Guide

UL865 Hardware User Guide
1VV0301050 Rev 2 – 2013-10-09
The power supply circuitry and board layout are a very important part in the full product
design and they strongly reflect on the product overall performance, hence read the
requirements carefully and the guidelines that will follow for a proper design.
The external power supply must be connected to VBATT & VBATT_PA signals and
must fulfill the following requirements:
POWER SUPPLY
Nominal Supply Voltage
3.8 V
Normal Operating Voltage Range
3.40 V÷ 4.20 V
Extended Operating Voltage Range
3.22 V÷ 4.50 V
NOTE:
The Operating Voltage Range MUST never be exceeded; care must be taken in order to
fulfil min/max voltage requirement.
NOTE:
Overshoot voltage (regarding MAX Extended Operating Voltage) and drop in voltage
(regarding MIN Extended Operating Voltage) MUST never be exceeded;
The “Extended Operating Voltage Range” can be used only with complete assumption
and application of the HW User guide suggestions.
If the voltage drop is exceeding the limits it could cause a Power Off of the module.
The Power supply must be higher than 3.22 V to power on the module.