User's Manual

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Note d’étude / Technical document : URD1– OTL
5665.3 – 003 / 72238 Edition 01
Document Sagemcom Reproduction et divulgation interdites
Sagemcom document. Reproduction and disclosure prohibited
Pad Name Min Max
VBACKUP 1000µA
4.13.3 Charge by internal HiLoNC V2 charging function
The charging function is available on the HiLoNC V2 without any additional external power supply (the charging
power supply is provided by the HiLoNC V2).
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Charge of the back-up battery occurs only when main power supply VBAT is provided.
The recommended schematic is given hereafter:
Figure 28: Backup battery or 10µF Capacitor internally charged
The resistor R depends on the charging current value provided by the battery manufacturer.
The charging curve which is done by the HiLoNC V2 is given hereafter:
Figure 29: Charging curve of backup battery
4.13.4 Backup Battery technology
4.13.4.1 Manganese Silicon Lithium-Ion rechargeable Battery
SAGEMCOM does not recommend using this kind of technology because of the following drawbacks:
• The maximum discharge current is limited (Shall be compliant with the module characteristics).
• The over-discharge problem: most of the Lithium Ion rechargeable batteries are not able to recover their
charge when their voltage reaches a low-level voltage. To avoid this, it is necessary to add a safety
component to disconnect the backup .battery in case of over–discharge condition. In such a case, this
implementation is too complicated (too much components for that function).
• The charging current has to be regulated.
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SAGEMCOM does not recommend using this kind of backup battery technology.
VBACKUP
HiLoNC V2
10µF capacitor
VBACKUP
HiLoNC V2
R
Backup battery