Telit Wireless Solutions GE863-PY, GE863-QUAD manual Battery Source Power Supply Design Guidelines

GE863-QUAD

GE863-PY

1vv0300715 Rev. 1 - 19/09/06

An example of switching regulator with 12V input is:

4.2.1.3 Battery Source Power Supply Design Guidelines

•The desired nominal output for the power supply is 3.8V and the maximum voltage allowed is 4.2V, hence a single 3.7V Li-Ion cell battery type is suited for supplying the power to the Telit GE863-QUAD/PY module.

The three cells Ni/Cd or Ni/MH 3,6 V Nom. battery types or 4V PB types MUST NOT BE USED DIRECTLY since their maximum voltage can rise over the absolute maximum voltage for the GE863-QUAD/PY and damage it.

NOTE: DON'T USE any Ni-Cd, Ni-MH, and Pb battery types directly connected with GE863- QUAD/PY. Their use can lead to overvoltage on the GE863-QUAD/PY and damage it. USE ONLY Li-Ion battery types.

•A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current absorption peaks, a 100μF tantalum capacitor is usually suited.

•Make sure the low ESR capacitor (usually a tantalum one) is rated at least 10V.

•A protection diode should be inserted close to the power input, in order to save the GE863- QUAD/PY from power polarity inversion. Otherwise the battery connector should be done in a way to avoid polarity inversions when connecting the battery.

•The battery capacity must be at least 500mAh in order to withstand the current peaks of 2A; the suggested capacity is from 500mAh to 1000mAh.

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