GE863-PRO3 Hardware User Guide
1vv0300773a Rev. 0 - 24/01/08
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5.4.1.1 + 5V input Source Power Supply Design Guidelines
The desired output for the power supply is 3.8V, hence there's not a big difference between the
input source and the desired output and a linear regulator can be used. A switching power supply
will not be suited because of the low drop out requirements.
When using a linear regulator, a proper heat sink shall be provided in order to dissipate the power
generated.
A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current
absorption peaks close to the GE863-PRO3, a 100μF tantalum capacitor is usually suited.
Make sure the low ESR capacitor on the power supply output (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-PRO3
from power polarity inversion.
An example of linear regulator with 5V input is: