User's Manual

GE866-DUAL Hardware User Guide
1VV0301051 Rev. 2 – 2014-04-07 7
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Reserved. Page 28 of 82
Mod. 0805 2011-07 Rev.2
An example of linear regulator with 5V input is:
6.3.1.2. +
12V input Source Power Supply Design Guidelines
• The desired output for the power supply is 3.8V, hence due
to the big difference between the input source and the
desired output, a linear regulator is not suited and shall
not be used. A switching power supply will be preferable
because of its better efficiency especially with the 2A
peak current load represented by the GE866-QUAD.
• When using a switching regulator, a 500kHz or more
switching frequency regulator is preferable because of its
smaller inductor size and its faster transient response.
This allows the regulator to respond quickly to the current
peaks absorption.
• In any case the frequency and Switching design selection is
related to the application to be developed due to the fact
the switching frequency could also generate EMC
interferences.
• For car PB battery the input voltage can rise up to 15,8V
and this should be kept in mind when choosing components:
all components in the power supply must withstand this
voltage.
• 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 on the power supply output
(usually a tantalum one) is rated at least 10V.
• For Car applications a spike protection diode should be
inserted close to the power input, in order to clean the
supply from spikes.
• A protection diode should be inserted close to the power
input, in order to save the GE866-QUAD from power polarity