CC864-DUAL Hardware User Guide
1vv0300791 Rev 4.4 – 2011-01-26
Reproduction forbidden without Telit Communications S.p.A’s. written authorization - All Rights Reserved.
Page 47 of 63
The design of the amplifier should comply with the following guidelines:
The input to the amplifier must be taken from the “EAR_HF” audio path of the
module.
The amplifier must have a mute control to be used while not in conversation
to eliminate background noise and to save power.
The power to the amplifier must be decoupled as much as possible from the
CC864-DUAL power supply by either keeping separate wires or by placing
bypass capacitors of adequate value close to the amplifier power input pins.
The biasing voltage of the amplifier must be stabilized with low ESR (e.g.,
tantalum) capacitor of adequate value.
The figure below shows an example of car kit amplifier schematic: