User's Manual

GE864
GE864GE864
GE864-
--
-QUAD Automotive V2 Hardware User Guide
QUAD Automotive V2 Hardware User GuideQUAD Automotive V2 Hardware User Guide
QUAD Automotive V2 Hardware User Guide
1vv0300840 Rev.3 2010-04-08
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 46 of 71
10.2.2.
10.2.2.10.2.2.
10.2.2. Output Lines Characteristics
Output Lines CharacteristicsOutput Lines Characteristics
Output Lines Characteristics
TIP
TIPTIP
TIP:
We suggest driving the load differentially from both output drivers, thus the output
swing will double and the need for the output coupling capacitor avoided. However if
particular OEM application needs also a Single Ended circuitry can be implemented,
but the output power will be reduced four times .
The OEM circuitry shall be designed to reduce the common mode noise typically
generated on the ground plane and to get the maximum power output from the device
(low resistance tracks).
WARNING:
WARNING: WARNING:
WARNING:
The loads are directly connected to the amplifier outputs when in Differential
configuration, through a capacitor when in Single Ended configuration. Using a Single
Ended configuration
, the unused output line must be left open. Not respecting this
constraint, the output stage will be damaged.
TIP :
TIP : TIP :
TIP :
Remember that there are slightly different electrical performances between the two
internal audio amplifiers:
• the “Ear_MT
Ear_MTEar_MT
Ear_MT” lines can directly drive a 16
1616
16 Ω load
load load
load at –12dBFS (**)
(**)(**)
(**) in Differential
configuration
• the “ Ear_HF
Ear_HFEar_HF
Ear_HF” lines can directly drive a 4
44
4 Ω load
load load
load in Differential configurations
• There is no difference if the amplifiers drive an external amplifier
(**)
(**) (**)
(**) 0dBFS is the normalized overall Analog Gain for each Output channel equal to
3,7V
pp
differential