Siemens TC65 - Figure 21: Differential Loudspeaker Configuration; Figure 22: Single Ended Loudspeaker Configuration; Loudspeaker Circuit

TC65 Hardware Interface Description
Strictly confidential / Draft
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TC65_HD_V00.521 Page 58 of 99 24.05.2005
3.13.3 Loudspeaker Circuit
The GSM module comprises two analog speaker outputs: EP1 and EP2. Output EP1 is able
to drive a load of 8Ohms while the output EP2 can drive a load of 32Ohms. Each interface
can be connected in differential and in single ended configuration. See examples in Figure
21 and Figure 22.
GSM module
AGND
EPNx
EPPx
Figure 21: Differential loudspeaker configuration
Loudspeaker impedance
EPP1/EPN1
Z
L
= typ. 8Ohm
EPP2/EPN2
Z
L
= typ. 32Ohm
GSM module
AGND
EPNx
EPPx
+
C
k
Figure 22: Single ended loudspeaker configuration
Loudspeaker impedance
EPP1/EPN1
Z
L
= typ. 8Ohm
C
k
= 220µF
EPP2/EPN2
Z
L
= typ. 32Ohm
C
k
= 47µF