© Confidential
Page: 49 / 97
This document is the sole and exclusive property of WAVECOM. Not to be distributed or divulged without prior
written agreement.
WM_PRJ_Q2686_PTS_001-010
June 30, 2009
Q2686 Wireless CPU
®
3.11.2
Speaker Features
The connection is single-ended on SPK1 and is differential or single-ended on
SPK2. Using a differential connection to reject common mode noise and TDMA
noise is strongly recommended. Moreover in single-ended mode, the power is
divided by 4. When using a single-ended connection, be sure to have a very
good ground plane, a very good filtering as well as shielding in order to avoid
any disturbance on the audio path.
Parameter
Typ
Unit
Connection
Z (SPK1P, SPK1N)
16 or 32
Ω
single-ended mode
Z (SPK2P, SPK2N)
4
Ω
single-ended mode
Z (SPK2P, SPK2N)
8
Ω
Differential mode
3.11.2.1
Speakers Outputs Power
The both speakers maximum power output are not similar, that is due to the
different configuration between the Speaker1 which is only single ended and
the speaker2 which can be differential, so speaker2 can provides more power.
The maximal specifications given below are available with the maximum
power output configuration values set by an AT command. The typical values
are recommended.
3.11.2.1.1
SPK1 Speaker Outputs
With the SPK1 interface, only single ended speaker connection is allowed
Equivalent circuits of SPK1
