wm9712l Wolfson Microelectronics plc, wm9712l Datasheet - Page 74

• Manufacturer Part Number: wm9712l
• Description: Ac?97 Audio And Touchpanel Codec
• Manufacturer: Wolfson Microelectronics plc

WM9712L
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BTL LOUDSPEAKER OUTPUT
COMBINED HEADSET / BTL EAR SPEAKER
COMBINED HEADSET / SINGLE-ENDED EAR SPEAKER
LOUT2 and ROUT2 can differentially drive a mono 8Ω loudspeaker as shown below.
Figure 27 Speaker Output Connection (INV = 1)
The right channel is inverted by setting the INV bit, so that the signal across the loudspeaker is the
sum of left and right channels.
In smartphone applications with a loudspeaker and separate ear speaker (receiver), a BTL ear
speaker can be connected at the OUT3 pin, as shown below.
Figure 28 Combined Headset / BTL Ear Speaker (OUT3SRC = 00)
The ear speaker and the headset play the same signal. Whenever the headset is plugged in, the
headphone outputs are enabled and OUT3 disabled. When the headset is not plugged in, OUT3 is
enabled (see “Jack Insertion and Auto-Switching”)
Instead of a BTL ear speaker, a single-ended ear speaker can also be used, as shown below.
Figure 29 Combined Headset / Single-ended Ear Speaker (OUT3SRC = 01)
WM9712L
WM9712L
WM9712L
INV = 1
OUT3
HPOUTL
HPOUTR
HPGND = 0V
OUT3
HPOUTL
HPOUTR
HPGND = 0V
-1
BTL ear
speaker
ROUT2VOL
LOUT2VOL
ear speaker
(single-ended)
LOUT2
ROUT2
Stereo: V
Mono: V
SPKR
SPKR
= M-(-M) = 2M
= R-(-L) = L+R
PD Rev 4.5 August 2006
Production Data
74