Production Data
WM9715L
PHONE OUTPUT (MONOOUT)
The MONOOUT output (pin 33) is intended for connection to the TX side of a wireless chipset. The
signal is generated in a dedicated mono mixer; it is not necessarily a mono mix of the stereo outputs
HPOUTL/R or LOUT2/ROUT2 (see “Audio Mixers” section).
The MONOOUT volume can be controlled by writing to register 06h. When MONOOUT is not used,
the output buffer can be disabled to save power (see “Power Management” section). The MONOOUT
pin remains at the same DC level (the reference voltage on the VREF pin), so that no click noise is
produced when muting or un-muting.
REGISTER
ADDRESS
BIT
LABEL
MUTE
DEFAULT
DESCRIPTION
06h
15
1
Mute MONOOUT
MONOOUT
Volume
1: Mute
0: No Mute
7
ZC
0
Zero Cross Enable
0: Change gain immediately
1: Change gain only on zero crossings,
or after time-out
4:0
MONOOUT
VOL
00000
(0dB)
MONOOUT Volume
00000: 0dB (maximum)
00001: -1.5dB
… (1.5dB steps)
11111: -46.5dB
Table 18 MONOOUT Control
THERMAL SENSOR
The speaker and headphone outputs can drive very large currents. To protect the WM9715L from
becoming too hot, a thermal sensor has been built in. If the chip temperature reaches approximately
150°C, and the ENT bit is set, the WM9715L de-asserts bit 11 in register 54h, which can be set up to
generate an interrupt to the CPU (see “Interrupt Control” section).
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
5Ch
2
ENT
0
Enable thermal sensor
0: Disabled
1: Enabled
54h
11
TI
1
Thermal sensor (interrupt bit)
1: Temperature below 150°C
0: Temperature above 150°C
See also “Interrupt Control” section.
Table 19 Thermal Cutout Control
PD Rev 4.0 December 2007
33
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
