AK4951AEN Datasheet, PDF (97/105 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/HP/SPK-AMP

[AK4951A]
■ Beep Signal Output from Headphone Amplifier
1. Power down DAC → Headphone Amplifier
PMVCM bit
PMBP bit
(Addr:00H, D6-5)
PMOSC bit
(Addr:01H, D7)
(1)
(2)
(6)
(5)
Example: default
(1) Addr:00H, Data:60H
(2) Addr:01H, Data:80H
Addr:12H, D4 bit = “1”
BEEPH bit
(Addr:12H, D4)
PMHPL/R bits
(Addr:01H, D5-4)
HPL pin
HPR pin
(3)
(4)
>66.2ms
0V
Beep Output
0V
(3) Addr:01H, Data:B0H
BEEP Signal Output
(4) Addr:01H, Data:00H
(5) Addr:12H, D4 bit = “0”
(6) Addr:00H, Data:00H
Figure 66. “BEEP-Amp → Headphone-Amp” Output Sequence
<Sequence>
Clock input is not necessary when the AK4951A is operating only on the path of “BEEP-Amp →
Headphone-Amp”.
(1) Power up VCOM and BEEP Amplifier: PMVCM = PMBP bit = “0” → “1”
Beep Amplifier is powered-up after rise-up VCOM. Power up time for VCOM is 2ms (max).
(2) Power up Oscillator: “0” → “1”
Set up the path of BEEP-Amp → Headphone-Amp: BEEPH bit= “0” → “1”
(3) Power up Headphone Amplifier: PMHPL bit or PMHPR bit = “0” → “1”
Period (3) should be set according to the time constant of a capacitor and a resistor that are
connected to the BEEP pin. Pop noise may occur if the Headphone-Amp output is enabled before
the BEEP-Amp input is stabilized. The BEEP-Amp is powered up after VCOM voltage rise. The
maximum rise-up time of VCOM is 2msec.
e.g. R=86k(max), C=0.1F: Recommended Wait Time (max.): 2msec + 10 = 88ms or more
The power-up time of Headphone Amplifier block is 66.2ms (max).
(4) Power down Headphone Amplifier: PMHPL = PMHPR bits = “1” → “0”
(5) Power down Oscillator: PMOSC bit = “1” → “0”
Disable the path of BEEP → Headphone-Amp: BEEPH bit = “1” → “0”
(6) Power down VCOM and BEEP Amplifier: PMVCM = PMBP bits = “1” → “0”
016001936-E-00
- 97 -
2016/03