AK4649 Datasheet, PDF (60/96 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/SPK-AMP

[AK4649]
< Speaker-Amp Control Sequence >
Speaker-Amp is powered-up/down by PMSPK bit. When PMSPK bit is “0”, both SPP and SPN pins are in Hi-Z state.
When PMSPK bit is “1” and SPPSN bit is “0”, the Speaker-Amp enters power-save mode. In this mode, the SPP pin is
placed in Hi-Z state and the SPN pin outputs SVDD/2 voltage.
When the PMSPK bit is “1” after the PDN pin is changed from “L” to “H”, the SPP and SPN pins rise up from
power-save-mode. In this mode, the SPP pin is placed in a Hi-Z state and the SPN pin goes to SVDD/2 voltage. Because
the SPP and SPN pins rise up at power-save-mode, this mode can reduce pop noise. When the AK4646 is powered-down,
pop noise can be also reduced by first entering power-save-mode.
PMSPK
0
1
SPPSN
x
0
1
Mode
SPP
SPN
Power-down
Hi-Z
Hi-Z
Power-save
Hi-Z
SVDD/2
Normal Operation Normal Operation Normal Operation
Table 56 Speaker-Amp Mode Setting (x: Don’t care)
(default)
PMSPK bit
SPPSN bit
>1ms
SPP pin
Hi-Z
Hi-Z
SPN pin Hi-Z ^SVDD/2
SVDD/2
Hi-Z
Figure 43. Power-up/Power-down Timing for Speaker-Amp
MS1023-E-01
- 60 -
2010/08