AK4632VN AKM [Asahi Kasei Microsystems], AK4632VN Datasheet - Page 37

• Manufacturer Part Number: AK4632VN
• Description: 16-Bit ?? Mono CODEC with ALC & MIC/SPK/Video-AMP
• Manufacturer: AKM [Asahi Kasei Microsystems]

ASAHI KASEI
<Control Sequence of Speaker Amp>
Speaker blocks (MOUT, ALC2 and Speaker-amp) can be powered-up/down by controlling the PMSPK bit. When the
PMSPK bit is “0”, the MOUT, SPP and SPN pins are placed in a Hi-Z state.
When the PMSPK bit is “1” and SPPS bit is “0”, the Speaker-amp enters 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. And then the Speaker output gradually changes to the
SVDD/2 voltage and this mode can reduce pop noise at power-up. When the AK4632 is powered-down, pop noise can be
also reduced by first entering power-save-mode.
(Note)
MS0396-E-00
“t1” depends on the time constant of input resistance of MIN and capacitor between MOUT pin and MIN pin. If
Speaker-Amp output is enabled before MIN-Amp (ALC2) becomes stable, pop noise may occur.
Ex) C of MOUT pin – MIN pin = 0.1 µF, Input resistance of MIN pin = 36kΩ(Max) : t1 = 5τ = 18ms
PMSPK bit
SPPS bit
SPN pin
SPP pin
C of MOUT pin – MIN pin and the Input resistance(Rin) of MIN pin compose of HPF which cut off
frequency(fc) are the followings.
fc = 66Hz@Rin=24kΩ(typ), 133Hz@Rin=12kΩ(min), 44Hz@Rin=36kΩ(max)
Hi-Z
Figure 35. Circuit of Speaker Output(Load Capacitance > 30pF)
Figure 36. Power-up/Power-down Timing for Speaker-Amp
SPK-Amp
SVDD/2
Hi-Z
>t1(Note)
SPP
SPN
- 37 -
≥10Ω
≥10Ω
ZD
ZD
SVDD/2
Hi-Z
>0
Hi-Z
[AK4632]
2005/06