AK4534 Datasheet, PDF (31/64 Pages) Asahi Kasei Microsystems – 16Bit CODEC with MIC/HP/SPK-AMP

ASAHI KASEI
[AK4534]
n Speaker Output
Mono signal [(L+R)/2] converted from stereo DAC output and BEEP input signal can be output via Speaker-amp which is
controlled by BTL. ALC2 circuit is available for DAC output signal. This Speaker-amp can deliver a maximum power of
300mW(typ)@THD=10%, 250mW(typ)@THD=0.1% into 8 ohm load at HVDD=3.3V. Maximum output power is
137mW(typ) when DAC output signal is output via ALC2 circuit as system design example (Figure 31). When BEEP input
is used for DAC output, maximum power becomes 300mW. Figure 16 and Figure 17 indicates connection examples for
300mW output.
Speaker blocks (MOUT2, ALC2 and Speaker-amp) can be powered up/down by controlling the PMSPK bit. When the
PMSPK bit is “0”, the MOUT2, SPP and SPN pins are placed in a Hi-Z state.
When the 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 HVDD/2 voltage. And then the Speaker output gradually changes to the HVDD/2 voltage and this
mode can reduce pop noise at power-up. When the AK4534 is powered down, pop noise can be also reduced by first
entering power-save-mode.
PMSPK bit
SPPS bit
SPP pin
Hi-Z
Hi-Z
SPN pin Hi-Z ^HVDD/2
HVDD/2
Hi-Z
Figure 15. Power-up/Power-down Timing for Speaker-amp
[Connection Example for 300mW output]
1) Using BEEPM pin
AK4534
20k
± 30%
SPK-Amp
SPP
MOUT2
0.047u _13k
45%AVDD
BEEPM
BPMSP
SPN
Figure 16. Connection example for 300mW output using BEEPM pin
MS0133-E-03
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