AK4538 Datasheet, PDF (32/70 Pages) Asahi Kasei Microsystems – 16Bit DS CODEC with MIC/HP/SPK-AMP

ASAHI KASEI
[AK4538]
n BEEP Input
When the BMBPS bit is set to “1”, the stereo beep input is powered up. And when the BPSHP bit is set to “1”, the input
signals from the BEEPL and BEEPR pins are mixed to Headphone outputs. When the BPSSP bit is set to “1”, the signal of
(BEEPL + BEEPR)/2 is input to Speaker-amp. When the BMBPM bit is set to “1”, mono beep input is powered up. And
when the BPMHP bit is set to “1”, the input signal from the BEEPM pin to Headphone-amp. When the BPMSP bit is set to
“1”, the signal from the BEEPM pin is input to Speaker output. The external resisters Ri adjust the signal level of each
BEEP input that are mixed to Headphone and Speaker outputs.
The signal from the BEEPM pin is mixed to the Headphone-amp through a –20dB gain stage. The signal from the BEEPM
pin is mixed to the Speaker-amp without gain. The internal feedback resistance is 20k ± 30%Ω.
Ri
BEEPL
Ri
BEEPR
Ri
BEEPM
Rf = 20kΩ
Rf = 20kΩ
BPSHP
BPMHP
HPL
MIX
-20dB
HPR
MIX
BPSHP
Rf = 20kΩ
BPSSP
1/2
SPK
1/2
MIX
AK4538
BPMSP
Figure 25. Block Diagram of BEEP pins
MS0198-E-01
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