AK4560A Datasheet, PDF (30/47 Pages) Asahi Kasei Microsystems – 16bit CODEC with ALC and MIC/HP/SPK-Amps

ASAHI KASEI
[AK4560A]
n Shutter Signal Input
1. Recording
When ADMIX bit is “1”, input signal from SHT pin is attenuated to –4.5dB internally and is mixed to output signal from
ALC1 by a gain of 0dB. Input impedance of SHT pin is 42kΩ (typ.).
When ADMIX bit is “0”, output signal of ALC1 is input to ADC by a gain of 0dB.
ALC1
SHT pin
ADMIX bit
Gain =-4.5dB
Gain=0dB
-
+
ADC
Figure 15. ADMIX Block Diagram
2. Playback
When BEEPS bit is “1”, input signal from SHT pin can be input to Speaker-Amp. This signal level can be adjusted by an
external resistor (R2). An internal resistor value (Rf) is 20k ± 30% Ω. For example, when R2 is 20kΩ, the final output
level from Speaker-Amp becomes “20log₁₀(20k/20k) dB + 5.6dB (Speaker-Amp) = +5.6dB”. (Refer to Figure 16)
n BEEP Input
When BEEPH bit is “1”, input signal from BEEP pin can be input to Headphone-Amp. When BEEPS bit is “1”, input
signal from BEEP pin can be input to Speaker-Amp.
This signal level can be adjusted by an external resistor (R1). An internal resistor value (Rf) is 20k ± 30% Ω. For example,
when R1 is 20kΩ, the final output level from Headphone-Amp becomes
“20log₁₀(20k/20k) dB + 11.8dB (Headphone-Amp block) = +11.8dB”. (Refer to Figure 16)
BEEP
SHT
R1
R2
Rf=20kΩ
-
+
to SPK or HP-Amp
to ADMIX
Figure 16. Block Diagram of BEEP and SHT pin
MS0028-E-00
- 30 -
2000/05