Harman Kardon HK 990/230 Service Manual page 65

ASAHI KASEI
Asynchronous Multi-Channel Audio CODEC with DIR/T
The AK4683 is a single chip CODEC that includes two channels of ADC and four channels of DAC. The ADC
outputs 24bit data and the DAC accepts up to 24bit input data. The ADC has the Enhanced Dual Bit
architecture with wide dynamic range. The DAC introduces the new developed Advanced Multi-Bit
architecture, and achieves wider dynamic range and lower outband noise. The also has digital audio receiver
(DIR) and transmitter (DIT) compatible with 192kHz, 24bits. The DIR can automatically detect a Non-PCM bit
stream such as Dolby Digital (AC-3)*.
The AK4683 has a dynamic range of 100dB for ADC, 106dB for DAC and is well suited for digital TV and
home theater system.
* Dolby Digital (AC-3) is a trademark of Dolby Laboratories.
ADC/DAC part
Asynchronous ADC/DAC Operation
6:1 Input Selector with Pre-amp
2ch 24bit ADC
4ch 24bit DAC
Stereo Headphone Amp with Volume
High Jitter Tolerance
MS0427-E-01
GENERAL DESCRIPTION
FEATURES
- 64x Oversampling
- Sampling Rate up to 96kHz
- Linear Phase Digital Anti-Alias Filter
- Single-Ended Input
- S/(N+D): 90dB
- Dynamic Range, S/N: 100dB
- Digital HPF for Offset Cancellation
- Channel Independent Digital Volume (+24/-103dB, 0.5dB/step)
- Soft Mute
- Overflow Flag
- 128x Oversampling
- Sampling Rate up to 192kHz
- 24bit 8 times Digital Filter
- Single-Ended Outputs
- S/(N+D): 90dB
- Dynamic Range, S/N: 106dB
- Channel Independent Digital Volume (+12/-115dB, 0.5dB/step)
- Soft Mute
- De-emphasis Filter (32kHz, 44.1kHz, 48kHz)
- Zero Detect Function
- 50mW at 16ohm
- Click-noise free at Power on/off
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[AK4683]
AK4683
2005/11