
ASAHI KASEI 
AKM CONFIDENTIAL
[AK4704] 
Rev. 0.5 
2004/1 
- 1 - 
GENERAL DESCRIPTION 
The AK4704 offers the ideal features for digital set-top-box systems. Using AKM's multi-bit architecture 
for its modulator, the AK4704 delivers a wide dynamic range while preserving linearity for improved 
THD+N performance. The AK4704 integrates a combination of SCF and CTF filters, removing the need 
for high cost external filters and increasing performance for systems with excessive clock jitter. The 
AK4704 also including the audio switches, volumes, video switches, video filters, etc. designed primarily 
for digital set-top-box systems. The AK4704 is offered in a space saving 48-pin LQFP package.
FEATURES 
        DAC 
 Sampling Rates Ranging from 8kHz to 50kHz 
 64dB High Attenuation 8x FIR Digital Filter 
 2nd order Analog LPF 
 On chip Buffer with Single-ended Output 
Digital de-emphasis for 32k, 44.1k and 48kHz sampling 
 I/F format: 24bit MSB justified, I
S, 18/16bit LSB justified
 Master clock: 256fs, 384fs 
 High Tolerance to Clock Jitter 
        Analog switches for SCART 
         Audio section 
 THD+N: -86dB (@2Vrms) 
 Dynamic Range: 96dB (@2Vrms) 
Stereo Analog Volume with Zero-cross Detection Circuit
(+6dB to –60dB & Mute)
Six Analog Inputs 
     Two Stereo Input (TV&VCR SCART) 
     One Stereo Input (changeover to internal DAC) 
Five Analog Outputs 
   Two Stereo Outputs (TV, VCR SCART) 
    One Mono Output (Modulator) 
Pop Noise Free Circuit for Power on/off 
         Video section 
Integrated LPF: -40dB@27MHz 
75ohm driver 
6dB Gain for Outputs 
 Adjustable gain 
Four CVBS/Y inputs (ENCx2, TV, VCR),  
Three CVBS/Y output (RF, TV, VCR) 
Three R/C inputs (ENCx2, VCR), Two R/C output (TV, VCR) 
Bi-directional control for VCR-Chroma/Red 
Two G and B inputs (ENC, VCR), One G and B outputs (TV) 
Y/C Mixer for RF output 
VCR input monitor 
         Loop-through Mode for standby 
         Auto-Startup Mode for power saving 
        SCART pin#16(Fast Blanking), pin#8(Slow Blanking) Control 
        Power supply 
5V+/-5% and 12V+/-5% 
Low Power Dissipation / Low Power Standby Mode
Package
Small 48pin LQFP
2ch 24bit DAC with AV SCART switch 
AK4704
= Target Spec =