ASAHI KASEI [AK4702]
MS0187-E-00 2002/11
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GENERAL DESCRIPTION
The AK4702 offers the ideal features for digital set-top-box systems. Using AKM's multi-bit architecture
for its modulator, the AK4702 delivers a wide dynamic range while preserving linearity for improved
THD+N performance. The AK4702 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
AK4702 also including the audio switches and volumes designed primarily for digital set-top-box
systems. The AK4702 is offered in a space saving 48-pin LQFP package.
FEATURES
DAC
o Sampling Rates Ranging from 8kHz to 50kHz
o 18bit 8x FIR Digital Filter
o 2nd order Analog LPF
o On chip Buffer with Single-ended Output
o Digital de-emphasis for 32k, 44.1k and 48kHz sampling
o I/F format: 18bit MSB justified, 18/16bit LSB justified, I2S
o Master clock: 256fs, 384fs
o High Tolerance to Clock Jitter
Analog switches for SCART
Audio section
o THD+N: -86dB (@2Vrms)
o Dynamic Range: 96dB (@2Vrms)
o Stereo Analog Volume with Zero-cross Detection Circuit
(+6dB to –60dB & Mute)
o Five Analog Inputs
Two Stereo Input (TV, VCR SCART)
One Mono Input for Tone
o Five Analog Outputs
Two Stereo Outputs (TV, VCR SCART)
One Mono Output
o Loop-through mode for standby
o Pop Noise Free Circuit for Power on/off
Video section
o 75ohm driver
o 6dB Gain for Outputs
o Adjustable gain
o Four CVBS/Y inputs (ENCx2, TV, VCR),
Three CVBS/Y output (RF, TV, VCR)
o Three R/C inputs (ENCx2, VCR), Two R/C output (TV, VCR)
o Bi-directional control for VCR-Chroma/Red
o Two G and B inputs (ENC, VCR), One G and B outputs (TV)
Power supply
o 5V+/-5% and 12V+/-5%
o Low Power Dissipation
Package
o Small 48pin LQFP
2ch DAC with AV SCART switch
AK4702