AKM’s AK4482 is a cost-effective two-way 24-bit Sigma-Delta digital-to-analog converter (DAC) for digital audio equipment. It adopts AKM’s multi-bit architecture and has a wide dynamic range, reaching 111dB. THD+N is -100dB, power supply voltage 4.75 ∼ 5.25V, support 216kHz sampling rate, very suitable for BD and AC-3 amplifier systems. This article introduces the main features of AK4482, block diagram, typical application block diagram, external LPC filter circuit diagram and evaluation board AKD4482-SB block diagram and circuit diagram.
The AK4482 is a cost-effective 24-bit DAC for digital audio equipments. The modulator uses AKM’s multi-bit architecture, delivering wide dynamic range. The AK4482 has fully differential switched-cap filter outputs, removing the need for AC coupling capacitors and increasing performance for systems with excessive clock jitter. The AK4482 support up to 216kHz sampling rate, ideal for BD and AC-3 amplifier systems. It is housed in a space saving 16pin TSSOP package.
AK4482 main features:
? Sampling Rate: 8kHz ∼ 216kHz
? 128 x Over Sampling (Normal Speed Mode)
? 64 x Over Sampling (Double Speed Mode)
? 32 x Over Sampling (Quad Speed Mode)
? 24 Bit 8 x FIR Digital Filter
– High Quality Sound Short Delay Sharp Roll-off Filter (less than 6/fs)
– High Quality Sound Short Delay Slow Roll-off Filter (less than 6/fs)
– Sharp Roll-off Filter
– Slow Roll-off Filter
? Optimized Layout for Sound Quality
? SCF
? Digital De-emphasis (32kHz, 44.1kHz, 48kHz)
? Soft Mute
? Digital ATT (256 Steps)
? Digital I/F Format: 24Bit MSB justified, 24/20/16Bit LSB justified, I2S
? Master Clock: 256fs, 384fs, 512fs or 768fs (Normal Speed Mode)
128fs, 192fs, 256fs or 384fs (Double Speed Mode)
128fs or 192fs (Quad Speed Mode)
?THD+N: -100dB
?Dynamic Range: 111dB
? High Tolerance to Clock Jitter
? Power Supply: 4.75 ∼ 5.25V
? Package: 16pin TSSOP (6.4mm x 5.0mm)
Figure 1. AK4482 block diagram
Figure 2. Typical application circuit block diagram of AK4482
Figure 3. Circuit diagram of an external 2nd-order LPC filter (using op amp and single power supply)
Figure 4. Circuit diagram of an external 2nd-order LPC filter (using op amps and dual power supplies)
Evaluation Board AKD4482-SB
The AKD4482-SB is an evaluation board for AK4482, which is 192kHz sampling 24Bit ΔΣ DAC. The AKD4482-SB includes a LPF which can add differential analog outputs from the AK4482 and also has a digital interface. Therefore, it is easy to evaluate the AK4482.
Figure 4. Block Diagram of Evaluation Board AKD4482-SB
Figure 5. Evaluation Board AKD4482-SB Circuit Diagram (1)
Figure 6. Evaluation Board AKD4482-SB Circuit Diagram (2)
For details, see:
http://www.asahi-kasei.co.jp/akm/en/product/ak4482/ak4482_f01e.pdf
and
http://www.asahi-kasei.co.jp/akm/en/product/ak4482/akd4482-sb0-00e.pdf