AKM公司的AK4482 是用于數字音頻設備的高性價比的兩路24位Sigma-Delta 數模轉換器(DAC),采用AKM的多比特架構,具有很寬的動態范圍,達到111dB,THD+N為-100dB,電源電壓4.75 ∼ 5.25V,支持216kHz取樣速率,非常適合BD和AC-3放大器系統.本文介紹了AK4482主要特性,方框圖,典型應用框圖,外接LPC濾波器電路圖以及評估板AKD4482-SB框圖和電路圖.

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主要特性:

?? 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)

圖1.AK4482方框圖

圖2.AK4482典型應用電路框圖

圖3.外接2階LPC濾波器電路圖(采用運放和單電源)

圖4.外接2階LPC濾波器電路圖(采用運放和雙電源)

評估板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.

圖4.評估板AKD4482-SB方框圖

圖5.評估板AKD4482-SB電路圖(1)

圖6.評估板AKD4482-SB電路圖(2)
詳情請見:
http://www.asahi-kasei.co.jp/akm/en/product/ak4482/ak4482_f01e.pdf
和
http://www.asahi-kasei.co.jp/akm/en/product/ak4482/akd4482-sb0-00e.pdf