AD85020-2x20W Stereo/1x40W Mono Digital Audio Amplifier With 36 Bands EQ Functions DataSheet

Description
    AD85020 is a digital audio amplifier capable of driving
a pair of 8Ω,20W or a single 4Ω,40W speaker output.
In headphone output mode, it can delivered 25mW
into 32Ω load for head phone output.
AD85020 provides advanced audio processing
functions, such as volume control, 36 EQ bands, audio
mixing, 3D surround sound and Dynamic Range
Control (DRC). These are fully programmable via a
simple I2C control interface. Robust protection circuits
are provided to protect AD85020 from damage due to
accidental erroneous operating condition. The full
digital circuit design of AD85020 is tolerant of noise
and PVT (Process, Voltage, and Temperature)
variation. AD85020 is pop free during instantaneous
power on/off or mute/shut down switching because of
its robust built-in anti-pop circuit

Features

16/18/20/24-bits input with I2S, Left-alignment
and Right-alignment data format

Multiple sampling frequencies (Fs)
8kHz and 32kHz / 44.1kHz / 48kHz and
64kHz / 88.2kHz / 96kHz and
128kHz / 176.4kHz / 192kHz

System clock = 64x, 128x, 192x, 256x, 384x,
512x, 576x, 768x, 1024x Fs
MCLK system:
256x~4096x Fs for 8kHz
64x~1024x Fs for 32kHz / 44.1kHz / 48kHz
64x~512x Fs for 64kHz / 88.2kHz / 96kHz
64x~256x Fs for 128kHz / 176.4kHz / 192kHz
BCLK system:
64xFs for 32kHz / 44.1kHz / 48kHz
64xFs for 64kHz / 88.2kHz / 96kHz
64xFs for 128kHz / 176.4kHz / 192kHz

Supply voltage
1.8V or 3.3V for digital I/O
3.3V for analog circuit and headphone driver
4.5V~26V for loudspeaker driver

Speaker or headphone out selection

Line-driver maximum output swing into 10kΩ
- 2Vrms at 3.3V supply voltage

Headphone output power
25mW x 2ch into 32Ω @ 0.1% THD+N

Speaker output power
20W x 2ch into 8Ω @ <1% THD+N@24V

Sound processing including：
36 bands parametric speaker EQ
Volume control (+24dB~-103dB, 0.125dB/step)
Dynamic range control
Three Band plus post Dynamic range control
Power Clipping
Programmed 3D surround sound
Channel mixing
Noise gate with hysteresis window
Bass/Treble tone control
DC-blocking high-pass filter
Pre-scale/post-scale
Virtual Bass/exciter
Smart bass

Anti-pop design

Level meter and power meter

I2S output with selectable audio DSP point

Supports I2C control without clock

I2C control interface with selectable device
address

Internal PLL

Support initial EEPROM setting

Protection
■ OCP
■ OVP
■ UVP
■ OTP
■ DCP

Closed-loop structure with good PSRR

Supports Filter-less operating

Applications

Boom-box, CD and DVD receiver, docking system

Powered speaker

Wireless audio

AI speaker