The AD1871 is a stereo audio ADC intended for digital audio
applications requiring high performance analog-to-digital
conversion. It features two 24-bit conversion channels each
with programmable gain amplifier (PGA), multibit sigma-delta
modulator, and decimation filters. Each channel provides 105 db
of dynamic range, making the AD1871 suitable for applications
such as digital audio recorders and mixing consoles.
Each of the AD1871’s input channels (left and right) can be
configured as either differential or single-ended (two inputs
muxed with internal single-ended-to-differential conversion).
The input PGA features a gain range of 0 dB to 12 dB in steps
of 3 dB. The Σ-Δ modulator features a proprietary multibit
architecture that realizes optimum performance over an audio
bandwidth with standard audio sampling rates of 32 kHz up to
96 kHz. The decimation filter response features very low passband
ripple and excellent stop-band attenuation.
The AD1871’s audio data interface supports all common interface
formats such as I2S, left-justified, right-justified as well as other
modes that allow for convenient connection to general-purpose
digital signal processors (DSPs). The AD1871 also features an
SPI compatible serial control port that allows for convenient
control of device parameters and functionality such as sample
word-width, PGA settings, interface modes, and so on.
The AD1871 operates from a single 5 V power supply—with
an optional digital interfacing capability of 3.3 V. It is housed in
a 28-lead SSOP package and is characterized for operation
over the temperature range –40°C to +105°C.