DESCRIPTION
The PCM1723 is a complete, low-cost, stereo audio
digital-to-analog converter (DAC) with a phase-locked
loop (PLL) circuit included. The PLL derives either a
256fS or 384fS system clock from an external 27MHz
reference frequency. The DAC contains a 3rd-order
delta-sigma (?Σ) modulator, a digital interpolation filter,
and an analog output amplifier. The PCM1723 can
accept 16-, 20-, or 24-bit input data in either normal or
I2S formats.
The digital filter performs an 8X interpolation function
and includes selectable features such as soft mute,
digital attenuation and digital de-emphasis. The PLL
can be programmed for sampling at standard digital
audio frequencies as well as one-half and double
sampling frequencies.
The PCM1723 is ideal for applications which combine
compressed audio and video data such as DVD, DVD-
ROM, set-top boxes and MPEG sound cards.