Dual 16-Bit Stereo Audio Sigma-Delta ADC

CMOS

The MC145073 is a dual–channel, 16–bit A/D converter intended for use in digital audio systems such as multimedia, DCC, DAT, and professional audio applications. It uses a sigma–delta architecture consisting of a second–order analog modulator and two stages of digital filtering for each channel. The analog modulator samples the input signal at 128 times the output data rate, performs a single–bit quantization, and shapes the quantization noise towards higher frequencies. Subsequent on–chip digital filters reject most of the shaped quantization noise and lower the data rate.

Sixteen unique user–selectable interfacing modes make the MC145073 compatible with a multitude of application interfacing requirements. A single 5 V supply and a power–down mode reduce power supply requirements, making the part attractive for portable applications.

? Single Supply, Operating Voltage Range: 4.5 to 5.5 V

? 128x OSR Sigma–Delta Modulator

? 82 dB Typical S/(N+D)

? Analog Inputs Can Be Driven as Either Differential or Single–Ended

? Clock Input May Be 128x, 256x, or 384x the Output Data Rate

? Out–of–Range Input Signals Internally Limited

? On–Chip Digital Filters:

5th Order Decimate–by–32 Comb Filter

121 Tap Decimate–by–4 FIR Filter

? User–Selectable Digital Filter Transition Bands

? Versatile Serial Digital Output Interface:

Configurable as Master or Slave

Data Can Be Either Left– or Right–Justified

Interfaces to DSP56000/1 and TMS320? DSPs

I2S or Japanese Interface Compatibility

CS5326 Compatible Interface Mode

Multiplexing of Two MC145073s Accommodated

? Power–Down Mode Consumption: 2.0 mW

? Operating Temperature Range: – 40 to 85°C