GENERAL DESCRIPTION
The AD7661 is a 16-bit, 100 kSPS, charge redistribution SAR analog-to-digital converter that operates from a single 5 V power supply. The part contains a high speed 16-bit sampling ADC, an internal conversion clock, internal reference, error correction circuits, and both serial and parallel system interface ports. The AD7661 is hardware factory-calibrated and comprehensively tested to ensure ac parameters such as signal-to-noise ratio (SNR) and total harmonic distortion (THD), in addition to the more traditional dc parameters of gain, offset, and linearity.
The AD7661 is available in a 48-lead LQFP and a tiny 48-lead LFCSP with operation specified from –40°C to +85°C.

FEATURES
   2.5 V internal reference: typical drift 3 ppm/°C
      Guaranteed max drift 15 ppm/°C
   Throughput: 100 kSPS
   INL: ±2.5 LSB max (±0.0038% of full scale)
   16-bit resolution with no missing codes
   S/(N+D): 88 dB min @ 20 kHz
   THD: –96 dB max @ 20 kHz
   Analog input voltage range: 0 V to 2.5 V
   Both AC and DC specifications
   No pipeline delay
   Parallel and serial 5 V/3 V interface
   SPI®/QSPITM/MICROWIRETM/DSP compatible
   Single 5 V supply operation
   Power dissipation
      16 mW typ, 160 µW @ 1 kSPS without REF
      40 mW typ with REF
   48-lead LQFP and 48-lead LFCSP packages
   Pin-to-pin compatible with PulSAR ADCs

APPLICATIONS
   Data acquisition
   Medical instruments
   Digital signal processing
   Spectrum analysis
   Instrumentation
   Battery-powered systems
   Process control