GENERAL DESCRIPTION
The AD7711 is a complete analog front end for low frequency measurement applications. The device accepts low level signals directly from a transducer and outputs a serial digital word. It employs a sigma-delta conversion technique to realize up to 24 bits of no missing codes performance. The input signal is applied to a proprietary programmable gain front end based around an analog modulator.
   
FEATURES
    Charge Balancing ADC
        24 Bits No Missing Codes
        ±0.0015% Nonlinearity
    Two-Channel Programmable Gain Front End
        Gains from 1 to 128
        One Differential Input
        One Single-Ended Input
    Low-Pass Filter with Programmable Filter Cutoffs
    Ability to Read/Write Calibration Coefficients
    RTD Excitation Current Sources
    Bidirectional Microcontroller Serial Interface
    Internal/External Reference Option
    Single or Dual Supply Operation
    Low Power (25 mW typ) with Power-Down Mode
        (7 mW typ)
   
APPLICATIONS
    RTD Transducers
    Process Control
    Smart Transmitters
    Portable Industrial Instruments