Product Details
●The AD7731 is a complete analog front-end for process control applications. The device has a proprietary programmable gain front end that allows it to accept a range of input signal ranges, including low level signals, directly from a transducer. The sigmadelta architecture of the part consists of an analog modulator and a low pass programmable digital filter, allowing adjustment of filter cutoff, output rate and settling time.
●The part features three buffered differential programmable gain analog inputs (which can be configured as five pseudo-differential inputs), as well as a differential reference input. The part operates from a single +5 V supply and accepts seven unipolar analog input ranges: 0 to +20 mV, +40 mV, +80 mV, +160 mV, +320 mV, +640 mV and +1.28 V, and seven bipolar ranges: ±20 mV, ±40 mV, ±80 mV, ±160 mV, ±320 mV, ±640 mV and ±1.28 V. The peak-to-peak resolution achievable directly from the part is 16 bits at an 800 Hz output rate. The part can switch between channels with 1 ms settling time and maintain a performance level of 13 bits of peak-to-peak resolution.
●The serial interface on the part can be configured for three-wire operation and is compatible with microcontrollers and digital signal processors. The AD7731 contains self-calibration and system calibration options and features an offset drift of less than 5 nV/°C and a gain drift of less than 2 ppm/°C.
●The part is available in a 24-lead plastic DIP, a 24-lead SOIC and 24-lead TSSOP package.
●Applications
● Process Control
● PLCs/DCS
● Industrial Instrumentation
●### Features and Benefits
● 24-Bit Sigma-Delta ADC
● 16 Bits p-p Resolution at 800 Hz Output Rate
● Programmable Output Rates up to 6.4 kHz
● Programmable Gain Front End
● ±0.0015% Nonlinearity
● Buffered Differential Inputs
● Programmable Filter Cutoffs
● _FAST_Step™
● Mode for Channel Sequencing
● Single Supply Operation
● FASTStep is a trademark of Analog Devices, Inc.
