Product Details
●The AD7785 is a low power, low noise, complete analog front ends for high precision measurement applications. It contains a low noise 20-bit Σ-Δ ADC with three differential analog inputs. The on-chip, low noise instrumentation amplifier means that signals of small amplitude can be interfaced directly to the ADC. With a gain setting of 64, the rms noise is 40 nV when the update rate equals 4.17 Hz.
●The device contains a precision low noise, low drift internal band gap reference and can also accept an external differential reference. Other on-chip features include programmable excitation current sources, burnout currents, and a bias voltage generator, the bias voltage generator being used to set the common-mode voltage of a channel to AVDD/2.
●The device can be operated with either the internal clock or an external clock. The output data rate from the part is software-programmable and can be varied from 4.17 Hz to 470 Hz.
●The part operates with a power supply from 2.7 V to 5.25 V. It consumes a current of 400 µA typical and is housed in 16-lead TSSOP packages.
●Applications
● Thermocouple measurements
● RTD measurements
● Thermistor measurements
● Gas analysis
● Industrial process control
● Instrumentation
● Portable instrumentation
● Blood analysis
● Smart transmitters
● Liquid/gas chromatography
● 6-digit DVM
●### Features and Benefits
● Up to 20 bits effective resolution
● RMS noise
● 40 nV @ 4.17 Hz
● 85 nV @ 16.7 Hz
● Current: 400 µA typ
● Power-down: 1 µA max
● Low noise programmable gain instrumentation amp
● Band gap reference with 4 ppm/°C drift typ
● Update rate: 4.17 Hz to 470 Hz
● 3 differential inputs
● Simultaneous 50 Hz/60 Hz rejection
