AD7194

8-Channel, 4.8 kHz, Ultralow Noise, 24-Bit Sigma-Delta ADC with PGA AD7194 FEATURES Fast settling filter option 8 differential/16 pseudo differential input channels RMS noise: 11 nV at 4.7 Hz (gain = 128) 15.5 noise-free bits at 2.4 kHz (gain = 128) Up to 22 noise-free bits (gain = 1) Offset drift: ±5 nV/°C Gain drift: ±1 ppm/°C Programmable gain (1 to 128) Output data rate: 4.7 Hz to 4.8 kHz Internal or external clock Simultaneous 50 Hz/60 Hz rejection 4 general-purpose digital outputs Power supply AVDD: 3 V to 5.25 V DVDD: 2.7 V to 5.25 V Current: 4.65 mA Temperature range: −40°C to +105°C Package: 32-lead LFCSP Interface 3-wire serial SPI, QSPI™, MICROWIRE™, and DSP compatible Schmitt trigger on SCLK Pressure measurement Temperature measurement Flow measurement Weigh scales Chromatography Medical and scientific instrumentation GENERAL DESCRIPTION The AD7194 is a low noise, complete analog front end for high precision measurement applications. It contains a low noise, 24-bit sigma-delta (Σ-Δ) analog-to-digital converter (ADC). The on-chip low noise gain stage means that signals of small amplitude can interface directly to the ADC. The device can be configured to have eight differential inputs or sixteen pseudo differential inputs. The on-chip 4.92 MHz clock can be used as the clock source to the ADC or, alternatively, an external clock or crystal can be used. The output data rate from the part can be varied from 4.7 Hz to 4.8 kHz. The device has a very flexible digital fil...