ADI AD7195BCPZ

The AD7195 is a low noise, complete analog front end for high precision measurement applications. It integrates a low noise, 24-bit Σ-Δ ADC. The on-chip low noise gain stage enables small signals to be directly input. The AD7195 incorporates AC excitation to eliminate induced DC offset voltages in bridge sensors. The device can be configured for two differential inputs or four pseudo-differential inputs. The on-chip channel sequencer allows multiple channels to be enabled, with the AD7195 performing conversions sequentially on each enabled channel, simplifying communication with the device. The on-chip 4.92 MHz clock can be used as the clock source for the ADC; alternatively, an external clock or crystal can be used. The output data rate of the device can be varied from 4.7 Hz to 4.8 kHz. The device offers two digital filter options. The choice of filter affects the RMS noise and noise-free resolution at the programmed output data rate, settling time, and 50 Hz/60 Hz rejection. For applications requiring settling on every conversion, the AD7195 features zero latency. The device operates from a 5 V analog supply and a 2.7 V to 5.25 V digital supply, consumes 6 mA, and is available in a 32-lead LFCSP package.

• AC or DC sensor excitation
• RMS noise: 8.5 nV (4.7 Hz, G = 128)
• 16-bit noise-free resolution (2.4 kHz, G = 128)
• Noise-free resolution up to 22.5 bits (G = 7)
• Offset drift: 5 nV/°C
• Gain drift: 1 ppm/°C
• Stable time drift characteristics
• 2 differential/4 pseudo-differential input channels
• Auto channel sequencer
• 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
• Supply AVDD: 4.75 V to 5.25 V, DVDD: 2.7 V to 5.25 V
• Current: 6 mA
• Temperature range: -40°C to +105°C
• Package: 32-lead LFCSP
• 3-wire serial interface
• SPI, QSPI, MICROWIRE, and DSP compatible
• Schmitt trigger input on SCLK pin

• Electronic scales
• Strain gauge sensors
• Pressure measurement
• Temperature measurement
• Chromatography
• PLC/DCS analog input modules
• Data acquisition
• Medical and scientific instruments