Analog Devices

The AD7156 delivers a complete signal processing solution for capacitive sensors, featuring an ultralow power converter with fast response time.The AD7156 uses an Analog Devices, Inc., capacitance-to-digital converter (CDC) technology, which combines features important for interfacing to real sensors, such as high input sensitivity and high tolerance of both input parasitic ground capacitance and leakage current.The integrated adaptive threshold algorithm compensates for any variations in the sensor capacitance due to environmental factors like humidity and temperature or due to changes in the dielectric material over time.By default, the AD7156 operates in standalone mode using the fixed power-up settings and indicates detection on two digital outputs. Alternatively, the AD7156 can be interfaced to a micro-controller via the serial interface, the internal registers can be programmed with user-defined settings, and the data and status can be read from the part.The AD7156 operates with a 1.8 V to 3.6 V power supply. It is specified over the temperature range of −40°C to +85°C.ApplicationsButtons and switchesProximity sensingContactless switchingPosition detectionLevel detectionPortable products

The AD7170 is a very low power 12-bit analog-to-digital converter (ADC). It contains a precision 12-bit sigma-delta (Σ-Δ) ADC and an on-chip oscillator. Consuming only 135 μA, the AD7170 is particularly suitable for portable or battery operated products where very low power is a requirement. The AD7170 also has a power-down mode in which the device consumes 5 μA, thus increasing the battery life of the product.For ease-of-use, all the features of the AD7170 are controlled by dedicated pins. Each time a data read occurs, eight status bits are appended to the 12-bit conversion. These status bits contain a pattern sequence that can be used to confirm the validity of the serial transfer. The output data rate of the AD7170 is 125 Hz, whereas the settling time is 24 ms. The AD7170 has one differential input and a gain of 1. This is useful in applications where the user needs to use an external amplifier to implement system-specific filtering or gain requirements.The AD7170 operates with a power supply from 2.7 V to 5.25 V. It is available in a 10-lead LFCSP package.The AD7171 is a 16-bit version of the AD7170. It has the same feature set as the AD7170 and is pin-for-pin compatible.INTERFACE2-wire serial (read-only device)SPI compatibleSchmitt trigger on SCLKAPPLICATIONSPressure measurementIndustrial process controlPortable instrumentation

TThe AD7172-2 is an intelligent, low noise, low power, multiplexed, Σ-Δ analog-to-digital converter (ADC) with 2- or 4-channel (fully differential/single-ended) inputs for low bandwidth signals. The AD7172-2 has a maximum channel scan rate of 6.21 kSPS (161 µs) for fully settled data. The output data rates range from 1.25 SPS to 31.25 kSPS.The AD7172-2 integrates key analog and digital signal conditioning blocks to allow users to configure an individual setup for each analog input channel in use via the SPI. Integrated true rail-to-rail buffers on the analog inputs and external reference inputs provide easy to drive high impedance inputs. The precision 2.5 V low drift (2 ppm/°C) band gap internal reference (with an output reference buffer) adds embedded functionality to reduce the external component count.The digital filter allows simultaneous 50 Hz and 60 Hz rejection at a 27.27 SPS output data rate. The user can switch between different filter options according to the demands of each channel in the application, with further digital processing functions such as offset and gain calibration registers, which are also configurable on a per channel basis. General-purpose inputs/outputs (GPIOs) control external multiplexers synchronous to the ADC conversion timing.The specified operating temperature range is −40°C to +105°C. The AD7172-2 is in a 24-lead TSSOP package.ApplicationsProcess control: PLC/DCS modules- Temperature and pressure measurementMedical and scientific multichannel instrumentationChromatography

The AD7175-8 is a low noise, fast settling, multiplexed, 8-/16- channel (fully/pseudo differential) Σ-Δ analog-to-digital converter (ADC) for low bandwidth inputs. It has a maximum channel scan rate of 50 kSPS (20 µs) for fully settled data. The output data rates range from 5 SPS to 250 kSPS.The AD7175-8 integrates key analog and digital signal condition-ing blocks to allow users to configure an individual setup for each analog input channel in use. Each feature can be user selected on a per channel basis. Integrated true rail-to-rail buffers on the analog inputs and external reference inputs provide easy to drive high impedance inputs. The precision 2.5 V low drift (2 ppm/°C) band gap internal reference (with output reference buffer) adds embedded functionality to reduce external component count.The digital filter allows simultaneous 50 Hz and 60 Hz rejection at a 27.27 SPS output data rate. The user can switch between different filter options according to the demands of each channel in the application. The ADC automatically switches through each selected channel. Further digital processing functions include offset and gain calibration registers, configurable on a per channel basis.The device operates with a 5 V AVDD1 . AVSS supply, or with ±2.5 V AVDD1/AVSS, and 2.5 V to 5 V AVDD2 and IOVDD supplies. The specified operating temperature range is .40°C to +105°C. The AD7175-8 is available in a 40-lead LFCSP package.APPLICATIONSProcess control: PLC/DCS modulesTemperature and pressure measurementMedical and scientific multichannel instrumentationChromatography

The AD7177-2 is a 32-bit low noise, fast settling, multiplexed, 2-/4-channel (fully/pseudo differential) Σ-Δ analog-to-digital converter (ADC) for low bandwidth inputs. It has a maximum channel scan rate of 10 kSPS (100 µs) for fully settled data. The output data rates range from 5 SPS to 10 kSPS.The AD7177-2 integrates key analog and digital signal conditioning blocks to allow users to configure an individual setup for each analog input channel in use. Each feature can be user selected on a per channel basis. Integrated true rail-to-rail buffers on the analog inputs and external reference inputs provide easy to drive high impedance inputs. The precision 2.5 V low drift (2 ppm/°C) band gap internal reference (with output reference buffer) adds embedded functionality to reduce external component count.The digital filter allows simultaneous 50 Hz and 60 Hz rejection at a 27.27 SPS output data rate. The user can switch between different filter options according to the demands of each channel in the application. The ADC automatically switches through each selected channel. Further digital processing functions include offset and gain calibration registers, configurable on a per channel basis.The device operates with a 5 V AVDD1 supply, or with ±2.5 V AVDD1/AVSS, and 2 V to 5 V AVDD2 and IOVDD supplies. The specified operating temperature range is −40°C to +105°C. The AD7177-2 is available in a 24-lead TSSOP package.ApplicationsProcess control: PLC/DCS modulesTemperature and pressure measurementMedical and scientific multichannel instrumentationChromatography

The AD7190 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 be interfaced directly to the ADC.The device can be configured to have two differential inputs or four pseudo differential inputs. The on-chip channel sequencer allows several channels to be enabled, and the AD7190 sequentially converts on each enabled channel. This simplifies communication with the part. 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 two digital filter options. The choice of filter affects the rms noise/noise-free resolution at the programmed output data rate, the settling time, and the 50 Hz/60 Hz rejection. For applications that require all conversions to be settled, the AD7190 includes a zero latency feature.The part operates with 5 V analog power supply and a digital power supply from 2.7 V to 5.25 V. It consumes a current of 6 mA. It is housed in a 24-lead TSSOP package.APPLICATIONSWeigh scalesStrain gauge transducersPressure measurementTemperature measurementChromatographyPLC/DCS analog input modulesData acquisitionMedical and scientific instrumentation

The AD7191 is a low noise, complete analog front end for high precision measurement applications. It contains a low noise, 24-bit sigma-delta (Σ-Δ) ADC. The on-chip low noise gain stage means that signals of small amplitude can be interfaced directly to the ADC. It contains two differential analog inputs. The part also includes a temperature sensor that can be used for temperature compensation.For ease-of-use, all the features of the AD7191 are controlled by dedicated pins. The on-chip PGA has a gain of 1, 8, 64, or 128, supporting a full-scale differential input of ±5 V, ±625 mV, ±78 mV, or ±39 mV. The output data rate can be programmed to 10 Hz, 50 Hz, 60 Hz, or 120 Hz. Simultaneous 50 Hz and 60 Hz rejection is obtained when the output data rate is set to 10 Hz or 50 Hz; 60 Hz only rejection is obtained when the output data rate is set to 60 Hz. The AD7191 can be operated with the internal clock, or an external clock can be used.The part operates with a power supply of 3 V to 5.25 V. It consumes a current of 4.35 mA. It is available in a 24-lead TSSOP package.ApplicationsWeigh scalesStrain gauge transducersPressure measurementMedical and scientific instrumentation

The AD7193 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 four differential inputs or eight pseudo differential inputs. The on-chip channel sequencer allows several channels to be enabled simultaneously, and the AD7193 sequentially converts on each enabled channel, simplifying communication with the part. 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 filter, including a fast settling option. Variables such as output data rate and settling time are dependent on the option selected. The AD7193 also includes a zero latency option.The part operates with a power supply from 3 V to 5.25 V. It consumes a current of 4.65 mA, and it is available in a 28-lead TSSOP package and a 32-lead LFCSP package.ApplicationsPLC/DCS analog input modulesData acquisitionStrain gage transducersPressure measurementTemperature measurementFlow measurementWeigh scalesChromatographyMedical and scientific instrumentation