Analog Devices

The AD7762 is a high performance, 24-bit Σ-Δ analog-to-digital converter (ADC). It combines wide input bandwidth and high speed with the benefits of Σ-Δ conversion with a performance of 106 dB SNR at 625 kSPS, making it ideal for high speed data acquisition. Wide dynamic range combined with significantly reduced anti-aliasing requirements simplify the design process. An integrated buffer to drive the reference, a differential amplifier for signal buffering and level shifting, an overrange flag, internal gain and offset registers, and a low-pass digital FIR filter make the AD7762 a compact, highly integrated data acquisition device requiring minimal peripheral component selection. In addition, the device offers programmable decimation rates, and the digital FIR filter can be adjusted if the default characteristics are not appropriate to the application. The AD7762 is ideal for applications demanding high SNR without a complex front end signal processing design.The differential input is sampled at up to 40 MSPS by an analog modulator. The modulator output is processed by a series of low-pass filters, the final filter having default or user-programmable coefficients. The sample rate, filter corner frequencies, and output word rate are set by a combination of the external clock frequency and the configuration registers of the AD7762.The reference voltage supplied to the AD7762 determines the analog input range. With a 4 V reference, the analog input range is ±3.2 V differential biased around a common mode of 2 V. This common mode biasing can be achieved using the on-chip differential amplifier, further reducing the external signal conditioning requirements.The AD7762 is available in an exposed paddle, 64-lead TQFP and is specified over the industrial temperature range from −40°C to +85°C.APPLICATIONSData acquisition systemsVibration analysisInstrumentation

The AD7765 is a high performance, 24-bit sigma-delta (Σ-Δ) analog-to-digital converter (ADC). It combines wide input bandwidth, high speed, and performance of 112 dB dynamic range at a 156 kHz output data rate. With excellent dc specifications, the converter is ideal for high speed data acquisition of ac signals where dc data is also required.Using the AD7765 eases front-end antialias filtering requirements, simplifying the design process significantly. The AD7765 offers pin-selectable decimation rates of 128× and 256×. Other features include an integrated buffer to drive the reference, as well as a fully differential amplifier to buffer and level shift the input to the modulator.An overrange alert pin indicates when an input signal exceeds the acceptable range. The addition of internal gain and internal overrange registers makes the AD7765 a compact, highly integrated data acquisition device requiring minimal peripheral components.The AD7765 also offers a low power mode, significantly reducing power dissipation without reducing the output data rate or available input bandwidth.The differential input is sampled at up to 40 MSPS by an analog modulator. The modulator output is processed by a series of low-pass filters. The external clock frequency applied to the AD7765 determines the sample rate, filter corner frequencies, and output word rate.The AD7765 device boasts a full band on-board FIR filter. The full stop-band attenuation of the filter is achieved at the Nyquist frequency. This feature offers increased protection from signals that lie above the Nyquist frequency being aliased back into the input signal bandwidth.The reference voltage supplied to the AD7765 determines the input range. With a 4.096 V reference, the analog input range is ±3.2768 V differential, biased around a common mode of 2.048 V. This common-mode biasing is achieved using the on-chip differential amplifier, further reducing the external signal conditioning requirements.The AD7765 is available in a 28-lead TSSOP package and is specified over the industrial temperature range of −40°C to +85°C.APPLICATIONSData acquisition systemsVibration analysisInstrumentation

The AD7766/AD7766-1/AD7766-2 are high performance, 24-bit, oversampled SAR analog-to-digital converters (ADCs). The AD7766/AD7766-1/AD7766-2 combine the benefits of a large dynamic range and input bandwidth, consuming 15 mW, 10.5 mW, and 8.5 mW power, respectively, and are contained in a 16-lead TSSOP package.Ideal for ultralow power data acquisition (such as PCI- and USBbased systems), the AD7766/AD7766-1/AD7766-2 provide 24-bit resolution. The combination of exceptional SNR, wide dynamic range, and outstanding dc accuracy make the AD7766/AD7766-1/ AD7766-2 ideally suited for measuring small signal changes over a wide dynamic range. This is particularly suitable for applications where small changes on the input are measured on larger ac or dc signals. In such an application, the AD7766/AD7766-1/ AD7766-2 accurately gather both ac and dc information.The AD7766/AD7766-1/AD7766-2 include an on-board digital filter (complete with linear phase response) that acts to eliminate out-of-band noise by filtering the oversampled input voltage. The oversampled architecture also reduces front-end antialias requirements. Other features of the AD7766/AD7766-1/AD7766-2 include aSYNC/PD(synchronization/power-down) pin, allowing the synchronization of multiple AD7766/AD7766-1/AD7766-2 devices. The addition of an SDI pin provides the option of daisy chaining multiple AD7766/AD7766-1/AD7766-2 devices.The AD7766/AD7766-1/AD7766-2 operate from a 2.5 V supply using a 5 V reference. The devices operate from −40°C to +105°C.ApplicationsLow power PCI/USB data acquisition systemsLow power wireless acquisition systemsVibration analysisInstrumentationHigh precision medical acquisition

The AD7767/AD7767-1/AD7767-2 are high performance, 24-bit, oversampled SAR analog-to-digital converters (ADCs). The AD7767/AD7767-1/AD7767-2 combine the benefits of a large dynamic range and input bandwidth, consuming 15 mW, 10.5 mW, and 8.5 mW power, respectively, and are contained in a 16-lead TSSOP package.Ideal for ultralow power data acquisition (such as PCI- and USB-based systems), the AD7767/AD7767-1/AD7767-2 provide 24-bit resolution. The combination of exceptional SNR, wide dynamic range, and outstanding dc accuracy make the AD7767/AD7767-1/AD7767-2 ideally suited for measuring small signal changes over a wide dynamic range. This is particularly suitable for applications where small changes on the input are measured on larger ac or dc signals. In such an application, the AD7767/AD7767-1/AD7767-2 accurately gather both ac and dc information.The AD7767/AD7767-1/AD7767-2 include an on-board digital filter (complete with linear phase response) that acts to elimi-nate out-of-band noise by filtering the oversampled input voltage. The oversampled architecture also reduces front-end antialias requirements. Other features of the AD7767 include aSYNC/PD(synchronization/power-down) pin, allowing the synchronization of multiple AD7767 devices. The addition of an SDI pin provides the option of daisy chaining multiple AD7767 devices.The AD7767/AD7767-1/AD7767-2 operate from a 2.5 V supply using a 5 V reference. The devices operate from −40°C to +105°C.ApplicationsLow power PCI/USB data acquisition systemsLow power wireless acquisition systemsVibration analysisInstrumentationHigh precision medical acquisition

The AD7768-1 is a low power, high performance, Σ-Δ analog-to-digital converter (ADC), with a Σ-Δ modulator and digital filter for precision conversion of both ac and dc signals. The AD7768-1 is a single-channel version of the AD7768, an 8-channel, simultaneously sampling, Σ-Δ ADC. The AD7768-1 provides a single configurable and reusable data acquisition (DAQ) footprint, which establishes a new industry standard in combined ac and dc performance and enables instrumentation and industrial system designers to design across multiple measurement variants for both isolated and nonisolated applications.The AD7768-1 achieves a 108.5 dB dynamic range when using the low ripple, finite impulse response (FIR) digital filter at 256 kSPS, giving 110.8 kHz input bandwidth, combined with ±1.1 ppm integral nonlinearity (INL), ±30 µV offset error, and ±30 ppm gain error.A wider bandwidth, up to 500 kHz Nyquist (filter −3 dB point of 204 kHz), is available using the sinc5 filter, enabling a view of signals over an extended range.The AD7768-1 offers the user the flexibility to configure and optimize for input bandwidth vs. output data rate (ODR) and vs. power dissipation. The flexibility of the AD7768-1 allows dynamic analysis of a changing input signal, making the device particularly useful in general-purpose DAQ systems. The selection of one of three available power modes allows the designer to achieve required noise targets while minimizing power consumption. The design of the AD7768-1 is unique in that it becomes a reusable and flexible platform for low power dc and high performance ac measurement modules.The AD7768-1 achieves the optimum balance of dc and ac performance with excellent power efficiency. The following three operating modes allow the user to trade off the input bandwidth vs. power budgets:Fast mode offers both a sinc filter with up to 256 kSPS and 52.2 kHz of bandwidth, and 26.4 mW of power consumption, or a FIR filter with up to 256 kSPS, 110.8 kHz of bandwidth and 36.8 mW of power consumption.Median mode offers a FIR filter with up to 128 kSPS, 55.4 kHz of bandwidth and 19.7 mW of power consumption.Low power mode offers a FIR filter with up to 32 kSPS, 13.85 kHz of bandwidth and 6.75 mW of power consumption.The AD7768-1 offers extensive digital filtering capabilities that meet a wide range of system requirements. The filter options allow configuration for frequency domain measurements with tight gain error over frequency, linear phase response requirements (brick wall filter), a low latency path (sinc5 or sinc3) for use in control loop applications, and measuring dc inputs with the ability to configure the sinc3 filter to reject the line frequency of either 50 Hz or 60 Hz. All filters offer programmable decimation.A 1.024 MHz sinc5 filter path exists for users seeking an even higher ODR than is achievable using the low ripple FIR filter. This path is quantization noise limited. Therefore, it is best suited for customers requiring minimum latency for control loops or implementing custom digital filtering on an external field programmable gate array (FPGA) or digital signal processor (DSP).The filter options include the following:A low ripple FIR filter with a ±0.005 dB pass-band ripple to 102.4 kHz.A low latency sinc5 filter with up to a 1.024 MHz data rate to maximize control loop responsiveness.A low latency sinc3 filter that is fully programmable, with 50 Hz/60 Hz rejection capabilities.When using the AD7768-1, embedded analog functionality within the AD7768-1 greatly reduces the design burden over the entire application range. The precharge buffer on each analog input decreases the analog input current compared to competing products, simplifying the task of an external amplifier to drive the analog input.A full buffer input on the reference reduces the input current, providing a high impedance input for the external reference device or in buffering any reference sense resistor scenarios used in ratiometric measurements.The device operates with a 5.0 V AVDD1 − AVSS supply, a 2.0 V to 5.0 V AVDD2 − AVSS supply, and a 1.8 V to 3.3 V IOVDD − DGND supply.In low power mode, the AVDD1, AVDD2, and IOVDD supplies can run from a single 3.0 V rail.The device requires an external reference. The absolute input reference (REFIN) voltage range is 1 V to AVDD1 − AVSS.The specified operating temperature range is −40°C to +125°C. The device is housed in a 4 mm × 5 mm, 28-lead LFCSP.Note that, throughout this data sheet, multifunction pins, such as XTAL2/MCLK, are referred to either by the entire pin name or by a single function of the pin, for example, MCLK, when only that function is relevant.ApplicationsPlatform ADC to serve a superset of measurements and sensor typesSound and vibration, acoustic, and material science research and developmentControl and hardware in loop verificationCondition monitoring for predictive maintenanceElectrical test and measurementAudio testing and current and voltage measurementClinical electroencephalogram (EEG), electromyogram (EMG), and electrocardiogram (ECG) vital signs monitoringUSB-, PXI-, and Ethernet-based modular DAQChannel to channel isolated modular DAQ designs

The AD7771 is an 8-channel, simultaneous sampling analog-to-digital converter (ADC). Eight full Σ-Δ ADCs are on-chip. The AD7771 provides an ultralow input current to allow direct sensor connection. Each input channel has a programmable gain stage allowing gains of 1, 2, 4, and 8 to map lower amplitude sensor outputs into the full-scale ADC input range, maximizing the dynamic range of the signal chain. The AD7771 accepts a VREFvoltage from 1 V up to 3.6 V. The analog inputs accept unipolar (0 V to VREF) or true bipolar (±VREF/2 V) analog input signals with 3.3 V or ±1.65 V analog supply voltages, respectively. The analog inputs can be configured to accept true differential or single-ended signals to match different sensor output configurations.Each channel contains an ADC modulator and a sinc3/sinc5, low latency digital filter. A sample rate converter (SRC) is provided to allow fine resolution control over the AD7771 output data rate (ODR). This control can be used in applications where the ODR resolution is required to maintain coherency with 0.01 Hz changes in the line frequency. The SRC is programmable through the serial port interface (SPI). The AD7771 implements two different interfaces: a data output interface and SPI control interface. The ADC data output interface is dedicated to transmitting the ADC conversion results from the AD7771 to the processor. The SPI writes to and reads from the AD7771 configuration registers and for the control and reading of data from the successive approximation register (SAR) ADC. The SPI can also be configured to output the Σ-Δ conversion data.The AD7771 includes a 12-bit SAR ADC. This ADC can be used for AD7771 diagnostics without having to decommission one of the Σ-Δ ADC channels dedicated to system measurement functions. With the use of an external multiplexer, which can be controlled through the three general-purpose input/output pins (GPIOs), and signal conditioning, the SAR ADC can validate the Σ-Δ ADC measurements in applications where functional safety is required. In addition, the AD7771 SAR ADC includes an internal multiplexer to sense internal nodes.The AD7771 contains a 2.5 V reference and reference buffer. The reference has a typical temperature coefficient of ±10 ppm/°C.The AD7771 offers two modes of operation: high resolution mode and low power mode. High resolution mode provides a higher dynamic range while consuming 16.6 mW per channel; low power mode consumes only 5.25 mW per channel at a reduced dynamic range specification.The specified operating temperature range is −40°C to +105°C, although the device is operational up to +125°C.Note that throughout this data sheet, certain terms are used to refer to either the multifunction pins or a range of pins. The multifunction pins, such as DCLK0/SDO, are referred to either by the entire pin name or by a single function of the pin, for example, DCLK0, when only that function is relevant. In the case of ranges of pins, AVSSx refers to the following pins: AVSS1A, AVSS1B, AVSS2A, AVSS2B, AVSS3, and AVSS4.ApplicationsPower quality and measurement applicationsGeneral-purpose data acquisitionElectroencephalography (EEG)Industrial process control