AD7768-1 Datasheet

• ADC for single-channel low power, platform DAQ designs
• Wide bandwidth
  • Sinc filter bandwidth range: DC to 204 kHz
  • Low ripple FIR bandwidth range: DC to 110.8 kHz
• Precision ac and dc performance
  • 108.5 dB dynamic range typical
  • −120 dB THD
  • ±1.1 ppm of FSR INL, ±30 µV offset error, ±30 ppm of FSR gain error
• Programmable ODR, filter type, and latency
  • ODR values up to 1024 kSPS
• Linear phase digital filter options
  • Low ripple FIR filter: ±0.005 dB maximum pass-band ripple, dc to 102.4 kHz
  • Low latency sinc5 filter
  • Low latency sinc3 filter enabling 50 Hz/60 Hz rejection
  • Programmable FIR filter option
• Programmable power consumption and bandwidth
  • Fast, highest speed
    • 52.224 kHz bandwidth, 26.4 mW (sinc5 filter)
    • 110.8 kHz bandwidth, 36.8 mW (FIR filter)
  • Median, half speed: 55.4 kHz bandwidth, 19.7 mW (FIR filter)
  • Low power, low speed: 13.9 kHz bandwidth, 6.75 mW (FIR filter)
• Power supply
  • AVDD1 − AVSS = 5.0 V typical
  • AVDD2 − AVSS = 2.0 V to 5.0 V typical
  • Analog supplies can run from split supply (true bipolar)
  • IOVDD − DGND = 1.8 V to 3.3 V typical
• Low power mode can run from single 3.0 V supply
• Pin control or SPI interface configurable
• Suite of diagnostic check mechanisms
  • Temperature, interface CRC, and memory map CRC
• Package: 28-lead, 4 mm × 5 mm, LFCSP
• Temperature range: −40°C to +125°C

• Platform ADC to serve a superset of measurements and sensor types
• Sound and vibration, acoustic, and material science research and development
• Control and hardware in loop verification
• Condition monitoring for predictive maintenance
• Electrical test and measurement
• Audio testing and current and voltage measurement
• Clinical electroencephalogram (EEG), electromyogram (EMG), and electrocardiogram (ECG) vital signs monitoring
• USB-, PXI-, and Ethernet-based modular DAQ
• Channel to channel isolated modular DAQ designs

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.