AD7764 24-Bit, 312 kSPS, 109 dB Sigma Delta ADC with On-Chip Buffers and Serial Interface

The AD7764 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 109 dB dynamic range at a 312 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. Data acquisition systems Vibration analysis Instrumentation

Using the AD7764 eases the front-end antialias filtering requirements, simplifying the design process significantly. The AD7764 offers pin-selectable decimation rates of 64×, 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 has exceeded the acceptable range. The addition of internal gain and internal overrange registers makes the AD7764 a compact, highly integrated data acquisition device requiring minimal peripheral components.

The AD7764 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 AD7764 determines the sample rate, filter corner frequencies, and output word rate.

The AD7764 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 AD7764 determines the input range. With a 4 V reference, the analog input range is ±3.2768 V differential, biased around a common mode of 2.048 V. This common-mode biasing can be achieved using the on-chip differential amplifier, further reducing the external signal conditioning requirements.

The AD7764 is available in a 28-lead TSSOP package and is specified over the industrial temperature range of −40°C to +85°C.

Applications

Features and Benefits
  • High performance 24-bit Σ-Δ ADC
  • 115 dB dynamic range at 78 kHz output data rate
  • 109 dB dynamic range at 312 kHz output data rate
  • 312 kHz maximum fully filtered output word rate
  • Pin-selectable oversampling rate (64×, 128×, and 256×)
  • Low power mode
  • Flexible SPI
  • Fully differential modulator input
  • On-chip differential amplifier for signal buffering
  • On-chip reference buffer
  • Full band low-pass finite impulse response (FIR) filter
  • See data sheet for additional features
Analog to Digital Converters
Data Sheets
Documentnote
AD7764: 24-Bit, 312 kSPS, 109 dB Sigma-Delta ADC with On-Chip Buffers and Serial Interface Data Sheet (Rev. A)PDF 1274 kB
Order Information
Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
AD7764BRUZ Production28 ld TSSOP (4.4mm)OTH 50-40 to 85C12.7210.1Y
AD7764BRUZ-REEL7 Production28 ld TSSOP (4.4mm)REEL 1000-40 to 85C010.1Y
Evaluation Boards
Part NumberDescriptionPriceRoHS
EVAL-AD7764EDZEvaluation Board59Y
EVAL-AD7765EDZEvaluation Board59Y
EVAL-CED1ZEvaluation Board249Y
Reference Materials
AD7764: 24-Bit, 312 kSPS, 109 dB Sigma-Delta ADC with On-Chip Buffers and Serial Interface Data Sheet (Rev. A) ad7764
MS-2210:高速ADC的电源设计 ad9861