Analog Devices Inc.
The AD7763 high performance, 24-bit, ?-? analog-to-digitalconverter (ADC) combines wide input bandwidth and high speed with the benefits of ?-? conversion, as well as performanceof 107 dB SNR at 625 kSPS, making it ideal for high speed dataacquisition. A wide dynamic range, combined with significantly reduced antialiasing requirements, simplifies 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 AD7763 a compact, highly integrated data acquisition device requiring minimal peripheral componentselection. In addition, the device offers programmable decimation rates and a digital FIR filter, which can be user-programmed to ensure that its characteristics are tailored for the user?s application. The AD7763 is ideal for applications demanding high SNR without necessitating the design of complex, front-end signal processing.The differential input is sampled at up to 40 MSPS by an analogmodulator. 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 AD7763.The reference voltage supplied to the AD7763 determines theanalog 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 amplifiers, further reducing the external signal conditioning requirements.The AD7763 is available in an exposed paddle, 64-lead TQFP_EPand is specified over the industrial temperature range from ?40?C to +85?C.APPLICATIONS Data acquisition systems Vibration analysis Instrumentation