AD7764

24-Bit, 312 kSPS, 109 dB Sigma-Delta ADC with On-Chip Buffers and Serial Interface AD7764 06518-001 FEATURES High performance 24-bit ∑-∆ 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 Overrange alert pin Digital gain correction registers Power-down mode Synchronization of multiple devices via SYNC pin Daisy chaining APPLICATIONS Data acquisition systems Vibration analysis Instrumentation FUNCTIONAL BLOCK DIAGRAM VOUTA– VOUTA+ VIN+ VIN– MCLK GND VINA+ VINA– DIFF VREF+ BUF MULTIBIT Σ-Δ MODULATOR RECONSTRUCTION AVDD1 AVDD2 AVDD3 AVDD4 DVDD OVERRANGE REFGND SYNC RESET/PWRDWN INTERFACE LOGIC AND OFFSET AND GAIN CORRECTION REGISTERS DECIMATION FIR FILTER ENGINE AD7764 FSO SCO SDI SDO FSI Figure 1. DEC_RATE RBIAS Table 1. Related Devices Part No. Description AD7760 2.5 MSPS, 100 dB, parallel output on-chip buffers AD7762 625 kSPS, 109 dB, parallel output on-chip buffers AD7763 625 kSPS, 109 dB, serial output, on-chip buffers AD7765 156 kSPS, 112 dB, serial output, on-chip buffers AD7766 128/64/32 kSPS, 8.5 mW, 109 dB SNR AD7767 128/64/32 kSPS, 8.5 mW, 109 dB SNR GENERAL DESCRIPTION The AD7764 is a high performance, 24-...