AD7674

18-Bit, 2.5 LSB INL, 570 kSPS SAR ADC AD7679 FEATURES 18-bit resolution with no missing codes No pipeline delay (SAR architecture) Differential input range: ±VREF (VREF up to 5 V) Throughput: 570 kSPS INL: ±2.5 LSB max (±9.5 ppm of full scale) Dynamic range : 103 dB typ (VREF = 5 V) S/(N+D): 100 dB typ @ 2 kHz (VREF = 5 V) Parallel (18-,16-, or 8-bit bus) and serial 5 V/3 V interface SPI®/QSPI™/MICROWIRE™/DSP compatible On-board reference buffer Single 5 V supply operation Power dissipation: 76 mW @ 500 kSPS 150 µW @ 1 kSPS 48-lead LQFP or 48-lead LFCSP package Pin-to-pin compatible upgrade of AD7674/AD7676/AD7678 FUNCTIONAL BLOCK DIAGRAM PDBUF AGND AVDD REFBUFIN IN+ IN– SWITCHED CAP DAC PARALLEL INTERFACE CLOCK PD RESET CONTROL LOGIC AND CALIBRATION CIRCUITRY REF REFGND DVDD DGND OVDD SERIAL PORT 18 OGND AD7679 D[17:0] BUSY RD CS MODE0 MODE1 CNVST 03085–0–001 Figure 1. Functional Block Diagram APPLICATIONS CT scanners High dynamic data acquisition Geophone and hydrophone sensors Σ-∆ replacement (low power, multichannel) Instrumentation Spectrum analysis Medical instruments Table 1. PulSAR Selection Type/kSPS PseudoDifferential True Bipolar True Differential 18-Bit Multichannel/ Simultaneous 100–250 AD7651 AD7660/AD7661 AD7663 AD7675 AD7678 500–570 AD7650/AD7652 AD7664/AD7666 AD7665 AD7676 AD7679 AD7654 AD7655 800– 1000 AD7653 AD7667 AD7671 AD7677 AD7674 GENERAL DESCRIPTION The AD7679 is an 18-bit, 570 kSPS, charge redistribution SAR, fully differential analog-to-dig...