AD7856

a FEATURES Single 5␣ V Supply 285 kSPS Throughput Rate Self- and System Calibration with Autocalibration on Power-Up Eight Single-Ended or Four Pseudo-Differential Inputs Low Power: 60 mW Typ Automatic Power-Down After Conversion (2.5␣ ␮ W Typ) Flexible Serial Interface: 8051/SPI™/QSPI™/␮P Compatible 24-Lead DIP, SOIC and SSOP Packages APPLICATIONS Battery-Powered Systems (Personal Digital Assistants, Medical Instruments, Mobile Communications) Pen Computers Instrumentation and Control Systems High Speed Modems 5 V Single Supply, 8-Channel 14-Bit 285 kSPS Sampling ADC AD7856 FUNCTIONAL BLOCK DIAGRAM AVDD AGND DVDD AIN1 AIN8 .... I/P MUX T/H AD7856 ..... 4.096V REFERENCE COMP REFIN/REFOUT CREF1 CHARGE REDISTRIBUTION DAC CLKIN CREF2 CAL CALIBRATION MEMORY AND CONTROLLER SAR + ADC CONTROL CONVST BUSY SLEEP BUF DGND GENERAL DESCRIPTION The AD7856 is a high speed, low power, 14-bit ADC that operates from a single 5 V power supply. The ADC powers up with a set of default conditions at which time it can be operated as a read only ADC. The ADC contains self-calibration and system calibration options to ensure accurate operation over time and temperature and it has a number of power-down options for low power applications. The AD7856 is capable of 285 kHz throughput rate. The input track-and-hold acquires a signal in 500 ns and features a pseudodifferential sampling scheme. The AD7856 voltage range is 0 to VREF with straight binary output coding. Input signal range is to the ...