Datasheet AD7856 (Analog Devices)

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5 V Single Supply, 8-Channel 14-Bit 285 kSPS Sampling ADC AD7856 FEATURES FUNCTIONAL BLOCK DIAGRAM Single 5␣ V Supply AVDD AGND 285 kSPS Throughput Rate Self- and System Calibration with Autocalibration on Power-Up DV ... DD AIN1 .. I/P AD7856 T/H MUX Eight Single-Ended or Four Pseudo-Differential Inputs AIN8 Low Power: 60 mW Typ 4.096V Automatic Power-Down After Conversion (2.5␣
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W Typ) REFERENCE Flexible Serial Interface: 8051/SPI™/QSPI™/
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P Compatible COMP 24-Lead DIP, SOIC and SSOP Packages DGND REFIN/REFOUT BUF APPLICATIONS CREF1 Battery-Powered Systems (Personal Digital Assistants, Medical Instruments, Mobile Communications) CHARGE REDISTRIBUTION Pen Computers DAC Instrumentation and Control Systems CLKIN High Speed Modems CREF2 SAR + ADC CONVST CONTROL CALIBRATION BUSY CAL MEMORY AND CONTROLLER SLEEP GENERAL DESCRIPTION SERIAL INTERFACE/CONTROL REGISTER
The AD7856 is a high speed, low power, 14-bit ADC that oper- ates from a single 5 V power supply. The ADC powers up with
SYNC DIN DOUT SCLK
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
PRODUCT HIGHLIGHTS
temperature and it has a number of power-down options for low 1. Single 5 V supply. power applications. 2. Automatic calibration on power-up. The AD7856 is capable of 285 kHz throughput rate. The input 3. Flexible power management options including automatic track-and-hold acquires a signal in 500 ns and features a pseudo- power-down after conversion. differential sampling scheme. The AD7856 voltage range is 0 to V 4. Operates with reference voltages from 1.2 V to V REF with straight binary output coding. Input signal range is to DD. the supply and the part is capable of converting full power sig- 5. Analog input range from 0 V to VDD. nals to 10 MHz. 6. Eight single-ended or four pseudo-differential input channels. CMOS construction ensures low power dissipation of typically 7. Self- and system calibration. 60 mW for normal operation and 5.1 mW in power-down mode at 10 kSPS throughput rate. The part is available in 24-lead, 8. Versatile serial I/O port (SPI/QSPI/8051/µP). 0.3 inch-wide dual in-line package (DIP), 24-lead small outline (SOIC) and 24-lead small shrink outline (SSOP) packages. Please see page 31 for data sheet index. SPI and QSPI are trademarks of Motorola, Inc. REV. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties
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