Datasheet AD7858, AD7858L (Analog Devices)

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3 V to 5 V Single Supply, 200 kSPS 8-Channel, 12-Bit Sampling ADC AD7858/AD7858L FEATURES FUNCTIONAL BLOCK DIAGRAM Specified for VDD of 3 V to 5.5 V AD7858—200 kSPS; AD7858L—100 kSPS AVDD AGND System and Self-Calibration with Autocalibration on Power-Up AIN1 AD7858/ Eight Single-Ended or Four Pseudo-Differential Inputs I/P T/H MUX AD7858L Low Power AIN8 DVDD AD7858: 12 mW (VDD = 3 V) 2.5V AD7858L: 4.5 mW (V REFERENCE DD = 3 V) COMP Automatic Power-Down After Conversion (25
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W) Flexible Serial Interface: REF BUF DGND IN/REFOUT 8051/SPI™/QSPI™/
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P Compatible C 24-Lead DIP, SOIC, and SSOP Packages REF1 CHARGE APPLICATIONS REDISTRIBUTION DAC Battery-Powered Systems (Personal Digital Assistants, CLKIN Medical Instruments, Mobile Communications) CREF2 SAR AND ADC CONVST Pen Computers CALIBRATION CONTROL BUSY Instrumentation and Control Systems MEMORY AND CAL CONTROLLER SLEEP High-Speed Modems GENERAL DESCRIPTION SERIAL INTERFACE/CONTROL REGISTER
The AD7858/AD7858L are high-speed, low-power, 12-bit ADCs that operate from a single 3 V or 5 V power supply, the
SYNC DIN DOUT SCLK
AD7858 being optimized for speed and the AD7858L for low power. 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 en-
PRODUCT HIGHLIGHTS
sure accurate operation over time and temperature and have a 1. Specified for 3 V and 5 V supplies. number of power-down options for low-power applications. 2. Automatic calibration on power-up. The part powers up with a set of default conditions and can 3. Flexible power management options including automatic operate as a read-only ADC. power-down after conversion. The AD7858 is capable of 200 kHz throughput rate while the 4. Operates with reference voltages from 1.2 V to V AD7858L is capable of 100 kHz throughput rate. The input DD. track-and-hold acquires a signal in 500 ns and features a 5. Analog input range from 0 V to VDD. pseudo-differential sampling scheme. The AD7858/AD7858L 6. Eight single-ended or four pseudo-differential input channels. voltage range is 0 to VREF with straight binary output coding. 7. System and self-calibration. Input signal range is to the supply and the part is capable of con- verting full power signals to 100 kHz. 8. Versatile serial I/O port (SPI/QSPI/8051/µP). CMOS construction ensures low power dissipation of typically 9. Lower power version AD7858L. 4.5 mW for normal operation and 1.15 mW in power-down mode with a throughput rate of 10 kSPS (VDD = 3 V). The part is available in 24-lead, 0.3 inch-wide dual-in-line package (DIP), 24-lead small outline (SOIC), and 24-lead small shrink outline (SSOP) packages. See page 31 for data sheet index. SPI and QSPI are trademarks of Motorola, Inc. REV. B Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its
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