16-Bit, 5 MSPS PulSAR Differential ADC Data Sheet AD7961 FEATURES FUNCTIONAL BLOCK DIAGRAM REFIN REF VCM VDD1 VDD2 VIO Throughput: 5 MSPS 16-bit resolution with no missing codes EN0 Excellent ac and dc performance EN1 2 CLOCK Dynamic range: 96 dB EN2 LOGIC EN3 SNR: 95.5 dB IN+ CAP CNV+, CNV THD: 116 dB DAC IN INL: 0.2 LSB (typical), 0.55 LSB (maximum) D+, D DNL: 0.14 LSB (typical), 0.25 LSB (maximum) SERIAL SAR DCO+, DCO LVDS True differential analog input voltage range: 4.096 V or 5 V CLK+, CLK AD7961 Low power dissipation GND 46.5 mW at 5 MSPS with external reference buffer (echoed clock mode) Figure 1. 64.5 mW at 5 MSPS with internal reference buffer GENERAL DESCRIPTION (echoed clock mode) The AD7961 is a 16-bit, 5 MSPS, charge redistribution successive 39 mW at 5 MSPS with external reference buffer approximation (SAR), analog-to-digital converter (ADC). The (self clocked mode, CNV in CMOS mode) SAR architecture allows unmatched performance both in noise SAR architecture and in linearity. The AD7961 contains a low power, high speed, No latency/pipeline delay 16-bit sampling ADC, an internal conversion clock, and an External reference options: 2.048 V buffered to 4.096 V (internal internal reference buffer. On the CNV edge, the AD7961 reference buffer), 4.096 V, and 5 V samples the voltage difference between the IN+ and IN pins. Serial LVDS interface The voltages on these pins swing in opposite phase between 0 V Self clocked mode and 4.096 V and between 0 V and 5 V. The reference voltage is Echoed clock mode applied to the part externally. All conversion results are available LVDS or CMOS option for conversion control (CNV signal) on a single LVDS self clocked or echoed clock serial interface. Operating temperature range of 40C to +85C The AD7961 is available in a 32-lead LFCSP (QFN) with 32-lead, 5 mm 5 mm LFCSP (QFN) operation specified from 40C to +85C. APPLICATIONS Table 1. Fast PulSAR ADC Selection Digital imaging systems 1 MSPS to 2 MSPS to 5 MSPS Digital X-rays Input Type <2 MSPS 3 MSPS to 6 MSPS 10 MSPS Computed tomography Pseudo- AD7653 AD7985 IR cameras Differential, AD7667 MRI gradient control 16-Bit AD7980 High speed data acquisition AD7983 Spectroscopy True Bipolar, AD7671 Test equipment 16-Bit 1 Differential, AD7677 AD7621 AD7625 AD7626 16-Bit AD7623 AD7622 AD7961 1 Differential, AD7643 AD7641 AD7960 18-Bit AD7982 AD7986 AD7984 1 Antiphase. Rev. B Document Feedback 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 One Technology Way, P.O. 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Technical Support www.analog.com 10888-001AD7961 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Circuit Information .................................................................... 14 Applications ....................................................................................... 1 Converter Information .............................................................. 14 Functional Block Diagram .............................................................. 1 Transfer Function ....................................................................... 15 General Description ......................................................................... 1 Analog Inputs ............................................................................. 15 Revision History ............................................................................... 2 Typical Applications ................................................................... 16 Specif icat ions ..................................................................................... 3 Voltage Reference Options ........................................................ 17 Timing Specifications .................................................................. 5 Power Supply ............................................................................... 18 Absolute Maximum Ratings ............................................................ 7 Digital Interface .............................................................................. 19 Thermal Resistance ...................................................................... 7 Conversion Control ................................................................... 19 ESD Caution .................................................................................. 7 Applications Information .............................................................. 22 Pin Configuration and Function Descriptions ............................. 8 Layout .......................................................................................... 22 Typical Performance Characteristics ............................................. 9 Evaluating AD7961 Performance ............................................. 22 Terminology .................................................................................... 13 Outline Dimensions ....................................................................... 23 Theory of Operation ...................................................................... 14 Ordering Guide .......................................................................... 23 REVISION HISTORY 3/14Rev. A to Rev. B Changes to Table 4 ............................................................................ 7 Deleted Table 6 Renumbered Sequentially .................................. 7 Changes to Figure 19 ...................................................................... 11 11/13Rev. 0 to Rev. A Change to Table 1 ............................................................................. 1 Changes to Table 2 ............................................................................ 3 Change to Table 3 ............................................................................. 5 Changes to Table 4 ............................................................................ 7 Added Table 6 Renumbered Sequentially .................................... 7 Change to Figure 4 ........................................................................... 8 Changes to Figure 32 ...................................................................... 16 Change to Voltage Reference Options Section ........................... 17 8/13Revision 0: Initial Version Rev. B Page 2 of 24