4-Channel, 200 kSPS 12-Bit ADC with Sequencer in 16-Lead TSSOP Data Sheet AD7923 FEATURES FUNCTIONAL BLOCK DIAGRAM Fast throughput rate: 200 kSPS AV DD Specified for AVDD of 2.7 V to 5.25 V REF IN Low power 3.6 mW max at 200 kSPS with 3 V supply V 0 IN T/H 7.5 mW max at 200 kSPS with 5 V supply 12-BIT SUCCESSIVE 4 (single-ended) inputs with sequencer APPROXIMATION Wide input bandwidth ADC I/P 70 dB Min SNR at 50 kHz input frequency MUX Flexible power/serial clock speed management No pipeline delays TM High speed serial interface SPI -/QSPI -/ V 3 TM IN MICROWIRE -/DSP-compatible SCLK Shutdown mode: 0.5 A max DOUT 16-lead TSSOP package SEQUENCER CONTROL LOGIC DIN Qualified for automotive applications CS AD7923 GENERAL DESCRIPTION V DRIVE The AD7923 is a 12-bit, high speed, low power, 4-channel, suc- GND cessive approximation (SAR) ADC. It operates from a single Figure 1. 2.7 V to 5.25 V power supply and features throughput rates up to PRODUCT HIGHLIGHTS 200 kSPS. It contains a low noise, wide bandwidth track-and-hold 1. High Throughput with Low Power Consumption. amplifier that can handle input frequencies in excess of 8 MHz. The AD7923 offers up to 200 kSPS throughput rates. At the The conversion process and data acquisition are controlled by maximum throughput rate with 3 V supplies, the AD7923 CS and the serial clock, allowing the device to easily interface dissipates just 3.6 mW of power. with microprocessors or DSPs. The input signal is sampled on 2. Four Single-Ended Inputs with a Channel Sequencer. CS the falling edge of the conversion is also initiated at this 3. Single-Supply Operation with V Function. DRIVE point. The V function allows the serial interface to connect DRIVE directly to either 3 V or 5 V processor systems independent The AD7923 uses advanced design techniques to achieve very low power dissipation at maximum throughput rates. At of AVDD. maximum throughput rates, it consumes 1.2 mA maximum 4. Flexible Power/Serial Clock Speed Management. with 3 V supplies and 1.5 mA maximum with 5 V supplies. The conversion rate is determined by the serial clock, allowing the conversion time to be reduced through the Through the configuration of the control register, the analog serial clock speed increase. The part also features various input range can be selected as 0 V to REF or 0 V to 2 REF , IN IN shutdown modes to maximize power efficiency at lower with either straight binary or twos complement output coding. throughput rates. Current consumption is 0.5 A The AD7923 features four single-ended analog inputs with a maximum when in full shutdown. channel sequencer to allow a preprogrammed selection of channels to be converted sequentially. 5. No Pipeline Delay. The part features a SAR ADC with accurate control of the The conversion time for the AD7923 is determined by the serial sampling instant via a CS input and once off conversion clock, SCLK, frequency, since this is used as the master clock to control. control the conversion. The conversion time can be as short as 800 ns with a 20 MHz SCLK. Rev. D 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. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 20022013 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. 03086-001AD7923 Data Sheet TABLE OF CONTENTS Specifications ..................................................................................... 3 ADC Transfer Function ............................................................. 15 Timing Specifications ....................................................................... 5 Typical Connection Diagram ................................................... 16 Absolute Maximum Ratings ............................................................ 6 Modes of Operation ................................................................... 17 ESD Caution .................................................................................. 6 Powering Up the AD7923 ......................................................... 18 Pin Configuration and Function Description .............................. 7 Power vs. Throughput Rate ....................................................... 19 Typical Performance Characteristics ............................................. 8 Serial Interface ............................................................................ 20 Terminology .................................................................................... 10 Microprocessor Interfacing ....................................................... 21 Control Register Descriptions ...................................................... 12 Application Hints ........................................................................... 23 Sequencer Operation ................................................................. 13 Grounding and Layout .............................................................. 23 Theory of Operation ...................................................................... 14 Outline Dimensions ....................................................................... 24 Circuit Information .................................................................... 14 Ordering Guide .......................................................................... 24 Converter Operation .................................................................. 14 Automotive Products ................................................................. 24 REVISION HISTORY 6/13Rev. C to Rev. D Deleted Evaluating the AD7923 Performance Section .............. 23 Changes to Ordering Guide .......................................................... 24 5/11Rev. B to Rev. C Changes to Features Section............................................................ 1 Updated Outline Dimensions ....................................................... 24 Changes to Ordering Guide .......................................................... 24 Added to Automotive Products Section ...................................... 24 12/08Rev. A to Rev. B Changes to ESD Parameter, Table 3 ............................................... 6 Changes to Ordering Guide .......................................................... 24 8/05Rev. 0 to Rev. A Update Format .................................................................... Universal Change to Table 1 ............................................................................. 3 Change to Table 3 ............................................................................. 6 Change to Reference Section......................................................... 16 Changes to Ordering Guide .......................................................... 24 11/02Revision 0: Initial Version Rev. D Page 2 of 24