General-Purpose, Low Cost, DC-Coupled VGA Data Sheet AD8337 FEATURES GENERAL DESCRIPTION Low noise The AD8337 is a low noise, single-ended, linear-in-dB, general- Voltage noise = 2.2 nV/Hz purpose, variable gain amplifier (VGA) usable at frequencies Current noise = 4.8 pA/Hz (positive input) from dc to 100 MHz the 3 dB bandwidth is 280 MHz. Wide bandwidth (3 dB) = 280 MHz Excellent bandwidth uniformity across the entire gain range Nominal gain range: 0 dB to 24 dB (preamp gain = 6 dB) and low output referred noise make the AD8337 ideal for Gain scaling: 19.7 dB/V gain trim applications and for driving high speed analog-to- DC-coupled digital converters (ADCs). Single-ended input and output Excellent dc characteristics combined with high speed make the High speed uncommitted op amp input AD8337 particularly suited for industrial ultrasound, PET Supplies: +5 V, 2.5 V, or 5 V scanners, and video applications. Dual-supply operation enables Low power: 78 mW with 2.5 V supplies gain control of negative going pulses, such as those generated by photodiodes or photomultiplier tubes. APPLICATIONS Gain trim The AD8337 uses the Analog Devices, Inc., exclusive X-AMP PET scanners architecture with 24 dB gain range scaled to 19.7 dB/V, High performance AGC systems referenced to VCOM. I/Q signal processing The AD8337 preamplifier is configured in a current feedback Video architecture optimized for gains of 6 dB to 24 dB. The AD8337 Industrial and medical ultrasound is characterized by a noninverting preamplifier gain of 2 using a Radar receivers pair of 100 resistors. The attenuator has a range of 24 dB, and the output amplifier has a fixed gain of 8 (18.06 dB). The lowest nominal gain range is 0 dB to 24 dB and can be shifted up or down by adjusting the preamplifier gain. Series connected AD8337 devices provide larger gain ranges, interstage filtering to suppress noise and distortion, and nulling of offset voltages. FUNCTIONAL BLOCK DIAGRAM GAIN CONTROL GAIN INTERFACE EIGHT SECTIONS PREAMP INPP 18dB VOUT INPN PRAO VCOM Figure 1 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 20052016 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. 05575-001AD8337 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Single-Supply Operation and AC Coupling ........................... 19 Applications ....................................................................................... 1 Noise ............................................................................................ 19 General Description ......................................................................... 1 Applications Information .............................................................. 20 Functional Block Diagram .............................................................. 1 Preamplifier Connections ......................................................... 20 Revision History ............................................................................... 2 Driving Capacitive Loads .......................................................... 20 Specif icat ions ..................................................................................... 3 Gain Control Considerations ................................................... 21 Absolute Maximum Ratings ............................................................ 5 Thermal Considerations ............................................................ 22 ESD Caution .................................................................................. 5 PSI () ......................................................................................... 22 Pin Configuration and Function Descriptions ............................. 6 Board Layout ............................................................................... 22 Typical Performance Characteristics ............................................. 7 Evaluation Boards ........................................................................... 23 Test Circuits ..................................................................................... 14 Circuit Options ........................................................................... 24 Theory of Operation ...................................................................... 18 Output Protection ...................................................................... 24 O ver vie w ...................................................................................... 18 Measurement Setup.................................................................... 25 Preamplifier ................................................................................. 18 Board Layout Considerations ................................................... 25 VGA .............................................................................................. 18 Outline Dimensions ....................................................................... 28 Gain Control ............................................................................... 18 Ordering Guide .......................................................................... 28 Output Stage ................................................................................ 19 Attenuator .................................................................................... 19 REVISION HISTORY 10/2016Rev. C to Rev. D 2/2007Rev. A to Rev. B Changes to General Description Section and Figure 1 ............... 1 Changes to Figure 30, Figure 31, and Figure 32 ......................... 11 Change to Input Voltage Noise Parameter, Table 1 ...................... 3 Changes to Single-Supply Operation and Changes to Figure 2 .......................................................................... 6 AC Coupling Section ..................................................................... 19 Changes to Typical Performance Characteristics Section ........... 7 Moved Noise Section to Page ........................................................ 19 Changes to Preamplifier Section .................................................. 18 Changes to Ordering Guide .......................................................... 24 Deleted Bill of Materials Section, Table 5, and Table 6 6/2006Rev. 0 to Rev. A Renumbered Sequentially .............................................................. 27 Updated Format .................................................................. Universal Deleted Table 7 ................................................................................ 28 Changes to Table 3 ............................................................................. 6 Updated Outline Dimensions ....................................................... 28 Changes to Figure 22, Figure 25, and Figure 26 ......................... 10 Changes to Ordering Guide .......................................................... 28 Changes to Figure 39 and Figure 40............................................. 13 Changes to Figure 74 and Figure 75............................................. 23 9/2008Rev. B to Rev. C Updated Outline Dimensions ....................................................... 25 Changes to Table 1 ............................................................................ 3 Changes to Ordering Guide .......................................................... 25 Added Exposed Pad Note to Figure 2 and Table 3 ....................... 6 9/2005Revision 0: Initial Version Changes to Figure 49 ...................................................................... 14 Changes to Evaluation Boards Section ........................................ 23 Changes to Circuit Options Section ............................................. 24 Changes to Output Protection Section ........................................ 24 Changes to Measurement Setup Section ..................................... 25 Changes to Board Layout Considerations Section ..................... 25 Changes to Bill of Materials Section ............................................ 27 Updated Outline Dimensions, Changes to Ordering Guide .... 29 Rev. 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