60 MHz, 2000 V/s, Monolithic Op Amp with Quad Low Noise Data Sheet AD844 FEATURES FUNCTIONAL BLOCK DIAGRAMS Wide bandwidth NULL 1 8 NULL AD844 60 MHz at gain of 1 IN 2 7 +V S 33 MHz at gain of 10 +IN 3 6 OUTPUT V 4 5 TZ S Slew rate: 2000 V/s 20 MHz full power bandwidth, 20 V p-p, R = 500 L TOP VIEW (Not to Scale) Fast settling: 100 ns to 0.1% (10 V step) Figure 1. 8-Lead PDIP (N) and 8-Lead CERDIP (Q) Packages Differential gain error: 0.03% at 4.4 MHz Differential phase error: 0.16 at 4.4 MHz NC 1 16 NC Low offset voltage: 150 V maximum (B Grade) OFFSETNULL 2 15 OFFSETNULL Low quiescent current: 6.5 mA IN 3 14 V+ NC 4 13 NC Available in tape and reel in accordance with +IN 5 12 OUTPUT EIA-481-A standard NC 6 11 TZ AD844 V 7 10 NC APPLICATIONS TOP VIEW NC 8 9 NC (Not to Scale) Flash ADC input amplifiers NC = NO CONNECT High speed current DAC interfaces Figure 2. 16-Lead SOIC (R) Package Video buffers and cable drivers Pulse amplifiers The AD844A and AD844B are specified for the industrial GENERAL DESCRIPTION temperature range of 40C to +85C and are available in the The AD844 is a high speed monolithic operational amplifier CERDIP (Q) package. The AD844A is also available in an 8-lead fabricated using the Analog Devices, Inc., junction isolated PDIP (N). The AD844S is specified over the military temperature complementary bipolar (CB) process. It combines high band- range of 55C to +125C. It is available in the 8-lead CERDIP width and very fast large signal response with excellent dc (Q) package. A and S grade chips and devices processed to performance. Although optimized for use in current-to-voltage MIL-STD-883B, Rev. C are also available. applications and as an inverting mode amplifier, it is also suitable for use in many noninverting applications. PRODUCT HIGHLIGHTS 1. The AD844 is a versatile, low cost component providing an The AD844 can be used in place of traditional op amps, but its current feedback architecture results in much better ac perfor- excellent combination of ac and dc performance. mance, high linearity, and an exceptionally clean pulse response. 2. It is essentially free from slew rate limitations. Rise and fall times are essentially independent of output level. This type of op amp provides a closed-loop bandwidth that is 3. The AD844 can be operated from 4.5 V to 18 V power determined primarily by the feedback resistor and is almost supplies and is capable of driving loads down to 50 , as independent of the closed-loop gain. The AD844 is free from well as driving very large capacitive loads using an external the slew rate limitations inherent in traditional op amps and network. other current-feedback op amps. Peak output rate of change can 4. The offset voltage and input bias currents of the AD844 are be over 2000 V/s for a full 20 V output step. Settling time is laser trimmed to minimize dc errors VOS drift is typically 1 typically 100 ns to 0.1%, and essentially independent of gain. V/C and bias current drift is typically 9 nA/C. The AD844 can drive 50 loads to 2.5 V with low distortion 5. The AD844 exhibits excellent differential gain and and is short-circuit protected to 80 mA. differential phase characteristics, making it suitable for a The AD844 is available in four performance grades and three variety of video applications with bandwidths up to 60 MHz. package options. In the 16-lead SOIC (RW) package, the AD844J 6. The AD844 combines low distortion, low noise, and low is specified for the commercial temperature range of 0C to 70C. drift with wide bandwidth, making it outstanding as an input amplifier for flash analog-to-digital converters (ADCs). Rev. G 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 1989-2017 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. 00897-001 00897-002AD844 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Response as an Inverting Amplifier ......................................... 12 Applications ....................................................................................... 1 Response as an I-V Converter .................................................. 13 Functional Block Diagrams ............................................................. 1 Circuit Description of the AD844 ............................................ 13 General Description ......................................................................... 1 Response as a Noninverting Amplifier .................................... 14 Product Highlights ........................................................................... 1 Noninverting Gain of 100 ......................................................... 14 Revision History ............................................................................... 2 Using the AD844 ............................................................................ 15 Specif icat ions ..................................................................................... 3 Board Layout ............................................................................... 15 Absolute Maximum Ratings ............................................................ 5 Input Impedance ........................................................................ 15 Metallization Photograph ............................................................ 5 Driving Large Capacitive Loads ............................................... 15 ESD Caution .................................................................................. 5 Settling Time ............................................................................... 15 Typical Performance Characteristics ............................................. 6 DC Error Calculation ................................................................ 16 Inverting Gain-of-1 AC Characteristics .................................... 8 Noise ............................................................................................ 16 Inverting Gain-of-10 AC Characteristics .................................. 9 Video Cable Driver Using 5 V Supplies ................................ 16 Inverting Gain-of-10 Pulse Response ...................................... 10 High Speed DAC Buffer ............................................................ 17 Noninverting Gain-of-10 AC Characteristics ........................ 11 20 MHz Variable Gain Amplifier ............................................. 17 Understanding the AD844 ............................................................ 12 Outline Dimensions ....................................................................... 19 Open-Loop Behavior ................................................................. 12 Ordering Guide .......................................................................... 20 REVISION HISTORY 5/2017Rev. F to Rev. G 1/2003Rev. D to Rev. E Change to Figure 32 ....................................................................... 14 Updated Features ............................................................................... 1 Edit to TPC 18 ................................................................................... 7 2/2009Rev. E to Rev F Edits to Figure 13 and Figure 14 ................................................... 13 Updated Format .................................................................. Universal Updated Outline Dimensions ....................................................... 15 Changes to Features Section............................................................ 1 Changes to Differential Phase Error Parameter, Table 1 ............. 3 11/2001Rev. C to Rev. D Edits to Specifications ...................................................................... 2 Changes to Figure 13 ........................................................................ 8 Changes to Figure 18 ........................................................................ 9 Edits to Absolute Maximum Ratings .............................................. 3 Changes to Figure 23 and Figure 24 ............................................. 11 Edits to Ordering Guide ................................................................... 3 Changes to Figure 42 and High Speed DAC Buffer Section ..... 17 Updated Outline Dimensions ....................................................... 19 Changes to Ordering Guide .......................................................... 20 Rev. G Page 2 of 20