IC AMP DIFF LDIST LP 95MA 8SOIC

AD8138ARZ

Manufacturer Part NumberAD8138ARZ
DescriptionIC AMP DIFF LDIST LP 95MA 8SOIC
ManufacturerAnalog Devices Inc
TypeADC Driver
AD8138ARZ datasheet
 


Specifications of AD8138ARZ

Design ResourcesDC-Coupled, Single-Ended-to-Differential Conversion Using AD8138 and AD7352 (CN0040) DC-Coupled, Single-Ended-to-Differential Conversion Using AD8138 and AD7356 (CN0041) DC-Coupled, Single-Ended-to-Differential Conversion Using AD8138 and AD7357 (CN0061)ApplicationsData Acquisition
Mounting TypeSurface MountPackage / Case8-SOIC (3.9mm Width)
Number Of Channels1Number Of Elements1
Power Supply RequirementSingle/DualCommon Mode Rejection Ratio70dB
Voltage Gain Db0.028dBInput Resistance6@5VMohm
Input Offset Voltage2.5@5VmVInput Bias Current7@5VnA
Single Supply Voltage (typ)3/5/9VDual Supply Voltage (typ)±3/±5V
Power Supply Rejection Ratio70dBPower Dissipation550mW
Rail/rail I/o TypeNoSingle Supply Voltage (min)2.7V
Single Supply Voltage (max)11VDual Supply Voltage (min)±1.4V
Dual Supply Voltage (max)±5.5VOperating Temp Range-40C to 85C
Operating Temperature ClassificationIndustrialMountingSurface Mount
Pin Count8Package TypeSOIC N
No. Of Amplifiers1Gain Db Max1.0045dB
Bandwidth320MHzSlew Rate1150V/µs
Supply Voltage Range2.7V To 11V, ± 1.4V To ± 5.5VSupply Current20mA
Rohs CompliantYesLead Free Status / RoHS StatusLead free / RoHS Compliant
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FEATURES
Easy to use, single-ended-to-differential conversion
Adjustable output common-mode voltage
Externally adjustable gain
Low harmonic distortion
−94 dBc SFDR @ 5 MHz
−85 dBc SFDR @ 20 MHz
−3 dB bandwidth of 320 MHz, G = +1
Fast settling to 0.01% of 16 ns
Slew rate 1150 V/μs
Fast overdrive recovery of 4 ns
Low input voltage noise of 5 nV/√Hz
1 mV typical offset voltage
Wide supply range +3 V to ±5 V
Low power 90 mW on 5 V
0.1 dB gain flatness to 40 MHz
Available in 8-Lead SOIC and MSOP packages
APPLICATIONS
ADC drivers
Single-ended-to-differential converters
IF and baseband gain blocks
Differential buffers
Line drivers
GENERAL DESCRIPTION
The AD8138 is a major advancement over op amps for
differential signal processing. The AD8138 can be used as a
single-ended-to-differential amplifier or as a differential-to-
differential amplifier. The AD8138 is as easy to use as an op
amp and greatly simplifies differential signal amplification and
driving. Manufactured on ADI’s proprietary XFCB bipolar
process, the AD8138 has a −3 dB bandwidth of 320 MHz and
delivers a differential signal with the lowest harmonic distortion
available in a differential amplifier. The AD8138 has a unique
internal feedback feature that provides balanced output gain
and phase matching, suppressing even order harmonics. The
internal feed-back circuit also minimizes any gain error that
would be associated with the mismatches in the external gain
setting resistors.
The AD8138’s differential output helps balance the input to
differential ADCs, maximizing the performance of the ADC.
Rev. F
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
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
Low Distortion
Differential ADC Driver
PIN CONFIGURATION
–IN
1
8
V
2
7
OCM
V+
3
6
+OUT
4
AD8138
5
NC = NO CONNECT
Figure 1.
TYPICAL APPLICATION CIRCUIT
5V
499Ω
499Ω
V
+
IN
AIN
V
OCM
AD8138
499Ω
AIN
AVSS
499Ω
Figure 2.
The AD8138 eliminates the need for a transformer with high
performance ADCs, preserving the low frequency and dc infor-
mation. The common-mode level of the differential output is
adjustable by a voltage on the V
pin, easily level-shifting the
OCM
input signals for driving single-supply ADCs. Fast overload
recovery preserves sampling accuracy.
The AD8138 distortion performance makes it an ideal ADC
driver for communication systems, with distortion performance
good enough to drive state-of-the-art 10-bit to 16-bit converters
at high frequencies. The AD8138’s high bandwidth and IP3 also
make it appropriate for use as a gain block in IF and baseband
signal chains. The AD8138 offset and dynamic performance
makes it well suited for a wide variety of signal processing and
data acquisition applications.
The AD8138 is available in both SOIC and MSOP packages for
operation over −40°C to +85°C temperatures.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
©2006 Analog Devices, Inc. All rights reserved.
AD8138
+IN
NC
V–
–OUT
5V
AVDD
DVDD
DIGITAL
ADC
OUTPUTS
V
REF
www.analog.com

AD8138ARZ Summary of contents

  • Page 1

    FEATURES Easy to use, single-ended-to-differential conversion Adjustable output common-mode voltage Externally adjustable gain Low harmonic distortion −94 dBc SFDR @ 5 MHz −85 dBc SFDR @ 20 MHz −3 dB bandwidth of 320 MHz Fast settling to ...

  • Page 2

    AD8138 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Pin Configuration............................................................................. 1 Typical Application Circuit ............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 ±D to ±OUT Specifications...................................................... ±OUT Specifications ..................................................... 4 OCM ...

  • Page 3

    SPECIFICATIONS ±D to ±OUT SPECIFICATIONS IN At 25° ± + OCM specifications refer to single-ended input and differential outputs, unless otherwise noted. Table 1. Parameter DYNAMIC PERFORMANCE −3 dB Small ...

  • Page 4

    AD8138 V to ±OUT SPECIFICATIONS OCM At 25° ± + OCM specifications refer to single-ended input and differential outputs, unless otherwise noted. Table 2. Parameter DYNAMIC PERFORMANCE −3 dB Bandwidth ...

  • Page 5

    SPECIFICATIONS IN At 25° OCM specifications refer to single-ended input and differential output, unless otherwise noted. Table 3. Parameter DYNAMIC PERFORMANCE −3 dB Small ...

  • Page 6

    AD8138 V TO ±OUT SPECIFICATIONS OCM At 25° OCM specifications refer to single-ended input and differential output, unless otherwise noted. Table 4. Parameter DYNAMIC PERFORMANCE −3 dB ...

  • Page 7

    ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Supply Voltage V OCM Internal Power Dissipation Operating Temperature Range Storage Temperature Range Lead Temperature (Soldering 10 sec) Junction Temperature Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the ...

  • Page 8

    AD8138 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 7. Pin Function Descriptions Pin No. Mnemonic Description 1 −IN Negative Input Summing Node Voltage applied to this pin sets the common-mode output voltage with a ratio of 1:1. For example, ...

  • Page 9

    TYPICAL PERFORMANCE CHARACTERISTICS Unless otherwise noted, Gain = ±5V S –3 –6 – FREQUENCY (MHz) Figure 5. Small Signal Frequency Response ...

  • Page 10

    AD8138 – p-p OUT 800Ω L –60 –70 HD2 (V = +5V) S –80 HD2 (V S –90 –100 HD3 (V = +5V) S –110 HD3 (V = ±5V) S –120 ...

  • Page 11

    p-p OUT, dm –70 HD2 (F = 20MHz) –80 HD3 (F = 20MHz) –90 HD2 (F = 5MHz) –100 HD3 (F = 5MHz) –110 200 600 1000 1400 R (Ω) LOAD Figure ...

  • Page 12

    AD8138 V = ± +5V S 400mV Figure 23. Large Signal Transient Response C = 0pF 1pF F 400mV Figure 24. Large Signal Transient Response 200µV V OUT +DIN 1V Figure 25. ...

  • Page 13

    p-p IN –30 – ±5V S –50 – +5V S – 100 FREQUENCY (MHz) Figure 29. Output Balance Error vs. Frequency (See Figure 41) –10 ΔV /ΔV OUT ...

  • Page 14

    AD8138 + ± –3 –6 – FREQUENCY (MHz) Figure 35. V Frequency Response OCM V = ± –1V TO +1V OCM 400mV Figure 36. V Transient ...

  • Page 15

    TEST CIRCUITS R = 499Ω 499Ω G 49.9Ω AD8138 R = 499Ω G 24.9Ω 499Ω F Figure 39. Basic Test Circuit 499Ω 499Ω 24.9Ω 49.9Ω AD8138 24.9Ω 499Ω 24.9Ω 499Ω Figure 40. Test Circuit for ...

  • Page 16

    AD8138 OPERATIONAL DESCRIPTION DEFINITION OF TERMS +IN –OUT + AD8138 OCM –D IN –IN +OUT Figure 42. Circuit Definitions Differential voltage refers to the difference between ...

  • Page 17

    THEORY OF OPERATION The AD8138 differs from conventional op amps in that it has two outputs whose voltages move in opposite directions. Like an op amp, it relies on high open-loop gain and negative feedback to force these outputs to ...

  • Page 18

    AD8138 When using the AD8138 in gain configurations where one feedback network is unequal the other network, there is a differential output noise due to input-referred voltage in the ...

  • Page 19

    LAYOUT, GROUNDING, AND BYPASSING As a high speed part, the AD8138 is sensitive to the PCB environment in which it has to operate. Realizing its superior specifications requires attention to various details of good high speed PCB design. The first ...

  • Page 20

    AD8138 BALANCED TRANSFORMER DRIVER Transformers are among the oldest devices used to perform a single-ended-to-differential conversion (and vice versa). Trans- formers can also perform the additional functions of galvanic isolation, step-up or step-down of voltages, and impedance transformation. For these ...

  • Page 21

    HIGH PERFORMANCE ADC DRIVING The circuit in Figure 46 shows a simplified front-end connection for an AD8138 driving an AD9224, a 12-bit, 40 MSPS ADC. The ADC works best when driven differentially, which minimizes its distortion. The AD8138 eliminates the ...

  • Page 22

    AD8138 3 V OPERATION The circuit in Figure 47 shows a simplified front-end connection for an AD8138 driving an AD9203, a 10-bit, 40 MSPS ADC that is specified to work on a single 3 V supply. The ADC works best ...

  • Page 23

    ... AD8138AR-REEL7 −40°C to +85°C 1 AD8138ARZ −40°C to +85°C 1 AD8138ARZ-RL −40°C to +85°C 1 AD8138ARZ-R7 −40°C to +85°C AD8138ARM −40°C to +85°C AD8138ARM-REEL −40°C to +85°C AD8138ARM-REEL7 −40°C to +85°C 1 AD8138ARMZ −40°C to +85°C ...

  • Page 24

    AD8138 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C01073-0-1/06(F) Rev Page ...