December 4, 2008
LMH730227/LMH730216/LMH730165
Single High Speed Op Amp Evaluation Boards (SOIC,
SOT-23, and SC-70)
The LMH730227, LMH730216 and LMH730165 evaluation
boards are designed to aid in the characterization of National
Semiconductor's High Speed monolithic amplifiers.
LMH730227 — SOIC packages
LMH730216 — SOT-23 packages
LMH730165 — SC-70 packges
Use the evaluation boards as a guide for high frequency lay-
out and as a tool to aid in device testing and characterization.
The evaluation boards accommodate general purpose am-
plifiers, as well as amplifiers with the following features:
Supply current adjustment via external Resistor
Output disable
The evaluation board schematic is shown below. Refer to the
product data sheets for recommendations for component val-
ues.
BASIC OPERATION
These boards have identical circuit configurations and are
designed to accommodate both non-inverting and inverting
operation. By changing RT or RIN and ROUT different input
and output impedances can be matched. The SMA connec-
tors and board traces are optimized for 50 operation, how-
ever other impedances can be matched as shown below.
Inverting Gain = RF/RG (Input Resistance = RT || RG)
Non Inverting Gain = 1 + RF/(RG + RT)
(Input Resistance = RIN)
(RT may be set to zero for non inverting operation)
For current feedback operational amplifiers be careful to use
appropriate values of RF. In addition the required value of
RG will limit choices for input impedance with Inverting gains.
20066601
FIGURE 1. SOT-23 and SC-70 Schematic
© 2008 National Semiconductor Corporation 200666 www.national.com
LMH730227/LMH730216/ LMH730165 Single High Speed Op Amp Evaluation Boards (SOIC,
SOT-23 and SC-70)
LAYOUT CONSIDERATIONS
Printed circuit board layout and supply bypassing play major
roles in determining high frequency performance. When de-
signing your own board use these evaluation boards as a
guide and follow these steps to optimize high frequency per-
formance:
20066602
FIGURE 2. SOIC Schematic
20066603
FIGURE 3. Probe Schematic
www.national.com 2
LMH730227,LMH730216
1. Use a ground plane
2. Include large (~6.8μF) capacitors on both supplies.
3. Near the device use .01μF ceramic capacitors from both
supplies to ground C1, C3.
4. Near the device use a .1μF ceramic capacitor between
the supplies C5.
5. Remove the ground and power planes from under and
around the part, especially the input and output pins.
6. Minimize all trace lengths.
7. Use terminated transmission lines for long traces.
8. High-speed disable/enable operation requires that the
enable pin be treated as a signal input.
Diode D1 is to protect the device from reverse polarity supply
connections and will not be necessary for most designs.
Capacitor C5 is necessary for best Harmonic Distortion per-
formance. If C5 is not used increase the values of C1 and C3
to .1μF.
RIN, RT and ROUT are all impedance matching resistors. RIN
and ROUT should be equal to the desired input/output
impedance. RT || RG should equal the desired inverting input
impedance. Note that with current feedback op amps, the op-
timum value of RF and RG is determined by the desired gain
and raising RG to obtain higher input impedance may require
compromising device performance at large values of inverting
gain.
The disable trace has provisions for input termination. There
are also pads for series resistance and capacitance for pro-
grammable gain parts. See part datasheets for suggested
values.
Sample artwork for National's Evaluation boards is included
below.
The board is designed for 50 input and output connections
into coaxial cables. For other impedances the terminating re-
sistors can be modified to help match different impedances.
Do not use normal oscilloscope probes to test these circuits.
The capacitive loading will change circuit performance dras-
tically. Instead use low impedance resistive divider probes of
100 to 500. See Figure 3 for a sample resistive probe. The
Low impedance resistor should be 50-450. The ground con-
nection should be as short as possible (~1/2"). Even with
careful use of these probes results should be considered pre-
liminary until verified with controlled impedance measure-
ments. Even the best probes will interfere with circuit
operation to some degree. Also, conductors, fingers etc. near
the device will change measurement results.
National Semiconductor Layer1 Silk
20066604
National Semiconductor Layer2 Silk
20066605
SOIC Board Layout (Actual size = 1.5" x 1.5"). The boards may be marked as CLC730227 or LMH730227
3 www.national.com
LMH730227,LMH730216
National Semiconductor Layer2 Silk
20066610
National Semiconductor Layer1 Silk
20066611
SOT-23 Board Layout (Actual size = 1.5" x 1.5").
National Semiconductor Layer1 Silk
20066608
National Semiconductor Layer2 Silk
20066609
SC-70 Board Layout (Actual size = 1.5" x 1.5")
www.national.com 4
LMH730227,LMH730216
5 www.national.com
LMH730227,LMH730216
Notes
LMH730227/LMH730216/ LMH730165 Single High Speed Op Amp Evaluation Boards (SOIC,
SOT-23 and SC-70)
For more National Semiconductor product information and proven design tools, visit the following Web sites at:
Products Design Support
Amplifiers www.national.com/amplifiers WEBENCH® Tools www.national.com/webench
Audio www.national.com/audio App Notes www.national.com/appnotes
Clock and Timing www.national.com/timing Reference Designs www.national.com/refdesigns
Data Converters www.national.com/adc Samples www.national.com/samples
Interface www.national.com/interface Eval Boards www.national.com/evalboards
LVDS www.national.com/lvds Packaging www.national.com/packaging
Power Management www.national.com/power Green Compliance www.national.com/quality/green
Switching Regulators www.national.com/switchers Distributors www.national.com/contacts
LDOs www.national.com/ldo Quality and Reliability www.national.com/quality
LED Lighting www.national.com/led Feedback/Support www.national.com/feedback
Voltage Reference www.national.com/vref Design Made Easy www.national.com/easy
PowerWise® Solutions www.national.com/powerwise Solutions www.national.com/solutions
Serial Digital Interface (SDI) www.national.com/sdi Mil/Aero www.national.com/milaero
Temperature Sensors www.national.com/tempsensors Solar Magic® www.national.com/solarmagic
Wireless (PLL/VCO) www.national.com/wireless Analog University® www.national.com/AU
THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION
(“NATIONAL”) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY
OR COMPLETENESS OF THE CONTENTS OF THIS PUBLICATION AND RESERVES THE RIGHT TO MAKE CHANGES TO
SPECIFICATIONS AND PRODUCT DESCRIPTIONS AT ANY TIME WITHOUT NOTICE. NO LICENSE, WHETHER EXPRESS,
IMPLIED, ARISING BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THIS
DOCUMENT.
TESTING AND OTHER QUALITY CONTROLS ARE USED TO THE EXTENT NATIONAL DEEMS NECESSARY TO SUPPORT
NATIONAL’S PRODUCT WARRANTY. EXCEPT WHERE MANDATED BY GOVERNMENT REQUIREMENTS, TESTING OF ALL
PARAMETERS OF EACH PRODUCT IS NOT NECESSARILY PERFORMED. NATIONAL ASSUMES NO LIABILITY FOR
APPLICATIONS ASSISTANCE OR BUYER PRODUCT DESIGN. BUYERS ARE RESPONSIBLE FOR THEIR PRODUCTS AND
APPLICATIONS USING NATIONAL COMPONENTS. PRIOR TO USING OR DISTRIBUTING ANY PRODUCTS THAT INCLUDE
NATIONAL COMPONENTS, BUYERS SHOULD PROVIDE ADEQUATE DESIGN, TESTING AND OPERATING SAFEGUARDS.
EXCEPT AS PROVIDED IN NATIONAL’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, NATIONAL ASSUMES NO
LIABILITY WHATSOEVER, AND NATIONAL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY RELATING TO THE SALE
AND/OR USE OF NATIONAL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR
PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY
RIGHT.
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR
SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
Life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and
whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected
to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform
can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness.
National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other
brand or product names may be trademarks or registered trademarks of their respective holders.
Copyright© 2008 National Semiconductor Corporation
For the most current product information visit us at www.national.com
National Semiconductor
Americas Technical
Support Center
Email: support@nsc.com
Tel: 1-800-272-9959
National Semiconductor Europe
Technical Support Center
Email: europe.support@nsc.com
German Tel: +49 (0) 180 5010 771
English Tel: +44 (0) 870 850 4288
National Semiconductor Asia
Pacific Technical Support Center
Email: ap.support@nsc.com
National Semiconductor Japan
Technical Support Center
Email: jpn.feedback@nsc.com
www.national.com
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements,
and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should
obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are
sold subject to TIs terms and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TIs standard
warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where
mandated by government requirements, testing of all parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and
applications using TI components. To minimize the risks associated with customer products and applications, customers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right,
or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information
published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a
warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual
property of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied
by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive
business practice. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional
restrictions.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all
express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not
responsible or liable for any such statements.
TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would reasonably
be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement specifically governing
such use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications of their applications, and
acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products
and any use of TI products in such safety-critical applications, notwithstanding any applications-related information or support that may be
provided by TI. Further, Buyers must fully indemnify TI and its representatives against any damages arising out of the use of TI products in
such safety-critical applications.
TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are
specifically designated by TI as military-grade or "enhanced plastic."Only products designated by TI as military-grade meet military
specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is solely at
the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in connection with such use.
TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products are
designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designated
products in automotive applications, TI will not be responsible for any failure to meet such requirements.
Following are URLs where you can obtain information on other Texas Instruments products and application solutions:
Products Applications
Audio www.ti.com/audio Automotive and Transportation www.ti.com/automotive
Amplifiers amplifier.ti.com Communications and Telecom www.ti.com/communications
Data Converters dataconverter.ti.com Computers and Peripherals www.ti.com/computers
DLP®Products www.dlp.com Consumer Electronics www.ti.com/consumer-apps
DSP dsp.ti.com Energy and Lighting www.ti.com/energy
Clocks and Timers www.ti.com/clocks Industrial www.ti.com/industrial
Interface interface.ti.com Medical www.ti.com/medical
Logic logic.ti.com Security www.ti.com/security
Power Mgmt power.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense
Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video
RFID www.ti-rfid.com
OMAP Mobile Processors www.ti.com/omap
Wireless Connectivity www.ti.com/wirelessconnectivity
TI E2E Community Home Page e2e.ti.com
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright ©2012, Texas Instruments Incorporated
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Texas Instruments:
LMH730165/NOPB LMH730216/NOPB LMH730227/NOPB