Texas Instruments THS3001 User's Manual
Contents
1. 100K 1M 10M 100M 1G f Frequency Hz General Information 1 7 General High Speed Amplifier Design Considerations 1 6 General High Speed Amplifier Design Considerations The THS3001 EVM layout has been designed and optimized for use with high speed signals and can be used as an example when designing THS3001 applications Careful attention has been given to component selection grounding power supply bypassing and signal path layout Disregard of these basic design considerations could result in less than optimum performance of the THS3001 high speed current feedback video operational amplifier Surface mount components were selected because of the extremely low lead inductance associated with this technology Also because surface mount components are physically small the layout can be very compact This helps minimize both stray inductance and capacitance Tantalum power supply bypass capacitors C1 and C3 for original and C1 and C2 for Rev A at the power input pads help supply currents for rapid large signal changes at the amplifier output The 0 1 uF power supply bypass capacitors C2 and C4 for original version and C3 and C4 for Rev A were placed as close as possible to the IC power input pins in order to keep the PCB trace inductance to a minimum This improves high frequency bypassing and reduces harmonic distortion A proper ground plane on both sides of the PCB shoul2. NONINVERTING C3 Figure 1 3 THS3001 SLOP130 RevA THS3001 EVM Board The THS3001 EVM is equipped with both noninverting and inverting inputs The noninverting input is set for a gain of 2 and the inverting input is set for a gain of 1 Each input is terminated with a 50 O resistor to provide correct line impedance matching Figure 1 3 for original version and Figure 1 4 for Rev A The amplifier IC output is routed through a 50 Q resistor both to provide correct line impedance matching and to help isolate capacitive loading on the output of the amplifier Capacitive loading directly on the output of the IC decreases the amplifier s phase margin and can result in peaking or oscillations EVM Schematic Original Version C2 Vcc 0 1 uF C1 mE R1 6 8 uF 35 V Non JI Invertin pee d R2 J2 gt Output 49 9 A J3 B Inverting Input L C3 R4 L C4 6 8 uF 35 V 49 9 Q 0 1 uF Vcc General Information 1 3 Description Figure 1 4 THS3001 Rev A EVM Schematic J1 Vcc C2 4 6 8 uF Vcc gt Vcc Hf 2 GND C3 3 0 1 uF Yee y Vee R2 R4 0 IN a 1kQ 1kQ Inverting R1 4990 J4 Rev A i Out IN Noninverting R3 49 9 Q Vcc Even though the THS3001 is a current feedback amplifier the gain of the EVM can easil
3. D 1206 1206 1206 SOIC 8 Manufacturer Digi Key Part Number Sprague 293D685X9035D2T Sprague 11C1201E104M5NT Amphenol ARF1205 ND Digi Key P49 9CTR ND Digi Key P1 0KCTR ND TI THS3001 Board layout examples of the THS3001 EVM PCB are shown in the following illustrations They are not to scale and appear here only as a reference Figure 2 1 THS3001 EVM Component Placement Silkscreen and Solder Pads IN GND INVERTING NONINVERTING TUS ee m IN 7 153 LIE ll o LITERATURE NO e Ji SLOP 130 THS3001 EVM 2 2 3 009957 amp Reference THS3001 EVM Board Layouts Figure 2 2 THS3001 EVM PC Board Layout Component Side Mao o MN Liv Y Y wT YY Reference 2 3 THS3001 Rev A High Speed Operational Amplifier EVM Parts List 2 3 THS3001 Rev A High Speed Operational Amplifier EVM Parts List Table 2 2 THS3001 Rev A EVM Parts List Manufacturer Digi Key C1 C2 Capacitor 6 8 uF 35 V SM D Sprague 293D685X9035D2T C3 C4 Capacitor 0 1 uF ceramic 10 SM 1206 Sprague 11C1201E104M5NT J1 Terminal Block Digi Key ED1515 ND J2 J3 J4 Connector SMA 50 0 vertical PC Amphenol ARF1205 ND mount through hole R1 R3 R5 Resistor 49 9 Q 1 1 8 W SM 1206 Digi Key P49 9CTR ND R2 R4 Resistor 1 KQ 1 1 8 W SM 1206 Digi Key P1 0KCTR ND U1 IC THS3001 operational amplifier SOIC 8 TI THS3001 PCB1 PCB THS3001 Rev A EVM 2
4. 4 THS3001 Rev A EVM Board Layouts Board layout examples of the THS3001 Rev A EVM PCB are shown in the following illustrations They are not to scale and appear here only as a reference Figure 2 4 THS3001 Rev A EVM Component Placement Silkscreen and Solder Pads J1 e cooo 1 GN C2 J2 C D O END O O TEXAS INVERTING INSTRUMENTS Rev A NONINVERTING R1 O IN g R3 GND O O J3 O SLOP130 RevA THS3001 EVM Board 2 4 Reference THS3001 Rev A EVM Board Layouts Figure 2 5 THS3001 Rev A EVM PC Board Layout Component Side Rev A 6 Yo To Www Rev A Reference 2 5 2 6 Reference
5. M features include m High Bandwidth 340 MHz 3 dB at 15 Vcc amp Gain 2 B 5 V to 15 V Operation B Inverting and Noninverting Single Ended Inputs m Module Gain Set to 2 Noninverting and 1 Inverting Adjustable Through Component Change Nominal 50 Q Impedance Inputs and Outputs B Standard SMA Miniature RF Connectors m Good Example of High Speed Amplifier Design and Layout The TI THS3001 high speed current feedback operational amplifier evaluation module EVM is a complete high speed amplifier circuit It consists of the Tl THS3001 high speed current feedback operational amplifier IC along with a small number of passive parts mounted on a small circuit board measuring approximately 1 7 inch by 1 4 inch The EVM uses standard SMA miniature RF connectors for inputs and outputs and is completely assembled fully tested and ready to use just connect it to power a signal source and a load if desired Two versions of the THS3001 EVM are available The original appears in Figure 1 1 and the Rev A version appears in Figure 1 2 Figure 1 1 THS3001 Evaluation Module Original Version LITERATURE NO SLOP 130 THS3001 EVM General Information Description Figure 1 2 THS3001 Rev A Evaluation Module Rev A O Y TEXAS INVERTING INSTRUMENTS R4 J4
6. NDERSTOOD TO BE FULLY AT THE CUSTOMER S RISK In order to minimize risks associated with the customer s applications adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards TI assumes no liability for applications assistance or customer product design TI does not warrant or represent that any license either express or implied is granted under any patent right copyright mask work right or other intellectual property right of TI covering or relating to any combination machine or process in which such semiconductor products or services might be or are used TI s publication of information regarding any third party s products or services does not constitute Tl s approval warranty or endorsement thereof Copyright 1999 Texas Instruments Incorporated Preface Related Documentation From Texas Instruments B THS3001 HIGH SPEED CURRENT FEEDBACK OPERATIONAL AMPLIFIER literature number SLOS217 This is the data sheet for the THS3001 operational amplifier integrated circuit that is used in the THS3001 evaluation module FCC Warning This equipment is intended for use in a laboratory test environment only It generates uses and can radiate radio frequency energy and has not been tested for compliance with the limits of computing devices pursuant to subpart J of part 15 of FCC rules which are designed to provide reasonable protection against radio frequency interference Op
7. Wi TEXAS INSTRUMENTS THS3001 High Speed Current Feedback Operational Amplifier Users Guide March 1999 Mixed Signal Products SLOU021A IMPORTANT NOTICE Texas Instruments and its subsidiaries Tl reserve the right to make changes to their products or to discontinue any product or service without notice and advise customers to obtain the latest version of relevant information to verify before placing orders that information being relied on is current and complete All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement including those pertaining to warranty patent infringement and limitation of liability TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with Tl s standard warranty Testing and other quality control techniques are utilized to the extent TI deems necessary to support this warranty Specific testing of all parameters of each device is not necessarily performed except those mandated by government requirements CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH PERSONAL INJURY OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE CRITICAL APPLICATIONS TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN LIFE SUPPORT DEVICES OR SYSTEMS OR OTHER CRITICAL APPLICATIONS INCLUSION OF TI PRODUCTS IN SUCH APPLICATIONS IS U
8. d VCC and VCC 3 Connect the power supply ground to the module pad marked GND 4 Connect an oscilloscope to the module SMA output connector J2 through a 50 Q nominal impedance cable an oscilloscope having a 50 Q input termination is preferred for examining very high frequency signals 5 Set the power supply to ON 6 Connect the signal input to either the noninverting input J1 for a gain of 2 or to the inverting input J3 for a gain of 1 1 4 2 Steps for THS3001 Rev A EVM 1 Ensure that all power supplies are set to OFF before making power supply connections to the THS3001 EVM 2 Select the operating voltage for the EVM and connect appropriate split power supplies to J7 terminals on the module marked VCC and VCC 3 Connect the power supply ground to J7 terminal marked GND 4 Connect an oscilloscope to the module SMA output connector J4 through a 50 O nominal impedance cable an oscilloscope having a 50 Q input termination is preferred for examining very high frequency signals 5 Setthe power supply to ON 6 Connect the signal input to either the noninverting input J3 for a gain of 2 orto the inverting input J2 for a gain of 1 Note that each input connector is terminated with a 50 O resistor to ground With a 50 O source impedance the voltage seen by the THS3001 amplifier IC on the module will be 12 the source signal voltage applied to the EVM 7 Verify the output signal on the oscilloscope No
9. d always be used with high speed circuit design This provides low inductive ground connections for return current paths In the area of the amplifier IC input pins however the ground plane was removed to minimize stray capacitance and reduce ground plane noise coupling into these pins This is especially important for the inverting pin while the amplifier is operating in the noninverting mode Because the voltage at this pin swings directly with the noninverting input voltage any stray capacitance would allow currents to flow into the ground plane causing possible gain error and or oscillation Capacitance variations at the amplifier IC inverting input pin of less than 1 pF can significantly affect the response of the amplifier In general it is always best to keep signal lines as short and as straight as possible Sharp 90 corners should be avoided round corners or a series of 45 bends should be used instead Stripline techniques should also be incorporated when signal lines are greater than three inches in length These traces should be designed with a characteristic impedance of either 50 Q or 75 Q as required by the application Such signal lines should also be properly terminated with an appropriate resistor Finally proper termination of all inputs and outputs should be incorporated into the layout Unterminated lines such as coaxial cable can appear to be a reactive load to the amplifier IC By terminating a transmission line
10. eration of this equipment in other environments may cause interference with radio communications in which case the user at his own expense will be required to take whatever measures may be required to correct this interference Trademarks Tl is a trademark of Texas Instruments Incorporated 1 Ld d gg oo Eon DOL RO NVNNNNN 2na oa ro Contents General Information us cee eae eee n GR a 1 1 Tall TRUCOS a sa 1 2 1 2 Description i 2e2a odavna ia oda ada deeb rE R e died aa 1 2 1 38 THS3001 EVM Specifications ssssssssssssse se 1 5 1 4 Using The THS3001 EVM 0000 e eee eee 1 6 1 5 THS3001 EVM Performance csisriiicisirieiiadin waki netdi e 1 7 1 6 General High Speed Amplifier Design Considerations oocooooccccccocoo 1 8 Reference PLI 2 1 2 1 THS3001 High Speed Operational Amplifier EVM Parts List 2 2 2 2 THS3001 EVM Board Layouts 0 0 eee ee eens 2 2 2 3 THS3001 Rev A High Speed Operational Amplifier EVM Parts List 2 4 2 4 THS3001 Rev A EVM Board Layouts 0c cece eects 2 4 Figures THS3001 Evaluation Module Original Version a 1 2 THS3001 Rev A Evaluation Module aa 1 3 THS3001 EVM Schematic Original Version cece eee eee 1 3 THS3001 Rev A EVM Schematic aaa 1 4 THS3001 EVM Frequency Response with Gain 2 a 1 7 THS3001 EVM Frequency Response with I
11. nverting Gain 2 1 000005 1 7 THS3001 EVM Component Placement Silkscreen and Solder Pads 2 2 THS3001 EVM PC Board Layout Component Side 0000 cece o 2 3 THS3001 EVM PC Board Layout Back Side aaa 2 3 THS3001 Rev AEVM Component Placement Silkscreen and Solder Pads 2 4 THS3001 Rev A EVM PC Board Layout Component Side Luuuuue 2 5 THS3001 Rev A EVM PC Board Layout Back Side 2 222222 2 0 c eee 2 5 THS300 EVM Parts EISE cs e ae 2 2 THS3001 Rev A EVM Parts List 0 cee III 2 4 vi Chapter 1 General Information This chapter details the Texas Instruments TI THS3001 high speed operational amplifier evaluation module EVM SLOP130 It includes a list of EVM features a brief description of the module illustrated with a pictorial and aschematic diagram EVM specifications details on connecting and using the EVM and a discussion on high speed amplifier design considerations Topic Page dab ARETES a sacas orcos oros aVor 1 2 de LESEN osocaconononcosanorondanenogonoco o oroa canon ndar 1 2 1 3 THS3001 EVM Specifications ccc eee eee eee eee nn 1 5 14 Usingslihe3rElS300 1 EVMIEC n ERES 1 6 1 5 THS3001 EVM Performance aaa aaa aaa aaa 1 7 1 6 General High Speed Amplifier Design Considerations 1 8 Features 1 1 Features 1 2 Description THS3001 operational amplifier EV
12. te The signal shown on an oscilloscope with a 50 O input impedance will be the actual THS3001 amplifier IC output voltage This is due to the voltage division between the output resistor R2 and the oscilloscope input impedance General Information THS3001 EVM Performance 1 5 THS3001 EVM Performance Figure 1 5 shows the typical frequency response of the THS3001 EVM using the noninverting input G 2 Typical values show a 3 dB bandwidth of 340 MHz with a 15 V power supply and 260 MHz with a 5 V power supply They also show a 0 1 dB frequency response of 17 MHz with a 15 V power supply and 20 MHz with a 5 V power supply Figure 1 5 THS3001 EVM Frequency Response with Gain 2 Output Amplitude dB 100K 1M 10M 100M 1G f Frequency Hz Figure 1 6 shows the typical frequency response of the THS3001 EVM using the inverting input G 1 Typical 0 1 dB bandwidths are 15 MHz with a 15 V power supply and 17 MHz with a 5 V power supply Typical 3 dB bandwidths are 220 MHz at 15 V and 210 MHz at 5 V Figure 1 6 THS3001 EVM Frequency Response with Inverting Gain 1 Output Amplitude dB 1 0 1 2 3 4 5 6 7 Voc i5 V Vi 200 mV RMS Rioad 150 2
13. w the input signal sources are configured The gain equations given above assume no signal loss in either the input or the output The EVM circuit board is an excellent example of proper board layout for high speed amplifier designs and can be used as a guide for user application board layouts 1 3 THS3001 EVM Specifications Supply voltage range EV CE rr 5 Vto 15 V Supply Curent ISE sse seder nn nn e nak oo h d S bt 6 5 mA Typ Input voltage Vi saso ga A AA i Ed Ske hd VCC Max Output drive Io m nn 100 mA Typ Continuous power dissipation at TA 25 C 1 aaa 740 mW For complete THS3001 amplifier IC specifications and parameter measurement information and additional application information see the THS3001 data sheet TI Literature Number SLOS217 General Information 1 5 Using The THS3001 EVM 1 4 Using The THS3001 EVM The THS3001 EVM operates from power supply voltages ranging from 5 V to 15 V As shipped the inverting input gain of the module is set to 1 the noninverting input gain is set to 2 and signal inputs on the module are terminated for 50 Q nominal impedance cables An oscilloscope is typically used to view and analyze the EVM output signal 1 4 1 Steps for THS3001 EVM 1 Ensure that all power supplies are set to OFF before making power supply connections to the THS3001 EVM 2 Select the operating voltage for the EVM and connect appropriate split power supplies to the pads on the module marke
14. with its characteristic impedance the amplifier s load then appears to be purely resistive and reflections are absorbed at each end of the line Another advantage of using an output termination resistor is that capacitive loads are isolated from the amplifier output This isolation helps minimize the reduction in amplifier phase margin and improves the amplifier stability for improved performance such as reduced peaking and settling times General Information Chapter 2 Reference This chapter includes a parts listand PCB layout illustrations for the THS3001 EVM and the THS3001 Rev A EVM Topic Page 2 1 THS3001 High Speed Operational Amplifier EVM Parts List 2 2 2 2 THS3001 EVM Board Layouts 0 ccc eee aaa 2 2 2 3 THS3001 Rev A High Speed Operational Amplifier EVM Parts List 2 4 2 4 THS3001 Rev A EVM Board Layouts 000eeeeeeeeeeee 2 4 2 1 THS3001 High Speed Current Feedback Video Operational Amplifier EVM Parts List 2 1 THS3001 High Speed Current Feedback Video Operational Amplifier EVM Parts List Table 2 1 THS3001 EVM Parts List Reference Description C1 C3 Capacitor 6 8 uF 35 V SM C2 C4 Capacitor 0 1 uF ceramic 10 SM J1 J2 J3 Connector SMA 50 0 vertical PC mount through hole R2 R3 R4 Resistor 49 9 Q 1 1 10 W SM R1 R5 Resistor 1 kO 1 1 10 W SM U1 IC THS3001 operational amplifier PCB1 PCB THS3001 EVM 2 2 THS3001 EVM Board Layouts Size
15. y be changed to support a particular application by simply changing the ratio of resistors R1 R4 and R5 R1 R2 and R4 for Rev A as described in the following equations Rr_ R1_ R4 Inverting Gain Re RS ORE Rev A f TEE Rp _ RI _ R4 Noninverting Gain 1 Re 1 RAER 1 R2 4 RI Rev A In addition some applications such as those for video may require the use of 75 Q cable and 75 Q EVM input termination and output isolation resistors Any of the resistors on the EVM board can be replaced with a resistor of a different value however care must be taken because the surface mount solder pads on the board are somewhat fragile and will not survive many desoldering soldering operations Because of the current feedback architecture extra care must be taken to ensure that a feedback resistor is always included in the design In addition there must never be a capacitor directly in the feedback path between the amplifier output and the noninverting input Disregarding this guideline will likely result in a part that oscillates 1 4 General Information THS3001 EVM Specifications Note External factors can significantly affect the overall gain of the EVM For example connecting test equipment with 50 Q input impedance to the EVM output will divide the output signal level by a factor of 2 assuming the output isolation resistor on the EVM board remains 50 Q Similar effects can occur at the input depending upon ho
Download Pdf Manuals
Related Search