LMH6715EP Enhanced Plastic Dual Wideband Video Op Amp General Description Features The LMH6715EP combines National's VIP10TM high speed complementary bipolar process with National's current feedback topology to produce a very high speed dual op amp. The LMH6715EP provides 400MHz small signal bandwidth at a gain of +2V/V and 1300V/s slew rate while consuming only 5.8mA per amplifier from 5V supplies. n TA = 25C, RL = 100, typical values unless specified. n Very low diff. gain, phase: 0.02%, 0.02 n Wide bandwidth: 480MHz (AV = +1V/V); 400MHz (AV = +2V/V) n 0.1dB gain flatness to 100MHz n Low power: 5.8mA/channel n -70dB channel-to-channel crosstalk (10MHz) n Fast slew rate: 1300V/s n Unity gain stable n Improved replacement for CLC412 The LMH6715EP offers exceptional video performance with its 0.02% and 0.02 differential gain and phase errors for NTSC and PAL video signals while driving up to four back terminated 75 loads. The LMH6715EP also offers a flat gain response of 0.1dB to 100MHz and very low channel-tochannel crosstalk of -70dB at 10MHz. Additionally, each amplifier can deliver 70mA of output current. This level of performance makes the LMH6715EP an ideal dual op amp for high density, broadcast quality video systems. Applications n Selected Military Applications n Selected Avionics Applications The LMH6715EP's two very well matched amplifiers support a number of applications such as differential line drivers and receivers. In addition, the LMH6715EP is well suited for Sallen Key active filters in applications such as anti-aliasing filters for high speed A/D converters. Its small 8-pin SOIC package, low power requirement, low noise and distortion allow the LMH6715EP to serve portable RF applications such as IQ channels. ENHANCED PLASTIC * Extended Temperature Performance of -40C to +85C * * * * * Baseline Control - Single Fab & Assembly Site Process Change Notification (PCN) Qualification & Reliability Data Solder (PbSn) Lead Finish is standard Enhanced Diminishing Manufacturing Sources (DMS) Support Ordering Information PART NUMBER VID PART NUMBER NS PACKAGE NUMBER (Note 3) LMH6715MAEP V62/04623-01 M08A (Notes 1, 2) TBD TBD Note 1: For the following (Enhanced Plastic) version, check for availability: LMH6715MAXEP. Parts listed with an "X" are provided in Tape & Reel and parts without an "X" are in Rails. Note 2: FOR ADDITIONAL ORDERING AND PRODUCT INFORMATION, PLEASE VISIT THE ENHANCED PLASTIC WEB SITE AT: www.national.com/ mil Note 3: Refer to package details under Physical Dimensions (c) 2004 National Semiconductor Corporation DS200885 www.national.com LMH6715EP Enhanced Plastic Dual Wideband Video Op Amp May 2004 LMH6715EP Enhanced Plastic Differential Gain & Phase with Multiple Video Loads Frequency Response vs. VOUT 20088516 20088508 www.national.com 2 Storage Temperature Range If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Lead Temperature (Soldering 10 sec) ESD Tolerance (Note 7) -65C to +150C +300C Operating Ratings Human Body Model 2000V Machine Model Thermal Resistance 150V VCC 6.75V IOUT (Note 6) Package SOIC Differential Input Voltage 145C/W -40C to +85C 5V to 6V Nominal Operating Voltage 2.2V Maximum Junction Temperature (JA) 65C/W Operating Temperature Range VCC Common-Mode Input Voltage (JC) +150C Electrical Characteristics AV = +2, RF = 500, VCC = 5 V, RL = 100; unless otherwise specified. Boldface limits apply at the temperature extremes. Symbol Parameter Conditions Min Typ Max Units Frequency Domain Response SSBW -3dB Bandwidth VOUT < 0.5VPP, RF = 300 LSBW -3dB Bandwidth VOUT < 4.0VPP, RF = 300 Gain Flatness VOUT < 0.5VPP GFP GFR Peaking Rolloff 280 DC to 100MHz, RF = 300 400 MHz 170 MHz 0.1 dB DC to 100MHz, RF = 300 0.1 dB LPD Linear Phase Deviation DC to 100MHz, RF = 300 0.25 deg DG Differential Gain RL = 150, 4.43MHz 0.02 % DP Differential Phase RL = 150, 4.43MHz 0.02 deg 1.4 ns Time Domain Response Tr Rise and Fall Time 0.5V Step 4V Step 3 ns Ts Settling Time to 0.05% 2V Step 12 ns OS Overshoot 0.5V Step 1 % SR Slew Rate 2V Step 1300 V/s Distortion And Noise Response HD2 2nd Harmonic Distortion 2VPP, 20MHz -60 dBc HD3 3rd Harmonic Distortion 2VPP, 20MHz -75 dBc Equivalent Input Noise VN Non-Inverting Voltage IN Inverting Current INN Non-Inverting Current SNF XTLKA Noise Floor Crosstalk > 1MHz > 1MHz > 1MHz > 1MHz -153 dB1Hz Input Referred 10MHz -70 dB 3.4 nV/ 10.0 pA/ 1.4 pA/ Static, DC Performance VIO DVIO IBN DIBN IBI DIBI PSRR 2 Input Offset Voltage Non-Inverting 30 5 Inverting 30 6 Average Drift Input Bias Current Average Drift Input Bias Current Average Drift Power Supply Rejection Ratio DC 46 44 3 6 8 mV V/C 12 20 A nA/C 21 35 A 20 nA/C 60 dB www.national.com LMH6715EP Enhanced Plastic Absolute Maximum Ratings (Note 4) LMH6715EP Enhanced Plastic Electrical Characteristics (Continued) AV = +2, RF = 500, VCC = 5 V, RL = 100; unless otherwise specified. Boldface limits apply at the temperature extremes. Min Typ CMRR Symbol Common Mode Rejection Ratio Parameter DC Conditions 50 47 56 ICC Supply Current per Amplifier RL = 4.7 4.1 5.8 Max Units dB 7.6 8.1 mA Miscellaneous Performance RIN Input Resistance Non-Inverting 1000 k CIN Input Capacitance Non-Inverting 1.0 pF ROUT Output Resistance Output Voltage Range Closed Loop RL = .06 VO 4.0 3.9 V VOL 3.5 3.4 RL = 100 CMIR Input Voltage Range IO Output Current Common Mode V 2.2 V 70 mA Note 4: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications, see the Electrical Characteristics tables. Note 5: Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self heating where TJ > TA. See Applications Section for information on temperature de-rating of this device." Min/Max ratings are based on product characterization and simulation. Individual parameters are tested as noted. Note 6: The maximum output current (IOUT) is determined by device power dissipation limitations. See the Power Dissipation section of the Application Division for more details. Note 7: Human body model, 1.5k in series with 100pF. Machine model, 0 In series with 200pF. Connection Diagram 8-Pin SOIC 20088504 Top View www.national.com 4 (TA = 25C, VCC = 5V, AV = 2V/V, RF = 500, RL = 100, Non-Inverting Frequency Response Inverting Frequency Response 20088513 20088512 Non-Inverting Frequency Response vs. VOUT Small Signal Channel Matching 20088516 20088501 Frequency Response vs. Load Resistance Non-Inverting Frequency Response vs. RF 20088515 20088514 5 www.national.com LMH6715EP Enhanced Plastic Typical Performance Characteristics unless otherwise specified). LMH6715EP Enhanced Plastic Typical Performance Characteristics (TA = 25C, VCC = 5V, AV = 2V/V, RF = 500, RL = 100, unless otherwise specified). (Continued) Small Signal Pulse Response Large Signal Pulse Response 20088518 20088519 Input-Referred Crosstalk Settling Time vs. Accuracy 20088507 20088524 -3dB Bandwidth vs. VOUT DC Errors vs. Temperature 20088526 20088525 www.national.com 6 Open Loop Transimpedance, Z(s) Equivalent Input Noise vs. Frequency 20088520 20088523 Differential Gain & Phase vs. Load Differential Gain vs. Frequency 20088509 20088508 Differential Phase vs. Frequency Gain Flatness & Linear Phase Deviation 20088510 20088511 7 www.national.com LMH6715EP Enhanced Plastic Typical Performance Characteristics (TA = 25C, VCC = 5V, AV = 2V/V, RF = 500, RL = 100, unless otherwise specified). (Continued) LMH6715EP Enhanced Plastic Typical Performance Characteristics (TA = 25C, VCC = 5V, AV = 2V/V, RF = 500, RL = 100, unless otherwise specified). (Continued) 2nd Harmonic Distortion vs. Output Voltage 3rd Harmonic Distortion vs. Output Voltage 20088502 20088505 Closed Loop Output Resistance PSRR & CMRR 20088506 20088517 Suggested RS vs. CL 20088527 www.national.com 8 Frequency Response vs. RF 20088535 FIGURE 1. Non-Inverting Configuration with Power Supply Bypassing 20088514 The plot labeled "Frequency Response vs. RF" shows the LMH6715EP's frequency response as RF is varied (RL = 100, AV = +2). This plot shows that an RF of 200 results in peaking and marginal stability. An RF of 300 gives near maximal bandwidth and gain flatness with good stability, but with very light loads (RL > 300) the device may show some peaking. An RF of 500 gives excellent stability with good bandwidth and is the recommended value for most applications. Since all applications are slightly different it is worth some experimentation to find the optimal RF for a given circuit. For more information see Application Note OA-13 which describes the relationship between RF and closedloop frequency response for current feedback operational amplifiers. When configuring the LMH6715EP for gains other than +2V/V, it is usually necessary to adjust the value of the feedback resistor. The two plots labeled "RF vs. Noninverting Gain" and "RF vs. Inverting Gain" provide recommended feedback resistor values for a number of gain selections. 20088537 FIGURE 2. Inverting Configuration with Power Supply Bypassing Application Introduction Offered in an 8-pin package for reduced space and cost, the wideband LMH6715EP dual current-feedback op amp provides closely matched DC and AC electrical performance characteristics making the part an ideal choice for wideband signal processing. Applications such as broadcast quality video systems, IQ amplifiers, filter blocks, high speed peak detectors, integrators and transimedance amplifiers will all find superior performance in the LMH6715EP dual op amp. 9 www.national.com LMH6715EP Enhanced Plastic FEEDBACK RESISTOR SELECTION One of the key benefits of a current feedback operational amplifier is the ability to maintain optimum frequency response independent of gain by using appropriate values for the feedback resistor (RF). The Electrical Characteristics and Typical Performance plots specify an RF of 500, a gain of +2V/V and 5V power supplies (unless otherwise specified). Generally, lowering RF from it's recommended value will peak the frequency response and extend the bandwidth while increasing the value of RF will cause the frequency response to roll off faster. Reducing the value of RF too far below it's recommended value will cause overshoot, ringing and, eventually, oscillation. Application Section LMH6715EP Enhanced Plastic Application Introduction pins are particularly sensitive to the coupling of parasitic capacitances (to AC ground) arising from traces or pads placed too closely ( < 0.1") to power or ground planes. In some cases, due to the frequency response peaking caused by these parasitics, a small adjustment of the feedback resistor value will serve to compensate the frequency response. Also, it is very important to keep the parasitic capacitance across the feedback resistor to an absolute minimum. (Continued) RF vs. Non-Inverting Gain The performance plots in the data sheet can be reproduced using the evaluation boards available from National. The CLC730036 board uses all SMT parts for the evaluation of the LMH6715EP. The board can serve as an example layout for the final production printed circuit board. Care must also be taken with the LMH6715EP's layout in order to achieve the best circuit performance, particularly channel-to-channel isolation. The decoupling capacitors (both tantalum and ceramic) must be chosen with good high frequency characteristics to decouple the power supplies and the physical placement of the LMH6715EP's external components is critical. Grouping each amplifier's external components with their own ground connection and separating them from the external components of the opposing channel with the maximum possible distance is recommended. The input (RIN) and gain setting resistors (RF) are the most critical. It is also recommended that the ceramic decoupling capacitor (0.1F chip or radial-leaded with low ESR) should be placed as closely to the power pins as possible. 20088521 Both plots show the value of RF approaching a minimum value (dashed line) at high gains. Reducing the feedback resistor below this value will result in instability and possibly oscillation. The recommended value of RF is depicted by the solid line, which begins to increase at higher gains. The reason that a higher RF is required at higher gains is the need to keep RG from decreasing too far below the output impedance of the input buffer. For the LMH6715EP the output resistance of the input buffer is approximately 160 and 50 is a practical lower limit for RG. Due to the limitations on RG the LMH6715EP begins to operate in a gain bandwidth limited fashion for gains of 5V/V or greater. POWER DISSIPATION Follow these steps to determine the Maximum power dissipation for the LMH6715EP: 1. Calculate the quiescent (no-load) power: PAMP = ICC (VCC - VEE) 2. Calculate the RMS power at the output stage: PO = (VCC -VLOAD)(ILOAD), where VLOAD and ILOAD are the voltage and current across the external load. 3. Calculate the total RMS power: Pt = PAMP + PO The maximum power that the LMH6715EP, package can dissipate at a given temperature can be derived with the following equation: Pmax = (150o - Tamb)/ JA, where Tamb = Ambient temperature (C) and JA = Thermal resistance, from junction to ambient, for a given package (C/W). For the SOIC package JA is 145C/W. RF vs. Inverting Gain MATCHING PERFORMANCE With proper board layout, the AC performance match between the two LMH6715EP's amplifiers can be tightly controlled as shown in Typical Performance plot labeled "SmallSignal Channel Matching". The measurements were performed with SMT components using a feedback resistor of 300 at a gain of +2V/V. The LMH6715EP's amplifiers, built on the same die, provide the advantage of having tightly matched DC characteristics. 20088522 When using the LMH6715EP as a replacement for the CLC412, identical bandwidth can be obtained by using an appropriate value of RF . The chart "Frequency Response vs. RF" shows that an RF of approximately 700 will provide bandwidth very close to that of the CLC412. At other gains a similar increase in RF can be used to match the new and old parts. SLEW RATE AND SETTLING TIME One of the advantages of current-feedback topology is an inherently high slew rate which produces a wider full power bandwidth. The LMH6715EP has a typical slew rate of 1300V/s. The required slew rate for a design can be calculated by the following equation: SR = 2fVpk. CIRCUIT LAYOUT With all high frequency devices, board layouts with stray capacitances have a strong influence over AC performance. The LMH6715EP is no exception and its input and output www.national.com 10 Applications Circuits (Continued) Careful attention to parasitic capacitances is critical to achieving the best settling time performance. The LMH6715EP has a typical short term settling time to 0.05% of 12ns for a 2V step. Also, the amplifier is virtually free of any long term thermal tail effects at low gains. SINGLE-TO-DIFFERENTIAL LINE DRIVER The LMH6715EP's well matched AC channel-response allows a single-ended input to be transformed to highly matched push-pull driver. From a 1V single-ended input the circuit of Figure 3 produces 1V differential signal between the two outputs. For larger signals the input voltage divider (R1 = 2R2) is necessary to limit the input voltage on channel 2. When measuring settling time, a solid ground plane should be used in order to reduce ground inductance which can cause common-ground-impedance coupling. Power supply and ground trace parasitic capacitances and the load capacitance will also affect settling time. Placing a series resistor (Rs) at the output pin is recommended for optimal settling time performance when driving a capacitive load. The Typical Performance plot labeled "RS and Settling Time vs. Capacitive Load" provides a means for selecting a value of Rs for a given capacitive load. DC & NOISE PERFORMANCE A current-feedback amplifier's input stage does not have equal nor correlated bias currents, therefore they cannot be canceled and each contributes to the total DC offset voltage at the output by the following equation: The input resistance is the resistance looking from the noninverting input back toward the source. For inverting DCoffset calculations, the source resistance seen by the input resistor Rg must be included in the output offset calculation as a part of the non-inverting gain equation. Application note OA-7 gives several circuits for DC offset correction. The noise currents for the inverting and non-inverting inputs are graphed in the Typical Performance plot labeled "Equivalent Input Noise". A more complete discussion of amplifier inputreferred noise and external resistor noise contribution can be found in OA-12. 20088545 FIGURE 3. Single-to-Differential Line Driver DIFFERENTIAL LINE RECEIVER Figure 4 and Figure 5 show two different implementations of an instrumentation amplifier which convert differential signals to single-ended. Figure 5 allows CMRR adjustment through R2. DIFFERENTIAL GAIN & PHASE The LMH6715EP can drive multiple video loads with very low differential gain and phase errors. The Typical Performance plots labeled "Differential Gain vs. Frequency" and "Differential Phase vs. Frequency" show performance for loads from 1 to 4. The Electrical Characteristics table also specifies performance for one 150 load at 4.43MHz. For NTSC video, the performance specifications also apply. Application note OA-24 "Measuring and Improving Differential Gain & Differential Phase for Video", describes in detail the techniques used to measure differential gain and phase. I/O VOLTAGE & OUTPUT CURRENT The usable common-mode input voltage range (CMIR) of the LMH6715EP specified in the Electrical Characteristics table of the data sheet shows a range of 2.2 volts. Exceeding this range will cause the input stage to saturate and clip the output signal. The output voltage range is determined by the load resistor and the choice of power supplies. With 5 volts the class A/B output driver will typically drive 3.9V into a load resistance of 100. Increasing the supply voltages will change the common-mode input and output voltage swings while at the same time increase the internal junction temperature. 20088546 FIGURE 4. Differential Line Receiver 11 www.national.com LMH6715EP Enhanced Plastic Application Introduction LMH6715EP Enhanced Plastic Applications Circuits (Continued) LOW NOISE WIDE-BANDWIDTH TRANSIMPEDANCE AMPLIFIER Figure 7 implements a low noise transimpedance amplifier using both channels of the LMH6715EP. This circuit takes advantage of the lower input bias current noise of the noninverting input and achieves negative feedback through the second LMH6715EP channel. The output voltage is set by the value of RF while frequency compensation is achieved through the adjustment of RT. 20088547 FIGURE 5. Differential Line Receiver with CMRR Adjustment NON-INVERTING CURRENT-FEEDBACK INTEGRATOR The circuit of Figure 6 achieves its high speed integration by placing one of the LMH6715EP's amplifiers in the feedback loop of the second amplifier configured as shown. 20088550 FIGURE 7. Low-Noise, Wide Bandwidth, Transimpedance Amp. 20088549 FIGURE 6. Current Feedback Integrator www.national.com 12 LMH6715EP Enhanced Plastic Dual Wideband Video Op Amp Physical Dimensions inches (millimeters) unless otherwise noted 8-Pin SOIC NS Package Number M08A LIFE SUPPORT POLICY NATIONAL'S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems 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. 2. A critical component is any component of 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. BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ``Banned Substances'' as defined in CSP-9-111S2. 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