MICROCIRCUIT DATA SHEET Original Creation Date: 03/16/00 Last Update Date: 08/31/00 Last Major Revision Date: 03/16/00 MNLM7171AM-X-RH REV 0B0 VERY HIGH SPEED, HIGH OUTPUT CURRENT, VOLTAGE FEEDBACK AMPLIFIER: ALSO AVAILABLE GUARANTEED TO 300K RAD(Si) TESTED TO MIL-STD-883, METHOD 1019.5 General Description The LM7171 is a high speed voltage feedback amplifier that has the slewing characteristic of a current feedback amplifier; yet it can be used in all traditional voltage feedback amplifier configurations. The LM7171 is stable for gains as low as + 2 or -1. It provides a very high slew rate at 2000V/uS (Minimum) and a wide gain-bandwidth product of 170MHz (Minimum) while consuming only 6.5mA of supply current. It is ideal for video and high speed signal processing applications such as HDSL and pulse amplifiers. With 100mA output current, the LM7171 can be used for video distribution, as a transformer driver, or as a laser diode driver. Operation on +15V power supplies allows for large signal swings and provides greater dynamic range and signal-to-noise ratio. The LM7171 is ideal for ADC/DAC systems. In addition, the LM7171 is specified for +5V operation for portable applications. The LM7171 is built on National's advanced VIP(TM)III(Vertically integrated PNP) complementary bipolar process. Industry Part Number NS Part Numbers LM7171AM LM7171AMJ-QML LM7171AMJ-QMLV LM7171AMJFQML LM7171AMJFQMLV LM7171AMW-QML LM7171AMW-QMLV LM7171AMWG-QML LM7171AMWG-QMLV LM7171AMWGFQML LM7171AMWGFQMLV Prime Die LM7171 Controlling Document See Features Section Processing Subgrp Description 1 2 3 4 5 6 7 8A 8B 9 10 11 MIL-STD-883, Method 5004 Quality Conformance Inspection MIL-STD-883, Method 5005 1 Static tests at Static tests at Static tests at Dynamic tests at Dynamic tests at Dynamic tests at Functional tests at Functional tests at Functional tests at Switching tests at Switching tests at Switching tests at Temp ( oC) +25 +125 -55 +25 +125 -55 +25 +125 -55 +25 +125 -55 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 Features (Typical) - Easy to use Voltage Feedback Topology - Very High Slew Rate - Wide Unity-Gain Bandwidth - -3dB Frequency @ Av = +2 - Low Supply Current - High Open Loop Gain - High Output Current - Specified for +15V and +5V operation CONTROLLING DOCUMENTS: LM7171AMJ-QML 5962-9553601QPA LM7171AMJ-QMLV 5962-9553601VPA LM7171AMJFQML 5962F9553601QPA LM7171AMJFQMLV 5962F9553601VPA LM7171AMW-QML 5962-9553601QHA LM7171AMW-QMLV 5962-9553601VHA LM7171AMWG-QML 5962-9553601QXA LM7171AMWG-QMLV 5962-9553601VXA LM7171AMWGFQML 5962F9553601QXA LM7171AMWGFQMLV 5962F9553601VXA 2400V/us 200Mhz 220 Mhz 6.5 mA 85 dB 100 mA Applications - HDSL and ADSL Drivers Multimedia Broadcast Systems Professional Video Cameras Video Amplifiers Copiers/Scanners/Fax HDTV Amplifiers Pulse Amplifiers and Peak Detectors CATV/Fiber Optics Signal Processing APPLICATION NOTES: PERFORMANCE DISCUSSION: The LM7171 is a very high speed, voltage feedback amplifier. It consumes only 6.5mA supply current while providing a gain-bandwidth product of 170MHz (Minimum) and a slew rate of 2000V/uS (Minumum). It also has other great features such as low differential gain and phase and high output current. The LM7171 is a true voltage feedback amplifier. Unlike current feedback amplifiers (CFAs) with a low inverting input impedance and a high non-inverting input impedance, both inputs of voltage feedback amplifiers (VFA's) have high impedance nodes. The low impedance inverting input in CFA's and a feedback capacitor create an additional pole that will lead to instability. As a result, CFA's cannot be used in traditional op amp circuits such as photodiode amplifiers, I-to-V converters and integrators, where a feedback capacitor is required. CIRCUIT OPERATION: The class AB input stage in the LM7171 is fully symmetrical and has a similar slewing characteristic to the current feedback amplifiers. In the LM7171 Simplified Schematic, (see AN00006) Q1 through Q4 form the equivalent of the current feedback input buffer, RE the equivalent of the feedback resistor, and stage A buffers the inverting input. The triple-buffered output stage isolates the gain stage from the load to provide low output impedance. 2 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 Applications (Continued) SLEW RATE CHARACTERISTIC: The slew rate of LM7171 is determined by the current available to charge and discharge an internal high impedance node capacitor. This current is the differential input voltage divided by the total degeneration resistor RE. Therefore, the slew rate is proportional to the input voltage level, and the higher slew rates are achievable in the lower gain configurations. See the LM7171 Commercial Data Book for slew rate Vs input voltage level curve. When a very fast, large signal, pulse is applied to the input of an amplifier, some overshoot or undershoot occurs. By placing an external resistor such as 1K Ohm in series with the input of the LM7171, the bandwidth is reduced to help lower the overshoot. SLEW RATE LIMITATION: If the amplifier's input signal has too large of an amplitude at too high of a frequency, the amplifier is said to be slew rate limited; this can cause ringing in time domain, and peaking in frequency domain, at the output of the amplifier. In the Commercial Data Book "Typical Performance Characteristics" section, there are several curves of Av = +2 and Av = +4 versus input power levels. For the Av = +4 curves, no peaking is present and the LM7171 responds identically to the different input power levels of 30 mV, 100 mV and 300mV. For the Av = +2 curves, slight peaking occurs. This peaking at high frequency (>100MHz) is caused by a large input signal at high enough frequency, that it exceeds the amplifier's slew rate. The peaking in frequency response does not limit the pulse response in time domain. The LM7171 is stable with noise gain of > +2. LAYOUT CONSIDERATION: PRINTED CIRCUIT BOARDS AND HIGH SPEED OP AMPS: There are many things to consider when designing PC boards for high speed op amps. Without proper caution, it is very easy to have excessive ringing, oscillation, and other degraded AC performance in high speed circuits. As a rule, the signal traces should be short and wide to provide low inductance and low impedance paths. Any unused board space must be grounded to reduce stray signal pickup. Critical components should also be grounded at a common point to eliminate voltage drop. Sockets add capacitance to the board and can affect high frequency performance. It is better to solder the amplifier directly into the PC board without using any socket. USING PROBES: Active (FET) probes are ideal for taking high frequency measurements because they have wide bandwidth, high input impedance, and low input capacitance. However, the probe ground leads provide a long ground loop that will produce errors in measurement. Instead, the probes can be grounded directly by removing the ground leads and probe jackets and using scope probe jacks. COMPONENT SELECTION & FEEDBACK RESISTOR: It is important in high speed applications to keep all component leads short. For discrete components, choose carbon composition-type resistors and mica-type capacitors. Surface mount components are preferred over discrete components for minimum inductive effect. Large values of feedback resistors can couple with parasitic capacitance and cause undesirable effects such as ringing or oscillation in high speed amplifiers. For LM7171, a feedback resistor of 510 Ohms gives optimal performance. COMPENSATION FOR INPUT CAPACITANCE: The combinations of an amplfier's input capacitance with the gain setting resistors adds a pole that can cause peaking or oscillation. To solve this problem, a feedback capacitor with a value Cf>(Rg X Cin)/Rf can be used to cancel that pole. For LM7171, a feedback capacitor of 2pF is recommended. AN00003 illustrates the compensation circuit. POWER SUPPLY BYPASSING: Bypassing the power supply is necessary to maintain low power supply impedance across the frequency spectrum. Both positive and negative power supplies should be bypassed individually by placing 0.01uF ceramic capacitors directly to the power supply pins and 2.2uF tantalum capacitors close to the power supply pins. See AN00004. TERMINATION: In high frequency applications, reflection occur if signals are not properly terminated. Figure 3, in the Commercial Data Book, shows a properly terminated signal, while Figure 4, in the Commercial Data Book, shows an improperly terminated signal. To minimize reflection, coaxial cable with matching characteristic impedance to the signal source should be used. The other end of the cable should be terminated with the same value terminator or resistor. For the commonly used cables, RG59 has 75 Ohm characteristic impedance, and RG58 has 50 Ohm characteristic impedance. 3 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 Applications (Continued) DRIVING CAPACITIVE LOADS: Amplifiers driving capactive loads can oscillate or have ringing at the output. To eliminate oscillation or reduce ringing, an isolation resistor can be placed as shown on AN00005. The combination of the isolation resistor and the load capacitor forms a pole to increase stability by adding more phase margin to the overall system. The desired performance depends upon the value of the isolation resistor; the bigger the isolation resistor, the more damped the pulse response becomes. For LM7171, a 50 Ohm isolation resistor is recommended for initial evaluation. Figure 6, in the Commercial Data Book, shows the LM7171 driving a 150pF load with the 50 Ohm isolation resistor. POWER DISSIPATION: The maximum power allowed to dissipate in a device is defined as: Pd = [Tj(max) - TA]/ThetaJA, where Pd (is the power dissipation in a device), Tj(max) (is the maximum junction temperature), TA (is the ambient temperature), ThetaJA (is the thermal resistance of a particular package). For example, for the LM7171 in a J-8 package, the maximum power dissipation at 25 C ambient temperature is 730mW. The total power dissipation in a device can be calculated as: Pd = Pq + Pl Pq is the quiescent power dissipated in a device with no load connected at the output. Pl is the power dissipated in the device with a load connected at the output; it is not the power dissipated by the load. Furthermore, Pq = supply current x total supply voltage with no load, Pl = output current x (voltage difference between supply voltage and output voltage of the same side of supply voltage). For example, the total power dissipated by the LM7171 with Vs = <15V and output voltage of 10V into 1K Ohm is: Pd = Pq + Pl = (6.5mA)x(30V)+(10mA)x(15V - 10V) = 195mW + 50mW = 245mW 4 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 (Absolute Maximum Ratings) (Note 1) Supply Voltage (V+ - V-) 36V Differential Input Voltage (Note 6) +10V Maximum Junction Temperature 150 C Maximum Power Dissipation (Note 2, 3) 730mW Output Short Circuit to Ground (Note 4) Continuous Operating Temperature Range -55 C < Ta < +125 C Thermal Resistance (Note 7) ThetaJA 8-Pin CERAMIC DIP (Still Air) (500LF/Min Air flow) 10-Pin CERPAK (Still Air) (500LF/Min Air flow) 10-Pin CERAMIC SOIC (Still Air) (500LF/Min Air flow) ThetaJC (Note 3) 8-Pin CERAMIC DIP 10-Pin CERPAK 10-Pin CERAMIC SOIC Package Weight (Typical) 8-Pin CERAMIC DIP 10-Pin CERPAK 10-Pin CERAMIC SOIC Storage Temperature Range 106 53 182 105 182 105 C/W C/W C/W C/W C/W C/W 3 C/W 5 C/W 5 C/W 965mg 235mg 230mg -65 C < Ta < +150 C ESD Tolerance (Note 5) 3000V Note 1: Note 2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test conditions. The maximum power dissipation must be derated at elevated temperatures and is dictated by Tjmax (maximum junction temperature), ThetaJA (package junction to ambient thermal resistance), and TA (ambient temperature). The maximum allowable power dissipation at any temperature is Pdmax = (Tjmax - TA)/ThetaJA or the number given in the Absolute Maximum Ratings, whichever is lower. 5 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 (Continued) Note 3: Note 4: Note 5: Note 6: Note 7: The package material for these devices allows much improved heat transfer over our standard ceramic packages. In order to take full advantage of this improved heat transfer, heat sinking must be provided between the package base (directly beneath the die), and either metal traces on, or thermal vias through, the printed circuit board. Without this additional heat sinking, device power dissipation must be calculated using junction-to-ambient, rather than junction-to-case, thermal resistance. It must not be assumed that the device leads will provide substantial heat transfer out of the package, since the thermal resistance of the leadframe material is very poor, relative to the material of the package base. The stated junction-to-case thermal resistance is for the package material only, and does not account for the additional thermal resistance between the package base and the printed circuit board. The user must determine the value of the additional thermal resistance and must combine this with the stated value for the package, to calculate the total allowed power dissipation for the device. Applies to both single-supply and split-supply operation. Continuous short circuit operation at elevated ambient temperature can result in exceeding the maximum allowed junction temperature of 150 C. Human body model, 1.5k Ohms in series with 100pF. Input differential voltage is measured at Vs = +15V. All numbers apply for packages soldered directly into a PC board. Recommended Operating Conditions (Note 1) Supply Voltage 5.5V < V+ < 36V Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test conditions. 6 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 Electrical Characteristics DC PARAMETERS: +15V (See NOTE 6) (The following conditions apply to all the following parameters, unless otherwise specified.) DC: V+ = +15V, V- = -15V, Vcm = 0V, and Rl > 1M Ohm SYMBOL Vio +Iib -Iib Iio CMRR PSRR Av PARAMETER CONDITIONS NOTES 7 mV 2, 3 10 uA 1 12 uA 2, 3 10 uA 1 12 uA 2, 3 4 uA 1 6 uA 2, 3 85 dB 1 70 dB 2, 3 85 dB 1 80 dB 2, 3 1 80 dB 1 1 75 dB 2, 3 1 75 dB 1 1 70 dB 2, 3 Input Offset Current Large Signal Voltage Gain Vcm = +10V Vs = +15V to +5V Rl = 1K Ohm, Vout = +5V Output Swing Output Current (Open Loop) Rl = 1K Ohm Sourcing, Rl = 100 Ohms Sinking, Rl = 100 Ohms Supply Current 7 SUBGROUPS 1 Input Bias Current Power Supply Rejection Ratio UNIT mV Input Bias Current Common Mode Rejection Ratio MAX 1 Rl = 100 Ohms Is MIN Input Offset Voltage Rl = 100 Ohms, Vout = +5V Vo PINNAME 13 -13 V 1 12.7 -12.7 V 2, 3 10.5 -9.5 V 1 9.5 -9 V 2, 3 2 105 mA 1 2 95 mA 2, 3 2 -95 mA 1 2 -90 mA 2, 3 8.5 mA 1 9.5 mA 2, 3 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 Electrical Characteristics AC PARAMETERS: +15V (See NOTE 6) (The following conditions apply to all the following parameters, unless otherwise specified.) AC: V+ = +15V, V- = -15V, Vcm = 0V SYMBOL PARAMETER Sr Slew Rate Gbw Unity-Gain Bandwidth CONDITIONS NOTES Av = 2, Vin = +2.5V, 3nS Rise & Fall time PINNAME MIN MAX UNIT SUBGROUPS 3, 4 2000 V/uS 4 5 170 MHz 4 1.5 mV 1 7 mV 2, 3 10 uA 1 12 uA 2, 3 10 uA 1 12 uA 2, 3 4 uA 1 6 uA 2, 3 80 dB 1 70 dB 2, 3 1 75 dB 1 1 70 dB 2, 3 1 72 dB 1 1 67 dB 2, 3 DC PARAMETERS: +5V (See NOTE 6) (The following conditions apply to all the following parameters, unless otherwise specified.) DC: Tj = 25 C, V+ = +5V, V- = -5V, Vcm = 0V, and Rl > 1M Ohm Vio +Iib -Iib Iio CMRR Av Input Offset Voltage Input Bias Current Input Bias Current Input Offset Current Common Mode Rejection Ratio Large Signal Voltage Gain Vcm = +2.5V Rl = 1K Ohm, Vout = +1V Rl = 100 Ohms, Vout = +1V Vo Output Swing Rl = 1K Ohm Rl = 100 Ohms Output Current (Open Loop) Sourcing, Rl = 100 Ohms Sinking, Rl = 100 Ohms Is Supply Current 8 3.2 -3.2 V 1 3.0 -3.0 V 2, 3 2.9 -2.9 V 1 2.8 -2.75 V 2, 3 2 29 mA 1 2 28 mA 2, 3 2 -29 mA 1 2 -27.5 mA 2, 3 8 mA 1 9 mA 2, 3 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 Electrical Characteristics DC PARAMETERS: +15V, DRIFT VALUES (See NOTE 6) (The following conditions apply to all the following parameters, unless otherwise specified.) DC: Tj = 25 C, V+ = +15V, V- = -15V, Vcm = 0V, and Rl > 1M Ohm. "Delta calculations performed on JAN S and QMLV devices at Group B, subgroup 5 only." SYMBOL PARAMETER CONDITIONS NOTES PINNAME MIN MAX UNIT SUBGROUPS Vio Input Offset Voltage -250 250 uV 1 +Ibias Input Bias Current -500 500 nA 1 -Ibias Input Bias Current -500 500 nA 1 DC PARAMETERS: +5V, DRIFT VALUES (See NOTE 6) (The following conditions apply to all the following parameters, unless otherwise specified.) DC: Tj = 25 C, V+ = +5V, V- = -5V, Vcm = 0V, and Rl > 1M Ohm. "Delta calculations performed on JAN S and QMLV devices at Group B, subgroup 5 only." Vio Input Offset Voltage -250 250 uV 1 +Ibias Input Bias Current -500 500 nA 1 -Ibias Input Bias Current -500 500 nA 1 Note 1: Note 2: Note Note Note Note 3: 4: 5: 6: Large signal voltage gain is the total output swing divided by the input signal required to produce that swing. For Vs = +15V, Vout = +5V. For Vs = +5V, Vout = +1V. The open loop output current is guaranteed, by the measurement of the open loop output voltage swing, using 100 Ohms output load. See AN00001 for Sr test circuit. Slew Rate measured between +4V. See AN00002 for Gbw test circuit. Pre and post irradiation limits are identical to those listed under AC and DC electrical characteristics except as listed in the Post Radiation Limits Table. These parts may be dose rate sensitive in a space environment and demonstrate enhanced low dose rate effect. Radiation end point limits for the noted parameters are guaranteed only for the conditions as specified in MIL-STD-883, Method 1019.5 9 MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 Graphics and Diagrams GRAPHICS# DESCRIPTION 05885HRA4 CERDIP (J), 8 LEAD (B/I CKT) 06344HRA1 CERAMIC SOIC (WG, W), 10 LEAD (B/I CKT) AN00001A SLEWRATE TEST CKT AN00002A CBW TEST CKT AN00003A COMPENSATING FOR INPUT CAPACITANCE AN00004A POWER SUPPLY BYPASSING AN00005A ISOLATION RESISTOR TO DRIVE CAPACITIVE LOAD AN00006A SIMPLIFIED SCHEMATIC DIAGRAM J08ARL CERDIP (J), 8 LEAD (P/P DWG) P000029B CERDIP (J), 8 LEAD (PIN OUT) P000157A CERAMIC SOIC (WG), 10 LEAD (PINOUT) P000170A CERPACK (W), 10 LEAD (PINOUT) W10ARG CERPACK (W), 10 LEAD (P/P DWG) WG10ARC CERAMIC SOIC (WG), 10 LEAD (P/P DWG) See attached graphics following this page. 10 NC 1 10 NC IN- 2 9 V+ NC 3 8 NC IN+ 4 7 VOUTPUT V- 5 6 NC LM7171AMWG 10 - LEAD CERAMIC SOIC CONNECTION DIAGRAM TOP VIEW P000157A N MIL/AEROSPACE OPERATIONS 2900 SEMICONDUCTOR DRIVE SANTA CLARA, CA 95050 N MICROCIRCUIT DATA SHEET MNLM7171AM-X-RH REV 0B0 Revision History Rev ECN # Originator Changes 0A0 M0003645 08/31/00 Rel Date Rose Malone Initial MDS Release: MNLM7171AM-X-RH, Rev. 0A0 0B0 M0003729 08/31/00 Rose Malone Update MDS: MNLM7171AM-X-RH, Rev. 0A0 to MNLM7171AM-X-RH, Rev. 0B0. Changed Main Table and Features Section reference to Rad Hard NS Part Numbers and 5962 SMD Drawings for J Pkg and WG Pkg. Changed from RQML, RQMLV, 5962R9553601QPA, VPA, QXA, VXA to FQML, FQMLV, 5962F9553601QPA, VPA, QXA, VXA. Rad Hard Level 100K to 300K. 11