NATL SEMICOND (LINEAR) 22E D MM &501124 007401 3 Mm National Semiconductor LF147/LF347/LF347B Wide Bandwidth Quad JFET Input Operational Amplifiers General Description The LF147 Is a low cost, high speed quad JFET input opera- tional amplifier with an internally trimmed input offset volt- age (BI-FET IIT technology). The device requires a low supply current and yet maintains a large gain bandwidth product and a fast slew rate. In addition, well matched high voltage JFET input devices provide very low input blas and offset currents. The LF147 is pin compatible with the stan- dard LM148, This feature allows designers to immediately Features @ Internally trimmed offset voltage @ Low input bias current @ Low input noise current m Wide gain bandwidth B High slew rate m@ Low supply current # High input impedance 8L-FET H Technology 7-79 1S 5 mV max 50 pA 0.01 pA/VHz 4 MHz 13 V/ys 7.2 mA 10120 upgrade the overall performance of existing LF148 and Low total harmonic distortion Ay= 10, <0.02% LM124 designs, RL= 10k, Vo=20 Vp-p, BW=20 Hz20 kHz The LF147 may be used In applications such as high speed + Low 1/f noise corner 50 Hz integrators, fast D/A converters, sample-and-hold circuits | Fast settling time to 0.01% 2 ys and many other circuits requiring low Input offset voltage, low input bias current, high Input impedance, high slew rate and wide bandwidth. The device has low noise and offset voltage drift, Simplified Schematic Connection Diagram Y, Quad Dual-In-Line Package Vee O= ouT = INa~ In at v- in3t w3-aUT3 14 13 2 53] Ww | 8 8 Vo INTERNALLY |! 2 3 4 5 & ? INTERNALLY ; TRIMMED TRIMMED ourt int Intt vt IN2 IN2- QUT2 Vee O= : o TL/H/S6471 TL/H/5847-13 Top View Order Number LF147D, LF347D, LF147J, LF347Bu, LF347J, LF347M, LF347WM, LF347BN or LF347N See NS Package Number D14E, J14A, M14A, adres V/2Pes 1/2 M148 or N14A 3-15NATL SEMZCOND (LINEAR) LF147/LF347/LF347B 22E D M@ 6501124 oOb7902 5 mm Absolute Maximum Ratings If Milltary/Aerospace specified devices are required, LF147 LF347B/LF347 please contact the Natlonal Semiconductor Sales Operating Temperature (Note 4) (Note 4) Office/Distributors for avallability and specifications. Range F147 LF347B/LF347 Storage Temperature Supply Voltage 22V 18V Range 65C <Ta< 160C Differential Input Voltage 38V +30V Lead Temperature Input Voltage Range 19V +15V (Soldering, 10 sec.) 260C 260C (Note 1) Soldering Information Output Short Circuit Continuous Continuous Dual-In-Line Package Duration (Note 2) Soldering (10 seconds) 260C Power Dissipation 900 mW 1000 mw Small Outline Package (Notes 3 ond 9) m om Vapor Phase (60 seconds) 215C Tmax 160C 150C Infrared (15 seconds) 220C 6 A See AN-450 Surface Mounting Methods and Their Effect "Savity DIP (D) Package 80C/W on Preduct Reliability for other methods of soldering sur- Ceramic DIP (J) Package 70C/W face mount devices. Plastic DIP (N) Package 72C/W ESD rating to be determined. Surface Mount Narrow (M) 100C/W Surface Mount Wide (WM) 85C/W DC Electrical Characteristics (notes) Symbol Parameter Conditions L147 LF347B LF347 Units Min} Typ |Max| Min} Typ |Max| Min| Typ |Max Vos Input Offset Voltage Rg= 10 kf, Ta=28C 1 5 3 5 5 10] mv Over Temperature 8 7 13 | mV AVas/ AT} Average TC of Input Offset Rg= 10k 10 10 10 pViG Voltage los Input Offset Current Tj=25C, (Notes 5, 6) 25 | 100 26 |100 25 4100] pA Over Temperature 26 4 4 nA 2) Input Bias Current Tj=25C, (Notes 5, 6) 50 | 200 50 | 200 50 | 200] pA Over Temperature 50 8 8 nA Rin Input Resistance Tj=25C 1012 1012 1012 a AVoL Large Signal Voltage Gain Vg= 15V, Ta=25C | 50 | 100 50 | 100 25 | 100 V/mV Vo= 10V, Rp =2k0 Over Temperature 25 25 15 V/mV Vo Output Voltage Swing Vg= + 16V, Rp=10 kM) +12) 13.65 12] 13.5 12} 13.5 v Vom Input Common-Mode Voltage = +16 +16 +16 v Range Vg= 15V #11) 45 11) 49 11} 40 v CMRR_ |Common-Mode Rejection Ratio] Ag < 10 kn 80 | 100 80 | 100 70 | 100 dB PSRR Supply Voitage Rejection Ratio | (Note 7) 80 | 100 680 | 100 70 | 100 dB Is Supply Current 7.2 | 11 7.2 1 11 7.2 | 11) mANATL SEMICOND (LINEAR) ecE D MM 6501124 0067503 7 om AC Electrical Characteristics (notes) T-79-15 Symboi Parameter Conditions LF147 LFS47B LF347 Units Min| Typ | Max|Min| Typ |Max| Min} Typ | Max Amplifier to Amplifier Coupling | Ta=25C, 120 120 ~-120 dB f=1Hz20 kHz (Input Referred) SR Slew Rate Ve= 15V,Ta=25'C| 8 | 13 8 | 13 8 | 13 V/s QBW | Gain-Bandwidth Product Vg= 16V, Ta=25C| 2.2] 4 22] 4 22) 4 MHz 6 Equivalent Input Nolse Voltage | Ta= 25C, Rg= 1000, 20 20 20 nV/VHz f= 1000 Hz ln Equivalent input Nolse Current | T}=25C, f= 1000 Hz 0.01 0.01 0.01 pA/VHz Note 1: Unieas otherwise specified the absolute maximum negative Input voltage Is equal to the negative power supply voltage, tamparafure will be exceeded, Note 3: For oparating at elevated temperature, these devices must be derated based on a thermal reslatance of A. range O'C<T,<70C, Junction temperature can rige to Ty max = 180C, LF347, Vog, Ig, and log are measured at Vorg=0, fecommended if Input blas. current ts to be kept to a minimum. Vg = + 6V to 15V for the LF947 and LF947B and from Vg = 20V to 5V for the LF147. Note 6; Refer to RETS147X for LF147D and LF147u military specifications, outside guaranteed limits, Note 2: Any of the amplifier outauts can be shorted to ground Iadefinitely, however, more than one should not be simultaneously shorted as the maximum function Note 4: The LF147 Is avaliable In the military temperature fange ~55C< Tas 128C, while the LF247B and the LF347 are available In the commercial temperature Note 6: Unies otharwise specified the specifications apply over the full temperature range and for Vg = + 20V for the LF147 and for Vg = 18 for the LF9478/ Note 6: The input blas currents are junction leakage currents which approximately double for every 10C Increase In the junction temperature, Tj. Dua to ilmited production test time, the Input blas currants measured are correlated to lunction temperature. In normal operation the Junction temperature rises above the ambient tomperature as a reault of Internal power dissipation, Pp. T}=Ta+ a Pp where 4, is the thermal resistance from junction to amblent. Use of a heat sink Is Note 7: Supply voltage rejection ratio is measured for bath supply magnitudes [r Ing or d g al busty in with common practice from Note 9: Max. Power Dissipation Is defined by the package characteristics. Operating the part near the Max. Power Olssipation may cause the part to operate 3-17 apes T/ZbesV/Zbb 1NATL SEMICOND (LINEAR) LF147/LF347/LF347B eee D Mm 6501124 OOL7904 9 Typical Performance Characteristics {Input Blas Current 108 Ts gn a 3a 3 a En 9 -10 <5 Q 5 10 COMMON-MODE VOLTAGE (V) Positive Common-Mode s Input Voltage Limit Be a4 z a5 us gE z= e 5 0 8 mm 2 POSITIVE SUPPLY VOLTAGE () Current Limit 15 @ = z 3 -19 2 Es o 8 E 6 n 2 0 4a QUTPUT SINK CURRENT (mA) Gain Bandwidth 6 55 5 46 4 UNITY GAIN BANDWIDTH (Witz) 38 3 -80 -25 0 2 80 78 100 126 TEMPERATURE (C) 10 Input Bias Current INPUT BIAS CURRENT (pA) Ss # 10 80-25 8 25 SO 7S 100 125 TEMPERATURE (*C) Negative Common-Mode Input Voltage Limit NESATIVE COMMON-MODE INPUT VOLTAGE LIMIT () 4 3s 6 -5 -10 ~15 -20 ~25 NEGATIVE SUPPLY VOLTAGE () Output Voltage Swing 50 =% 0 ga ge a =z ER 10 0 o 6 06 68 2 @ SUPPLY VOLTAGE (+) Bode Plo x t 190 a 100 = 16 60 ; 5 | ~10 af 2 108 - -1598 Ot 1 10 100 FREQUENCY (MHz) POSITIVE OUTPUT VOLTAGE SWING () SUPPLY CURRENT (mA) OUTPUT VOLTAGE SWING (Vp-p) SLEW RATE (/p3) T-79-15 e Supply Current G $s # 6 SUPPLY VOLTAGE (+ ) n 8 5 Positive Current Limit ' +15 9 2 4 4 QUTPUT SOURCE CURRENT (mA) "0 Output Voltage Swing 04 - 4 10 AL OUTPUT LOAD (kn) Slew Rate 0 ~8 ~25 0 2 S80 75 100 125 TEMPERATURE (C) TL/H/5647-2 3-18NATL SEMICOND (LINEAR) ecE D MM 4501124 0067905 0 my Distortion vs Frequency Ven t15 i Tax zee Fo Ay 100 pis wat 0.15 BISTORTION (3) a 100 tk 10k FREQUENCY (Hz) 0 10 100k Common-Mode Rejection Ratlo 18 10 mh on Ta < 14 - Vom F 100 CMAR= 20 LOG Yb OPEN ag $ a Yeu th 2 6 10 100 1k 10k 100k 1M 10M FREQUENCY (H2) Loop Voltage Gain OPEN LOOP VOLTAGE GAM (HY g 8 10 8 SUPPLY VOLTAGE () Typical Performance Characteristics (continued) Undistorted Output Voltage x Swing 22k Rh=26C Ay=1 OUTPUT VOLTAGE SWING (Vp-p) s 3 100k FREQUENCY (Hz) Power Supply Rejection Ratlo 10 Vs= 128 Th=we Et EE rs) 2 9 10 100 tk 10k 100k 1M FREQUENCY (Hz) 100 Output Impedance OUTPUT IMPEDANCE (0) 0 1k FREQUENCY (H2) 10k = 100k 1 T-79-15 Open Loop Frequency 0 Response 1 OPEN LOOP VOLTAGE GAIN (cB) 1 18 100 tk 10k 100k 1M 10M FREQUENCY (Hz) Equivalent Input Nolse nn Voltage ) Be 0 He = as a Bin 0 10 100k Ss 10K 100k FREQUENCY (Hz) Inverter Time 18 OUTPUT VOLTAGE SWING. FROM OY () o 04 1 SETTURG TIME (x8) TL/H/6647=-3 10 3-19 adpesT/Lees Zbl) EsNATL SEMICOND (LINEAR) LF147/LF347/LF347B ecE D MM &501124 0047906 2 Pulse Response pf, =2k0, .=10 pF Small Signat tnverting OUTPUT VOLTAGE SWING (50 mV/DtV) TIME (0.2 us/DIV) TLIH/5847=4 Large Signal Inverting OUTPUT VOLTAGE SWING (5V/DIV) OUTPUT VOLTAGE SWING (1V/DIV) T-79-15 Small Signal Non-Inverting OUTPUT VOLTAGE SWING (50 mV/DIV) TIME (0.2 us/DtV) TL/H/5647-5 Large Signal Non-Inverting OUTPUT VOLTAGE SWING (5V/DIV) TL/H/5647-7 TIME (5 ys/D1V) Application Hints The LF147 fs an op amp with an internally trimmed input offset voltage and JFET input devices (BI-FET IITM). These JFETs have large reverse breakdown voltages from gate to source and drain eliminating the need for clamps across the inputs, Therefore, large differential Input voltages can easily be accommodated without a large increase in input current. The maximum differential input voltage is independent of the supply voltages. However, neither of the input voltages TL/H/6647-8 should be allowed to exceed the negative supply as this will cause large currents to flow which can result in a destroyed unit. Exceeding the negative common-mode limit on either input will force the output to a high state, potentially causing a reversal of phase to the output. Exceeding the negative common-mode limit on both inputs will force the amplifier 3-20NATL SEMICOND (LINEAR) ece D 7 Application Hints (continuea) output to a high state. In neither case does a latch occur since ralsing the input back within the common-mode range again puts the Input stage and thus the amplifier In a normal operating mode, Exceeding the positive common-mode limit on a single input will not change the phase of the output; however, if both inputs exceed the limit, the output of the amplifier will be forced to a high state. The amplifiers will operate with a common-mode Input volt- age equal to the positive supply; however, the galn band- width and slew rate may be decreased In this condition. When the negative common-mode voltage swings to within 3V of the negative supply, an increase in input offset voltage may occur. Each amplifier Is individually blased by a zener reference which allows normal circuit operation on +4.5V power sup- plies. Supply voltages less than these may result in lower galn bandwidth and slew rate. The LF147 will drive a 2 kf. load resistance to +10V over the full temperature range. If the amplifier is forced to drive havier load currents, however, an Increase In input offset voltage may occur on the negative voltage swing and finally reach an active current limit on both positive and negative swings. Precautions should be taken to ensure that the power sup- ply for the integrated circult never becomes reversed in po- larity or that the unit Is not inadvertently installed back- T-79-15 wards in a socket as an unlimited current surge through the resulting forward dicde within the !C could cause fusing of the internal conductors and result in a destroyed unit, Because these amplifiers ar JFET rather than MOSFET input op amps they do not require special handling. As with most amplifiers, care should be taken with lead dress, component placement and supply decoupling in or- der to ensure stability, For example, resistors from the out- put to an input should be placed with the body close to the Input to minimize pick-up and maximize the frequency of the feedback pole by minimizing the capacitance from the input to ground. A feedback pola is created when the feedback around any amplifier is resistive. The parallel resistance and capacl- tance from the Input of the device (usually the inverting in- put) to AC ground set the frequency of the pole. In many instances the frequency of this pole is much greater than the expected 3 dB frequency of the closed loop gain and consequently there is negligible effect on stability margin. However, if the feedback pole is less than approximately 6 times the expected 3 dB frequency a lead capacitor should be placed from the output to the input of the op amp. The value of the added capacitor should be such that the RC time constant of this capacitor and the resistance it parallels is greater than or equal to the originat feedback pole time constant. M@@ 6501124 0067907 4 Detailed Schematic Ye O= e az as au 3 Oo > be $i su ook ara > 2 20k yar Quy ag A Ge s RB Ya 23 ae yt" TL/H/5647-9 3-21 elves 1/2h8s/ Zr= > LF147/LF347/LF347B = * SEMICOND (LINEAR) ecE D MM 6501124 0067908 & T-79-15 Typical Applications Digitally Selectable Precision Attenuator rH Ua Letae u am Ad) 3 tA LALA? We Hy, YA " 4 UGLEHT u A View 2 + uu Vs Vo Al A2 AS Attenuation 0 0 0 0 AYTERUATION S2LECT INPUTS 001 108 TL/H/6647-10 o 10 2dB Accuracy of better than 0.4% with standard 1% value resistors o 1 1 3dB No offset adjustment necessary +0 0 -4dB Expandable to any number of stages 101 ~dB Very high input impedance 11 =0 -6d8 1 1 1 -~7d8 Long Time Integrator with Reset, Hold and Starting Threshold Adjustment re to of | Ym OST THnesHoLe 1 OAM 19 vourace ih fm ie THAESHOLO ADAAT TUH/5647-11 Vour starts from zero and Is equal to the Integral of the Input voltage with respect to the threshold voltage: 1 Vour af ivi Veet Output starts when Viy2Vrq * Switch S1 permits stopping and holding any output value Switch S2 resets syatam to zero 4-22NATL SEMICOND (LINEAR) ece D Typical Applications (continues) Universat State Varlable Filter AAA T-79-15 Vv WA LEIA? 1 I Q OANDPASS 1% OUTPUT AAA vv HIGH PASS OUTUT For circuit shown: fo 3 kHz, fpoTcH=9.5 kHz Q=3.4 Passband gain: Highpass0.1 Bandpass1 Lowpass1 Notch10 fpXQS200 kHz 10V peak sinusoidal output swing without slew limiting to 200 kHz @ See LM148 data sheet for design equations M@@ 6501124 0067909 6 mm TL/H/5647~12 3-23 apes /LZpes/ Zbl cr