LF147 NSC | Alldatasheet

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Features

n Internally trimmed offset voltage: 5 mV max n Low input bias current: 50 pA n Low input noise current: n Wide gain bandwidth: 4 MHz n High slew rate: 13 V/µs n Low supply current: 7.2 mA n High input impedance: 1012Ω n Low total harmonic distortion AV =10,: <0.02% R L=10k, VO =20 Vp-p, BW=20 Hz−20 kHz n Low 1/f noise corner: 50 Hz n Fast settling time to 0.01% :2 µ s Simplified Schematic Connection Diagram BI-FET II™ is a trademark of National Semiconductor Corporation. 1⁄4 Quad DS005647-13 Dual-In-Line Package DS005647-1 Note 1:Available per SMD#8102306, JM38510/11906. Top View Order Number LF147J, LF347M, LF347BN, LF347N or LF147J/883(Note 1) See NS Package Number J14A, M14A or N14A May 1999 LF147/LF347 Wide Bandwidth Quad JFET Input Operational Amplifiers © 1999 National Semiconductor Corporation DS005647 www.national.com

Absolute Maximum Ratings(Note 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. LF147 LF347B/LF347 Supply Voltage ±22V ±18V Differential Input Voltage ±38V ±30V Input Voltage Range ±19V ±15V (Note 3) Output Short Circuit Continuous Continuous Duration (Note 4) Power Dissipation 900 mW 1000 mW (Notes 5, 11) Tjmax 150˚C 150˚C θjA Ceramic DIP (J) Package 70˚C/W Plastic DIP (N) Package 75˚C/W Surface Mount Narrow (M) 100˚C/W LF147 LF347B/LF347 Surface Mount Wide (WM) 85˚C/W Operating Temperature (Note 6) (Note 6) Range Storage Temperature Range −65˚C ≤T A≤150˚C Lead Temperature (Soldering, 10 sec.) 260˚C 260˚C Soldering Information Dual-In-Line Package Soldering (10 seconds) 260˚C Small Outline Package Vapor Phase (60 seconds) 215˚C Infrared (15 seconds) 220˚C See AN-450 “Surface Mounting Methods and Their Effect on Product Reliability” for other methods of soldering surface mount devices. ESD Tolerance (Note 12) 900V Symbol Parameter Conditions LF147 LF347B LF347 Units Min Typ Max Min Typ Max Min Typ Max VOS Input Offset Voltage R S =10 kΩ ,TA =25˚C 1 5 3 5 5 10 mV Over Temperature 8 7 13 mV ΔVOS /ΔT Average TC of Input Offset R S =10 kΩ 10 10 10 µV/˚C Voltage IOS Input Offset Current T j=25˚C, (Notes 7, 8) 25 100 25 100 25 100 pA Over Temperature 25 4 4 nA IB Input Bias Current T j=25˚C, (Notes 7, 8) 50 200 50 200 50 200 pA Over Temperature 50 8 8 nA R IN Input Resistance T j=25˚C 10 12 1012 1012 Ω AVOL Large Signal Voltage Gain V S =±15V, TA =25˚C 50 100 50 100 25 100 V/mV VO =±10V, RL=2k Ω Over Temperature 25 25 15 V/mV VO Output Voltage Swing V S =±15V, RL=10 kΩ ±12 ±13.5 ±12 ±13.5 ±12 ±13.5 V VCM Input Common-Mode Voltage V S =±15V ±11 +15 ±11 +15 ±11 +15 V Range −12 −12 −12 V CMRR Common-Mode Rejection Ratio R S≤10 kΩ 80 100 80 100 70 100 dB PSRR Supply Voltage Rejection Ratio (Note 9) 80 100 80 100 70 100 dB I S Supply Current 7.2 11 7.2 11 7.2 11 mA www.national.com 2

Symbol Parameter Conditions LF147 LF347B LF347 Units Min Typ Max Min Typ Max Min Typ Max Amplifier to Amplifier Coupling T A =25˚C, −120 −120 −120 dB f=1 Hz−20 kHz (Input Referred) SR Slew Rate V S =±15V, TA =25˚C 8 13 8 13 8 13 V/µs GBW Gain-Bandwidth Product V S =±15V, TA =25˚C 2.2 4 2.2 4 2.2 4 MHz en Equivalent Input Noise Voltage T A =25˚C, RS =100Ω , 2 02 02 0 f=1000 Hz in Equivalent Input Noise Current T j=25˚C, f=1000 Hz 0.01 0.01 0.01 Note 2:Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is func- tional, but do not guarantee specific performance limits. Note 3:Unless otherwise specified the absolute maximum negative input voltage is equal to the negative power supply voltage. Note 4:Any of the amplifier outputs can be shorted to ground indefinitely, however, more than one should not be simultaneously shorted as the maximum junction temperature will be exceeded. Note 5:For operating at elevated temperature, these devices must be derated based on a thermal resistance ofθjA. Note 6:The LF147 is available in the military temperature range −55˚C≤TA≤125˚C, while the LF347B and the LF347 are available in the commercial temperature range 0˚C≤TA≤70˚C. Junction temperature can rise to Tjmax = 150˚C. Note 7:Unless otherwise specified the specifications apply over the full temperature range and for VS =±20V for the LF147 and for VS =±15V for the LF347B/LF347. VOS ,IB, and IOS are measured at VCM =0. Note 8:The input bias currents are junction leakage currents which approximately double for every 10˚C increase in the junction temperature, Tj. Due to limited pro- duction test time, the input bias currents measured are correlated to junction temperature. In normal operation the junction temperature rises above the ambient tem- perature as a result of internal power dissipation, PD .Tj=TA+θjAPD where θjAis the thermal resistance from junction to ambient. Use of a heat sink is recommended if input bias current is to be kept to a minimum. Note 9:Supply voltage rejection ratio is measured for both supply magnitudes increasing or decreasing simultaneously in accordance with common practice from VS = ± 5V to±15V for the LF347 and LF347B and from VS = ±20V to±5V for the LF147. Note 10:Refer to RETS147X for LF147D and LF147J military specifications. Note 11:Max. Power Dissipation is defined by the package characteristics. Operating the part near the Max. Power Dissipation may cause the part to operate out- side guaranteed limits. Note 12:Human body model, 1.5 kΩ in series with 100 pF. www.national.com3

Typical Performance Characteristics Input Bias Current DS005647-14 Input Bias Current DS005647-15 Supply Current DS005647-16 Positive Common-Mode Input Voltage Limit DS005647-17 Negative Common-Mode Input Voltage Limit DS005647-18 Positive Current Limit DS005647-19 Negative Current Limit DS005647-20 Output Voltage Swing DS005647-21 Output Voltage Swing DS005647-22 www.national.com 4

Typical Performance Characteristics(Continued) Gain Bandwidth DS005647-23 Bode Plot DS005647-24 Slew Rate DS005647-25 Distortion vs Frequency DS005647-26 Undistorted Output Voltage Swing DS005647-27 Open Loop Frequency Response DS005647-28 Common-Mode Rejection Ratio DS005647-29 Power Supply Rejection Ratio DS005647-30 Equivalent Input Noise Voltage DS005647-31 www.national.com5

Typical Performance Characteristics(Continued) Open Loop Voltage Gain DS005647-32 Output Impedance DS005647-33 Inverter Settling Time DS005647-34 www.national.com 6

Pulse Response R L=2k Ω ,C L=10 pF Application Hints The LF147 is an op amp with an internally trimmed input off- set voltage and JFET input devices (BI-FET II). 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 ac- commodated without a large increase in input current. The maximum differential input voltage is independent of the sup- ply voltages. However, neither of the input voltages 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 re- versal of phase to the output. Exceeding the negative common-mode limit on both inputs will force the amplifier output to a high state. In neither case does a latch occur since raising the input back within the common-mode range again puts the input stage and thus the amplifier in a normal operating mode. Small Signal Inverting DS005647-4 Small Signal Non-Inverting DS005647-5 Large Signal Inverting DS005647-6 Large Signal Non-Inverting DS005647-7 Current Limit (RL=100Ω ) DS005647-8 www.national.com7

Application Hints(Continued) Exceeding the positive common-mode limit on a single input will not change the phase of the output; however, if both in- puts 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 gain 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 biased by a zener reference which allows normal circuit operation on ±4.5V power sup- plies. Supply voltages less than these may result in lower gain bandwidth and slew rate. The LF147 will drivea2k Ω load resistance to ±10V over the full temperature range. If the amplifier is forced to drive heavier 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 supply for the integrated circuit never becomes reversed in polarity or that the unit is not inadvertently installed backwards in a socket as an unlimited current surge through the resulting forward diode within the IC could cause fusing of the internal conductors and result in a destroyed unit. As with most amplifiers, care should be taken with lead dress, component placement and supply decoupling in order to ensure stability. For example, resistors from the output to an input should be placed with the body close to the input to minimize “pick-up” and maximize the frequency of the feed- back pole by minimizing the capacitance from the input to ground. A feedback pole is created when the feedback around any amplifier is resistive. The parallel resistance and capacitance from the input of the device (usually the inverting input) 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 feed- back pole is less than approximately 6 times the expected 3 dB frequency a lead capacitor should be placed from the out- put to the input of the op amp. The value of the added ca- pacitor should be such that the RC time constant of this ca- pacitor and the resistance it parallels is greater than or equal to the original feedback pole time constant. Detailed Schematic DS005647-9 www.national.com 8

Digitally Selectable Precision Attenuator DS005647-10 All resistors 1% tolerance

  • Accuracy of better than 0.4% with standard 1% value resistors
  • No offset adjustment necessary
  • Expandable to any number of stages
  • Very high input impedance A1 A2 A3 V O Attenuation 000 0 0 0 1 −1 dB 0 1 0 −2 dB 0 1 1 −3 dB 1 0 0 −4 dB 1 0 1 −5 dB 1 1 0 −6 dB 1 1 1 −7 dB www.national.com9

Typical Applications(Continued) Long Time Integrator with Reset, Hold and Starting Threshold Adjustment DS005647-11

  • VOUT starts from zero and is equal to the integral of the input voltage with respect to the threshold voltage:
  • Output starts when VIN≥VTH
  • Switch S1 permits stopping and holding any output value
  • Switch S2 resets system to zero www.national.com 10

Typical Applications(Continued) Universal State Variable Filter DS005647-12 For circuit shown: fo=3 kHz, fNOTCH =9.5 kHz Q =3.4 Passband gain: Highpass — 0.1 Bandpass — 1 Lowpass — 1 Notch — 10

  • foxQ ≤200 kHz
  • 10V peak sinusoidal output swing without slew limiting to 200 kHz
  • See LM148 data sheet for design equations www.national.com11

Physical Dimensionsinches (millimeters) unless otherwise noted Ceramic Dual-In-Line Package (J) Order Number LF147J or LF147J/883 S.O. Package (M) Order Number LF347M www.national.com 12

Physical Dimensionsinches (millimeters) unless otherwise noted (Continued) 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. National Semiconductor Corporation Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: support@nsc.com National Semiconductor Europe Fax: +49 (0) 1 80-530 85 86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 1 80-530 85 85 English Tel: +49 (0) 1 80-532 78 32 Français Tel: +49 (0) 1 80-532 93 58 Italiano Tel: +49 (0) 1 80-534 16 80 National Semiconductor Asia Pacific Customer Response Group Tel: 65-2544466 Fax: 65-2504466 Email: sea.support@nsc.com National Semiconductor Japan Ltd. Tel: 81-3-5639-7560 Fax: 81-3-5639-7507 www.national.com Molded Dual-In-Line Package (N) Order Number LF347BN or LF347N LF147/LF347 Wide Bandwidth Quad JFET Input Operational Amplifiers National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.