TL082Wide Bandwidth Dual JFET Input Operational AmplifierGeneral DescriptionThese devices are low cost, high speed, dual JFET input op-erational amplifiers with an internally trimmed input offsetvoltage (BI-FET II™ technology). They require low supplycurrent yet maintain a large gain bandwidth product and fastslew rate. In addition, well matched high voltage JFET inputdevices provide very low input bias and offset currents. TheTL082 is pin compatible with the standard LM1558 allowingdesigners to immediately upgrade the overall performance ofexisting LM1558 and most LM358 designs.

These amplifiers may be used in applications such as highspeed integrators, fast D/A converters, sample and hold cir-cuits and many other circuits requiring low input offset volt-age, low input bias current, high input impedance, high slewrate and wide bandwidth. The devices also exhibit low noiseand offset voltage drift.

Featuresn Internally trimmed offset voltage: 15 mVn Low input bias current: 50 pAn Low input noise voltage: 16nV/√Hzn Low input noise current: 0.01 pA/√Hzn Wide gain bandwidth: 4 MHzn High slew rate: 13 V/µsn Low supply current: 3.6 mAn High input impedance: 1012Ωn Low total harmonic distortion AV = 10,: <0.02%

RL = 10k, VO = 20 Vp − p,BW = 20 Hz−20 kHz

n Low 1/f noise corner: 50 Hzn Fast settling time to 0.01%: 2 µs

Typical Connection Connection Diagram

Simplified Schematic

BI-FET II™ is a trademark of National Semiconductor Corp.

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DIP/SO Package (Top View)

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Order Number TL082CM or TL082CPSee NS Package Number M08A or N08E

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April 1998

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Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,please contact the National Semiconductor Sales Office/Distributors for availability and specifications.

Supply Voltage ±18VPower Dissipation (Note 2)Operating Temperature Range 0˚C to +70˚CTj(MAX) 150˚CDifferential Input Voltage ±30V

Input Voltage Range (Note 3) ±15VOutput Short Circuit Duration ContinuousStorage Temperature Range −65˚C to +150˚CLead Temp. (Soldering, 10 seconds) 260˚CESD rating to be determined.Note 1: “Absolute Maximum Ratings” indicate limits beyond which damageto the device may occur. Operating Ratings indicate conditions for which thedevice is functional, but do not guarantee specific performance limits.

DC Electrical Characteristics (Note 5)

Symbol Parameter Conditions TL082C Units

Min Typ Max

VOS Input Offset Voltage RS = 10 kΩ, TA = 25˚C 5 15 mV

Over Temperature 20 mV

∆VOS/∆T Average TC of Input Offset RS = 10 kΩ 10 µV/˚C

Voltage

IOS Input Offset Current Tj = 25˚C, (Notes 5, 6) 25 200 pA

Tj ≤ 70˚C 4 nA

IB Input Bias Current Tj = 25˚C, (Notes 5, 6) 50 400 pA

Tj ≤ 70˚C 8 nA

RIN Input Resistance Tj = 25˚C 1012 ΩAVOL Large Signal Voltage Gain VS = ±15V, TA = 25˚C 25 100 V/mV

VO = ±10V, RL = 2 kΩOver Temperature 15 V/mV

VO Output Voltage Swing VS = ±15V, RL = 10 kΩ ±12 ±13.5 V

VCM Input Common-Mode Voltage VS = ±15V ±11 +15 V

Range −12 V

CMRR Common-Mode Rejection Ratio RS ≤ 10 kΩ 70 100 dB

PSRR Supply Voltage Rejection Ratio (Note 7) 70 100 dB

IS Supply Current 3.6 5.6 mA

AC Electrical Characteristics (Note 5)

Symbol Parameter Conditions TL082C Units

Min Typ Max

Amplifier to Amplifier Coupling TA = 25˚C, f = 1Hz- −120 dB

20 kHz (Input Referred)

SR Slew Rate VS = ±15V, TA = 25˚C 8 13 V/µs

GBW Gain Bandwidth Product VS = ±15V, TA = 25˚C 4 MHz

en Equivalent Input Noise Voltage TA = 25˚C, RS = 100Ω, 25 nV/√Hz

f = 1000 Hz

in Equivalent Input Noise Current Tj = 25˚C, f = 1000 Hz 0.01 pA/√Hz

Note 2: For operating at elevated temperature, the device must be derated based on a thermal resistance of 115˚C/W junction to ambient for the N package.

Note 3: Unless otherwise specified the absolute maximum negative input voltage is equal to the negative power supply voltage.

Note 4: The power dissipation limit, however, cannot be exceeded.

Note 5: These specifications apply for VS = ±15V and 0˚C ≤TA ≤ +70˚C. VOS, IB and IOS are measured at VCM = 0.

Note 6: The input bias currents are junction leakage currents which approximately double for every 10˚C increase in the junction temperature, Tj. Due to the limitedproduction test time, the input bias currents measured are correlated to junction temperature. In normal operation the junction temperature rises above the ambienttemperature as a result of internal power dissipation, PD. Tj = TA + θjA PD where θjA is the thermal resistance from junction to ambient. Use of a heat sink is recom-mended if input bias current is to be kept to a minimum.

Note 7: Supply voltage rejection ratio is measured for both supply magnitudes increasing or decreasing simultaneously in accordance with common practice.VS = ±6V to ±15V.

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Typical Performance Characteristics

Input Bias Current

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Input Bias Current

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Supply Current

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Positive Common-Mode InputVoltage Limit

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Negative Common-Mode InputVoltage Limit

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Positive Current Limit

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Negative Current Limit

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Voltage Swing

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Output Voltage Swing

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Typical Performance Characteristics (Continued)

Gain Bandwidth

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Bode Plot

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Slew Rate

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Distortion vs Frequency

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Undistorted OutputVoltage Swing

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Open Loop FrequencyResponse

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Common-Mode RejectionRatio

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Power Supply RejectionRatio

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Equivalent Input NoiseVoltage

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Typical Performance Characteristics (Continued)

Pulse Response

Open Loop VoltageGain (V/V)

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Output Impedance

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Inverter Setting Time

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Small Signal Inverting

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Small Signal Non-Inverting

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Large Signal Inverting

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Large Signal Non-Inverting

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Pulse Response (Continued)

Application HintsThese devices are op amps with an internally trimmed inputoffset voltage and JFET input devices (BI-FET II). TheseJFETs have large reverse breakdown voltages from gate tosource and drain eliminating the need for clamps across theinputs. Therefore, large differential input voltages can easilybe accommodated without a large increase in input current.The maximum differential input voltage is independent of thesupply voltages. However, neither of the input voltagesshould be allowed to exceed the negative supply as this willcause large currents to flow which can result in a destroyedunit.

Exceeding the negative common-mode limit on either inputwill cause a reversal of the phase to the output and force theamplifier output to the corresponding high or low state. Ex-ceeding the negative common-mode limit on both inputs willforce the amplifier output to a high state. In neither casedoes a latch occur since raising the input back within thecommon-mode range again puts the input stage and thusthe amplifier in a normal operating mode.

Exceeding the positive common-mode limit on a single inputwill not change the phase of the output; however, if both in-puts exceed the limit, the output of the amplifier will be forcedto 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 within3V of the negative supply, an increase in input offset voltagemay occur.

Each amplifier is individually biased by a zener referencewhich allows normal circuit operation on ±6V power sup-plies. Supply voltages less than these may result in lowergain bandwidth and slew rate.

The amplifiers will drive a 2 kΩ load resistance to ±10V overthe full temperature range of 0˚C to +70˚C. If the amplifier isforced to drive heavier load currents, however, an increasein input offset voltage may occur on the negative voltageswing and finally reach an active current limit on both posi-tive and negative swings.

Precautions should be taken to ensure that the power supplyfor the integrated circuit never becomes reversed in polarityor that the unit is not inadvertently installed backwards in asocket as an unlimited current surge through the resultingforward diode within the IC could cause fusing of the internalconductors and result in a destroyed unit.

Because these amplifiers are JFET rather than MOSFET in-put op amps they do not require special handling.

As with most amplifiers, care should be taken with leaddress, component placement and supply decoupling in orderto ensure stability. For example, resistors from the output toan input should be placed with the body close to the input tominimize “pick-up” and maximize the frequency of the feed-back pole by minimizing the capacitance from the input toground.

A feedback pole is created when the feedback around anyamplifier is resistive. The parallel resistance and capacitancefrom the input of the device (usually the inverting input) to ACground set the frequency of the pole. In many instances thefrequency of this pole is much greater than the expected 3dB frequency of the closed loop gain and consequently thereis negligible effect on stability margin. However, if the feed-back pole is less than approximately 6 times the expected 3dB 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 equalto the original feedback pole time constant.

Current Limit (R L = 100Ω)

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Detailed Schematic

Typical Applications

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Three-Band Active Tone Control

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Typical Applications (Continued)

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• All potentiometers are linear taper• Use the LF347 Quad for stereo applications

Note 8: All controls flat.

Note 9: Bass and treble boost, mid flat.

Note 10: Bass and treble cut, mid flat.

Note 11: Mid boost, bass and treble flat.

Note 12: Mid cut, bass and treble flat.

Improved CMRR Instrumentation Amplifier

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C and E are separate isolated groundsMatching of R2’s, R4’s and R5’s control CMRRWith AVT = 1400, resistor matching = 0.01%: CMRR = 136 dB• Very high input impedance• Super high CMRR

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Typical Applications (Continued)

Fourth Order Low Pass Butterworth Filter

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Fourth Order High Pass Butterworth Filter

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Typical Applications (Continued)

Ohms to Volts Converter

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Physical Dimensions inches (millimeters) unless otherwise noted

Order Number TL082CMNS Package M08A

Order Number TL082CPNS Package N08E

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Notes

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NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORTDEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONALSEMICONDUCTOR CORPORATION. As used herein:

1. Life support devices or systems are devices orsystems which, (a) are intended for surgical implantinto the body, or (b) support or sustain life, andwhose failure to perform when properly used inaccordance with instructions for use provided in thelabeling, can be reasonably expected to result in asignificant injury to the user.

2. A critical component is any component of a lifesupport device or system whose failure to performcan be reasonably expected to cause the failure ofthe life support device or system, or to affect itssafety or effectiveness.

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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.