FET-Input, Low Distortion Operational Amplifier …

1 FEATURES LOW Distortion : at 1kHz LOW NOISE: 10nV/ Hz HIGH SLEW RATE: 25V/ s WIDE GAIN-BANDWIDTH: 20 MHz UNITY-GAIN STABLE WIDE SUPPLY RANGE: VS = to 24V DRIVES 600 LOAD DUAL VERSION AVAILABLE (OPA2604)FET-Input, Low DistortionOPERATIONAL AMPLIFIERAPPLICATIONS PROFESSIONAL AUDIO EQUIPMENT PCM DAC I/V CONVERTERS SPECTRAL ANALYSIS EQUIPMENT ACTIVE FILTERS TRANSDUCER AMPLIFIERS DATA ACQUISITIONOPA604 DESCRIPTIONThe OPA604 is a FET-input Operational Amplifier designedfor enhanced AC performance. Very low Distortion , low noiseand wide bandwidth provide superior performance in highquality audio and other applications requiring excellent dy-namic circuit techniques and special laser trimming of dynamiccircuit performance yield very low harmonic Distortion . Theresult is an op amp with exceptional sound quality.

2 The low-noise FET input of the OPA604 provides wide dynamicrange, even with high source impedance. Offset voltage islaser-trimmed to minimize the need for interstage OPA604 is available in 8-pin plastic mini-DIP and SO-8surface-mount packages, specified for the 25 C to +85 Ctemperature (1)(3)(+)(2)( )(7)V+(6)VO(4)V OutputStage(1)NOTE: (1) Patents Granted: #5053718, 5019789 (5)(1)OPA604 OPA604 SBOS019A JANUARY 1992 SEPTEMBER DATA information is current as of publication conform to specifications per the terms of Texas Instrumentsstandard warranty. Production processing does not necessarily includetesting of all 1992-2003, Texas Instruments IncorporatedPlease be aware that an important notice concerning availability, standard warranty, and use in critical applications ofTexas Instruments semiconductor products and disclaimers thereto appears at the end of this data trademarks are the property of their respective MAXIMUM RATINGSP ower Supply Voltage.

3 25 VInput Voltage .. (V ) 1V to (V+)+1 VOutput Short Circuit to Ground .. ContinuousOperating Temperature .. 40 C to +100 CStorage Temperature .. 40 C to +125 CJunction Temperature .. +150 CLead Temperature (soldering, 10s) AP .. +300 CLead Temperature (soldering, 3s) AU .. +260 CPIN CONFIGURATIONTop ViewDIP, SOIC1234 Offset Trim In+In VS8765No Internal Connection+VSOutputOffset TrimELECTROSTATICDISCHARGE SENSITIVITYAny integrated circuit can be damaged by ESD. Texas Instru-ments recommends that all integrated circuits be handled withappropriate precautions. Failure to observe proper handlingand installation procedures can cause damage can range from subtle performance degradationto complete device failure. Precision integrated circuits may bemore susceptible to damage because very small parametricchanges could cause the device not to meet published INFORMATIONFor the most current package and ordering information, seeto the Package Option Addendum at the end of this CHARACTERISTICSTA = +25 C, VS = 15V, unless otherwise , AUPARAMETERCONDITIONMINTYPMAXUNITSOFFSET VOLTAGEI nput Offset Voltage 1 5mVAverage Drift 8 V/ CPower Supply RejectionVS = 5 to 24V80100dBINPUT BIAS CURRENT(1)Input Bias CurrentVCM = 0V50pAInput Offset CurrentVCM = 0V 3pANOISEI nput Voltage NoiseNoise Density.

4 F = 10Hz25nV/ Hzf = 100Hz15nV/ Hzf = 1kHz11nV/ Hzf = 10kHz10nV/ HzVoltage Noise, BW = 20Hz to VPPI nput Bias Current NoiseCurrent Noise Density, f = to 20kHz4fA/ HzINPUT VOLTAGE RANGEC ommon-Mode Input Range 12 13 VCommon-Mode RejectionVCM = 12V80100dBINPUT IMPEDANCED ifferential1012 || 8 || pFCommon-Mode1012 || 10 || pFOPEN-LOOP GAINOpen-Loop Voltage GainVO = 10V, RL = 1k 80100dBFREQUENCY RESPONSEGain-Bandwidth ProductG = 10020 MHzSlew Rate20 VPP, RL = 1k 1525V/ sSettling Time: = 1, 10V sTotal Harmonic Distortion + Noise (THD+N)G = 1, f = = , RL = 1k OUTPUTV oltage OutputRL = 600 11 12 VCurrent OutputVO = 12V 35mAShort Circuit Current 40mAOutput Resistance, Open-Loop25 POWER SUPPLYS pecified Operating Voltage 15 VOperating Voltage Range 24 VCurrent 7mATEMPERATURE RANGES pecification 25+85 CStorage 40+125 CThermal Resistance(2), JA90 C/WNOTES: (1) Typical performance, measured fully warmed-up.

5 (2) Soldered to circuit board see CHARACTERISTICSTA = +25 C, VS = 15V, unless otherwise HARMONIC Distortion + NOISEvs FREQUENCYF requency (Hz)THD + N (%) 20kG = 100V/VG = 10V/VG = 1V/VMeasurement BW = 80kHzSee Distortion Measure-ments for description oftest V = HARMONIC Distortion + NOISEvs OUTPUT VOLTAGEO utput Voltage (VPP)THD + N (%) V Of = 1kHzMeasurement BW = 80kHzSee Distortion Measurements for description of test GAIN/PHASE vs FREQUENCYF requency (Hz)Voltage Gain (dB)120100806040200 201101001k10k100k1M10M0 45 90 135 180 Phase Shift (Degrees)G INPUT VOLTAGE AND CURRENT NOISESPECTRAL DENSITY vs FREQUENCYF requency (Hz)Voltage Noise (nV/ Hz)11k100101101001k10k100k1 MCurrent Noise (fA/ Hz)1k100101 Voltage NoiseCurrent NoiseINPUT BIAS AND INPUT OFFSET CURRENT vs TEMPERATUREA mbient Temperature ( C)Input Bias Current (pA) 75100nA10nA1nA100101 Input Offset Current (pA) 50 250255075100125 InputOffset CurrentInputBias CurrentINPUT BIAS AND INPUT OFFSET CURRENT vs INPUT COMMON-MODE VOLTAGEC ommon-Mode Voltage (V)Input Bias Current (pA) 1510nA1nA10010 Input Offset Current (pA)1nA100101 10 50 51015 InputOffset CurrentInputBias CHARACTERISTICS (Cont.)

6 TA = +25 C, VS = 15V, unless otherwise REJECTION vs COMMON-MODE VOLTAGEC ommon-Mode Voltage (V)Common-Mode Rejection (dB) 151201101009080 10 50 51015 POWER SUPPLY AND COMMON-MODEREJECTION vs FREQUENCYF requency (Hz)Power Supply Rejection (dB)101201008060402001001k10k100k1M10 MCommon-Mode Rejection (dB)120100806040200+PSR PSRCMRAOL, PSR, AND CMR vs SUPPLY VOLTAGES upply Voltage ( VS)AOL, PSR, CMR (dB)512011010090807010152025 CMRAOLPSRGAIN-BANDWIDTH AND SLEW RATEvs TEMPERATURET emperature ( C)Gain-Bandwidth (MHz) 752824201612 252575125 Slew Rate (V/ s)3025201510 50050100 Slew RateGain-BandwidthG = +100 INPUT BIAS CURRENT vs TIME FROM POWER TURN-ONTime After Power Turn-On (min)Input Bias Current (pA)01nA10010112345VS = 24 VVS = 15 VVS = 5 VGAIN-BANDWIDTH AND SLEW RATEvs SUPPLY VOLTAGES upply Voltage ( VS)Gain-Bandwidth (MHz)5282420161210152025 Slew RateGain-BandwidthG = +100 Slew Rate (V/ s) CHARACTERISTICS (Cont.)

7 TA = +25 C, VS = 15V, unless otherwise TIME vs CLOSED-LOOP GAINC losed-Loop Gain (V/V)Settling Time ( s) 1543210 10 100 = 10V StepRL = 1k CL = 50pFMAXIMUM OUTPUT VOLTAGE SWING vs FREQUENCYF requency (Hz)Output Voltage (Vp-p)10k3020100100k1M10MV = 15 VSSUPPLY CURRENT vs TEMPERATUREA mbient Temperature ( C)Supply Current (mA) 7576543 50 250255075100125VS = 24 VVS = 15 VVS = 5 VSHORT-CIRCUIT CURRENT vs TEMPERATUREA mbient Temperature ( C)Short-Circuit Current (mA) 756050403020 50 250255075100125 ISC+ and ISC 100+10021 Output Voltage (V)SMALL-SIGNAL TRANSIENT RESPONSE0 10+10105 Output Voltage (V)LARGE-SIGNAL TRANSIENT CHARACTERISTICS (Cont.)TA = +25 C, VS = 15V, unless otherwise INFORMATIONOFFSET VOLTAGE ADJUSTMENTThe OPA604 offset voltage is laser-trimmed and will requireno further trim for most applications.

8 As with most amplifiers,externally trimming the remaining offset can change driftperformance by about V/ C for each 100 V of adjustedoffset. The OPA604 can replace many other amplifiers byleaving the external null circuit OPA604 is unity-gain stable, making it easy to use in awide range of circuitry. Applications with noisy or high imped-ance power supply lines may require decoupling capacitorsclose to the device pins. In most cases, a 1 F tantalumcapacitor at each power supply pin is MEASUREMENTSThe Distortion produced by the OPA604 is below the mea-surement limit of virtually all commercially available equip-ment. A special test circuit, however, can be used to extendthe measurement amp Distortion can be considered an internal error sourcewhich can be referred to the input.

9 Figure 2 shows a circuitwhich causes the op amp Distortion to be 101 times greaterthan normally produced by the op amp. The addition of R3 tothe otherwise standard noninverting Amplifier configurationalters the feedback factor or noise gain of the circuit. Theclosed-loop gain is unchanged, but the feedback availablefor error correction is reduced by a factor of 101. Thisextends the measurement limit, including the effects of thesignal-source purity, by a factor of 101. Note that the inputsignal and load applied to the op amp are the same as withconventional feedback without of this technique can be verified by duplicatingmeasurements at high gain and/or high frequency where thedistortion is within the measurement capability of the testequipment.

10 Measurements for this data sheet were madewith the Audio Precision System One, which greatly simpli-fies such repetitive measurements. The measurement tech-nique can, however, be performed with manual distortionmeasurement LOADSThe dynamic characteristics of the OPA604 have beenoptimized for commonly encountered gains, loads and oper-ating conditions. The combination of low closed-loop gainand capacitive load will decrease the phase margin and maylead to gain peaking or oscillations. Load capacitance reactswith the op amp s open-loop output resistance to form anadditional pole in the feedback loop. Figure 3 shows variouscircuits which preserve phase margin with capacitive details of analysis techniques and applications circuits,refer to application bulletin AB-028 (SBOA015) located 1.