LT1115CN8

LT1115 Ultralow Noise, Low Distortion, Audio Op Amp FEATURES ■ ■ ■ ■ ■ ■ DESCRIPTIO ■ Voltage Noise: 1.2nV/√Hz Max at 1kHz 0.9nV/√Hz Typ at 1kHz Voltage and Current Noise 100% Tested Gain-Bandwidth Product: 40MHz Min Slew Rate: 10V/µs Min Voltage Gain: 2 Million Min Low THD at 10kHz, AV = –10, RL = 600Ω: 0.002% VO = 7VRMS Low IMD, CCIF Method, AV = +10: 0.002% RL = 600Ω VO = 7VRMS The LT ®1115 is the lowest noise audio operational amplifier available. This ultralow noise performance (0.9nV/√Hz at 1kHz) is combined with high slew rates (>15V/µs) and very low distortion specifications. The RIAA circuit shown below using the LT1115 has very low distortion and little deviation from ideal RIAA response (see graph). , LTC and LT are registered trademarks of Linear Technology Corporation. APPLICATIO S ■ ■ ■ ■ ■ ■ ■ High Quality Audio Preamplifiers Low Noise Microphone Preamplifiers Very Low Noise Instrumentation Amplifiers Low Noise Frequency Synthesizers Infrared Detector Amplifiers Hydrophone Amplifiers Low Distortion Oscillators TYPICAL APPLICATIO 18V RIAA Phonograph Preamplifier (40/60db Gain) 18V + INPUT RIN 47.5k (MM) 100Ω (MC) COM CIN (SELECT PER PHOTO CARTRIDGE) 3 + – 7 6 1µF 35V 1µF 35V + 2 1 A2 LT1010CT 3 RBOOST 49.9Ω 4 5 562Ω OUTPUT 3900pF 2 A1 LT1115 4 100Ω 2N4304* ~250Ω SELECT FOR 2mA 2mA 1µF 35V RL 25k V+ 18V 499Ω 22.6Ω 17.8k 330pF + COM 470µF 35V + V– 470µF 35V –18V 210Ω SINGLE POINT BOARD GROUND OPEN—MM CLOSED—MC 82.5k 4.7µF FILM 3900pF + 2200µF 16V NOTE: BYPASS SUPPLIES WITH LOW ESR CAPS OTHER CAPS: HIGH QUALITY FILM + + –18V 1µF 35V DEVIATION (dB) –18V 210k 15nF RESISTORS 1% *OR USE 2mA CURRENT SOURCE MM = MOVING MAGNET MC = MOVING COIL LT1115 • TA01 U Measured Deviation from RIAA Response. lnput at 1kHz = 1mVRMS Pre-Emphasized 1.0000 0.80000 0.60000 0.40000 0.20000 0.0 –0.2000 –0.4000 –0.6000 –0.8000 –1.000 20 100 1k FREQUENCY (Hz) 10k 50k LT1115 • TA02 U U VS = ± 18V RS = 25Ω TA = 25°C MEASURED COMPUTER SIMULATED 1115fa 1 LT1115 ABSOLUTE (Note 1) AXI U RATI GS Operating Temperature Range ..................... 0°C to 70°C Storage Temperature Range ..................–65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C Supply Voltage ...................................................... ±22V Differential Input Current (Note 5) ...................... ±25mA Input Voltage ............................ Equal to Supply Voltage Output Short-Circuit Duration .......................... Indefinite PACKAGE DESCRIPTIO TOP VIEW VOS TRIM 1 –IN 2 +IN 3 V– 4 VOS TRIM 7 V+ 8 – + 6 OUT OVER5 COMP ORDER PART NUMBER LT1115CN8 N PACKAGE 8-LEAD PDIP TJMAX = 115°C, θJA = 130°C/W Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS SYMBOL THD IMD VOS IOS IB en PARAMETER Total Harmonic Distortion at 10kHz Inter-Modulation Distortion (CCIF) Input Offset Voltage Input Offset Current Input Bias Current Input Noise Voltage Density Wideband Noise Corresponding Voltage Level re 0.775V in Input Noise Current Density (Note 3) Input Resistance Common Mode Differential Mode Input Capacitance Input Voltage Range CONDITIONS Av = –10, VO = 7VRMS, RL = 600 Av = 10, VO = 7VRMS, RL = 600 (Note 2) VCM = 0V VCM = 0V fo = 10Hz fo = 1000Hz, 100% tested DC to 20kHz fo = 10Hz fo = 1000Hz, 100% tested 2 U U WW W TOP VIEW NC 1 NC 2 TRIM 3 –IN 4 +IN 5 V– 6 – + 16 NC 15 NC 14 TRIM 13 V + 12 OUTPUT 11 OVERCOMP 10 NC 9 NC ORDER PART NUMBER LT1115CSW NC 7 NC 8 SW PACKAGE 16-LEAD PLASTIC SO TMAX = 115°C, θJA = 130°C/W LT1115 • POI01 VS = ±18V, TA = 25°C, unless otherwise noted. MIN TYP < 0.002 < 0.0002 50 30 ±50 1.0 0.9 120 – 136 4.7 1.2 250 15 5 ±13.5 ±15.0 200 200 ±380 1.2 MAX UNITS % % µV nA nA nV/√Hz nV/√Hz nVRMS dB pA/√Hz pA/√Hz MΩ kΩ pF V 2.2 1115fa LT1115 ELECTRICAL CHARACTERISTICS SYMBOL CMRR PSRR AVOL PARAMETER Common Mode Rejection Ratio Power Supply Rejection Ratio Large-Signal Voltage Gain VS = ±18V, TA = 25°C, unless otherwise noted. MIN 104 104 2.0 1.5 1.0 ±15.5 ±14.5 ±11.0 10 40 TYP 123 126 20 15 10 ±16.5 ±15.5 ±14.5 15 70 70 8.5 11.5 MAX UNITS dB dB V/µV V/µV V/µV V V V V/µs MHz Ω mA CONDITIONS VCM = ±13.5V VS = ±4V to ±19V RL ≥ 2kΩ, Vo = ±14.5V RL ≥ 1kΩ, Vo = ±13V RL ≥ 600Ω, Vo = ±10V No Load RL ≥ 2kΩ RL ≥ 600Ω AVCL = –1 fo = 20kHz (Note 4) Vo = 0, Io = 0 VOUT Maximum Output Voltage Swing Slew Rate Gain-Bandwidth Product Open Loop 0utput Impedance Supply Current SR GBW Zo IS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ±18V, unless otherwise noted. SYMBOL VOS ∆VOS/∆T IOS IB CMRR PSRR AVOL VOUT PARAMETER Input Offset Voltage Average Input Offset Drift Input Offset Current Input Bias Current Input Voltage Range Common Mode Rejection Ratio Power Supply Rejection Ratio Large-Signal Voltage Gain Maximum Output Voltage Swing Supply Current VCM = ±13V VS = ±4.5V to ±18V RL ≥ 2kΩ, Vo = ±13V RL ≥ 1kΩ, Vo = ±11V No Load RL ≥ 2kΩ RL ≥ 600Ω VCM = 0V VCM = 0V ● ● ● ● ● ● CONDITIONS (Note 2) ● MIN TYP 75 0.5 40 ±70 MAX 280 300 ±550 UNITS µV µV/°C nA nA V dB dB V/µV V/µV V V V ±13 100 100 1.5 1.0 ±15 ±13.8 ±10 ±14.8 120 123 15 10 ±16.3 ±15.3 ±14.3 9.3 13 ● ● IS mA Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Input Offset Voltage measurements are performed by automatic test equipment approximately 0.5 sec after application of power. Note 3: Current noise is defined and measured with balanced source resistors. The resultant voltage noise (after subtracting the resistor noise on an RMS basis) is divided by the sum of the two source resistors to obtain current noise. Note 4: Gain-bandwidth product is not tested. It is guaranteed by design and by inference from the slew rate measurement. Note 5: The inputs are protected by back-to-back diodes. Current limiting resistors are not used in order to achieve low noise. If differential input voltage exceeds ±1.8V, the input current should be limited to 25mA. 1115fa 3 LT1115 TYPICAL PERFOR A CE CHARACTERISTICS Wideband Noise, DC to 20kHz 10 VS = ± 18V TA = 25°C TOTAL NOISE DENSITY (nV/√Hz) RMS VOLTAGE NOISE (µV) 0.5µV/DIV FPO 0.5ms/DIV 0.01 100 1k 100k 10k BANDWIDTH (Hz) 1M 10M 0.1 1 THD + Noise vs Frequency (AV = –10) TOTAL HARMONIC DISTORTION + NOISE (%) TOTAL HARMONIC DISTORTION + NOISE (%) TOTAL HARMONIC DISTORTION + NOISE (%) 0.010 AV = – 10 RL = 600 VIN = 2VP-P (700mVRMS) VOUT = 20VP-P (7VRMS) TA = 25°C VS = ± 18V 0.001 0.0005 20 100 1k FREQUENCY (Hz) 20k LT1115 • TPC04 THD + Noise vs Frequency (AV = 10) TOTAL HARMONIC DISTORTION + NOISE (%) TOTAL HARMONIC DISTORTION + NOISE (%) AV = 10 RL = 600 VIN = 2VP-P (700mVRMS) VOUT = 20VP-P (7VRMS) TA = 25°C VS = ± 18V AV = 100 VIN = 200mVP-P (700VRMS) VOUT = 20mVP-P (7VRMS) TA = 25°C RL = 600 VS = ±18V 0.010 TOTAL HARMONIC DISTORTION + NOISE (%) 0.010 0.001 0.0005 20 100 1k FREQUENCY (Hz) 20k LT1115 • TPC07 4 UW Wideband Voltage Noise (0.1Hz to Frequency Indicated) 100 Total Noise vs Matched Source Resistance RS – RS + 1 10 AT 10Hz 1.0 AT 1kHz 2 RS NOISE ONLY 0.1 VS = ± 18V TA = 25°C 3 10 30 100 300 1k 3k 10k MATCHED SOURCE RESISTANCE, RS (Ω) LT1115 • TPC03 LT1115 • TPC02 THD + Noise vs Frequency (AV = –100) 0.1 AV = –100 RL = 600 VIN = 200mVP-P (70mVRMS) VOUT = 20VP-P (7VRMS) TA = 25°C VS = ± 18V 0.010 0.1 THD + Noise vs Frequency (AV = –1000) AV = – 1000 RL = 600 VIN = 20mVP-P (7mVRMS) VOUT = 20VP-P (7VRMS) TA = 25°C VS = ± 18V 0.010 0.001 20 0.001 100 1k FREQUENCY (Hz) 20k LT1115 • TPC05 20 100 1k FREQUENCY (Hz) 20k LT1115 • TPC06 THD + Noise vs Frequency (AV = 100) 0.1 0.1 THD + Noise vs Frequency (AV = 1000) AV = 1000 VIN = 20mVP-P (7mVRMS) VOUT = 20VP-P (7VRMS) TA = 25°C RL = 600 VS = ±18V 0.010 0.001 0.0005 20 100 1k FREQUENCY (Hz) 20k LT1115 • TPC08 0.001 20 100 1k FREQUENCY (Hz) 20k LT1115 • TPC09 1115fa LT1115 TYPICAL PERFOR A CE CHARACTERISTICS CCIF IMD Test (Twin Equal Amplitude Tones at 13 and 14kHz)* INTERMODULATION DISTORTION (at 1kHz) (%) INTERMODULATION DISTORTION (at 1kHz) (%) 0.1 AV = 10 RL = 600 TA = 25°C VS = ± 18V 0.010 SLEW RATE (V/µs) 0.001 0.0001 10m 0.1 1 OUTPUT AMPLITUDE (VRMS) Total Noise vs Unmatched Source Resistance 100 RS CURRENT NOISE DENSITY (pA/√Hz) TOTAL NOISE DENSITY (nV/√Hz) 100 RMS VOLTAGE NOISE DENSITY (nV/√Hz) 10 AT 10Hz 1.0 AT 1kHz RS NOISE ONLY VS = ± 18V TA = 25°C 0.1 1 3 10 30 100 300 1k 3k 10k UNMATCHED SOURCE RESISTANCE, RS (Ω) LT1115 • TPC13 Voltage Noise vs Supply Voltage 1.5 10 RMS VOLTAGE NOISE DENSITY (nV/√Hz) TA = 25°C 1.25 SUPPLY CURRENT (mA) 8 7 6 5 4 3 2 1 VS = ± 15V VS = ± 5V SHORT-CIRCUIT CURRENT (mA) SINKING SOURCING 1.0 AT 1kHz 0.75 0.5 0 ±5 ± 10 ± 15 SUPPLY VOLTAGE (V) ±20 LT1115 • TPC16 *See CCIF Test Note at end of “Typical Performance Characteristics”. 1115fa UW 10 LT1115 • TPC10 CCIF IMD Test (Twin Equal Amplitude Tones at 13 and 14kHz)* 0.1 AV = 10 RL = 10k TA = 25°C VS = ±18V 0.010 Slew Rate, Gain-Bandwidth-Product vs Overcompensation Capacitor 100 10000 10 GWB 1000 GAIN AT 20kHz SLEW 1 COC FROM PIN 5 TO PIN 6 VS = ±18V TA = 25°C 1 100 0.001 0.0001 10m 0.1 1 0.1 OUTPUT AMPLITUDE (VRMS) 10 10 10000 1000 10 100 OVERCOMPENSATION CAPACITOR (pF) LT1115 • TPC12 LT1115 • TPC11 Current Noise Spectrum 2.0 Voltage Noise vs Temperature VS = ±18V 1.6 10 1.2 AT 10Hz AT 1kHz TYPICAL 1 1/f CORNER = 250Hz 0.8 0.4 0.1 10 0 1k 100 FREQUENCY (Hz) 10k LT1115 • TPC14 0 15 30 45 TEMPERATURE (°C) 60 75 LT1115 • TPC15 Supply Current vs Temperature 50 VS = ± 18V 9 Output Short-Circuit Current vs Time 40 30 20 10 0 – 10 – 20 – 30 – 40 25°C VS = ± 18V 25°C 0 0 15 30 45 TEMPERATURE (°C) 60 75 LT1115 • TPC17 – 50 2 3 0 1 TIME FROM OUTPUT SHORT TO GROUND (MINUTES) LT1115 • TPC18 5 LT1115 TYPICAL PERFOR A CE CHARACTERISTICS Voltage Gain vs Frequency 160 140 120 70 60 VOLTAGE GAIN (dB) 100 80 60 40 20 0 VS = ± 18V TA = 25°C RL = 2k 10 100 1k 10k 100k 1M 10M 100M FREQUENCY (Hz) LT1115 • TPC19 VOLTAGE GAIN (V/µV) VOLTAGE GAIN (dB) –20 0.01 0.1 1 Voltage Gain vs Load Resistance 100 80 COMMON MODE LIMIT (V) REFERRED TO POWER SUPPLY VS = ±18V TA = 25°C ILMAX = 27mA AT 25°C OVERSHOOT (% ) VOLTAGE GAIN (V/µV) 10 1 0.1 1 LOAD RESISTANCE (kΩ) Common Mode Rejection Ratio vs Frequency 140 COMMON MODE REJECTION RATIO (dB) POWER SUPPLY REJECTION RATIO (dB) 120 100 80 60 40 20 0 10 VS = ± 18V TA = 25°C 100 10k 1k 100k FREQUENCY (Hz) 1M 10M 100 80 60 40 20 VS = ± 18V TA = 25°C 1 10 POSITIVE SUPPLY NEGATIVE SUPPLY 5V/DIVISION 6 UW Gain, Phase vs Frequency 70 Voltage Gain vs Supply Voltage 100 TA = 25°C 60 50 40 30 PHASE 50 40 30 RL = 2kΩ RL = 600Ω PHASE MARGIN (DEGREES) 10 GAIN 20 10 0 20 10 – 10 10k VS = ± 18V TA = 25°C CL = 10pF 100k 1M 10M FREQUENCY (Hz) 0 – 10 100M LT1115 • TPC20 1 0 ± 10 ± 15 ±5 SUPPLY VOLTAGE (V) ± 20 LT1115 • TPC21 Capacitance Load Handling V+ –1 30pF Common Mode Limit Over Temperature 70 60 50 40 30 20 10 0 RS + – 2k CL –2 –3 –4 VS = ± 5V VS = ± 18V AV = – 1, RS = 2k AV = – 10 RS = 200Ω AV = – 100 RS = 20Ω VS = ± 18V TA = 25°C 10000 LT1115 • TPC23 +4 +3 +2 +1 V– 0 15 30 45 TEMPERATURE (°C) 60 75 VS = ± 5V TO ±18V 10 LT1115 • TPC22 10 100 1000 CAPACITIVE LOAD, CL (pF) LT1115 • TPC24 Power Supply Rejection Ratio vs Frequency 160 140 120 Large-Signal Transient Response FPO 1µs/DIVISION AV = –1 RS = Rf = 2k Cf = 30pF 0 0.1 LT1115 • TPC25 100 1k 10k 100k 1M 10M FREQUENCY (Hz) LT1115 • TPC26 1115fa LT1115 TYPICAL PERFOR A CE CHARACTERISTICS Small-Signal Transient Response 30 PEAK-TO-PEAK OUTPUT VOLTAGE (V) 20 15 10 *POWER BANDWIDTH SLEW RATE fP = πEOP 5 f = POWER BANDWIDTH P EP-P = PEAK-TO-PEAK AMPLIFIER 0 10k OUTPUT VOLTAGE OUTPUT IMPEDANCE (Ω) 20mV/DIVISION 0.2µs/DIVISION AV = –1, RS = Rf = 2kΩ Cf = 30pF CL = 80pF FPO APPLICATIO S I FOR ATIO The LT1115 is a very high performance op amp, but not necessarily one which is optimized for universal application. Because of very low voltage noise and the resulting high gain-bandwidth product, the device is most applicable to relatively high gain applications. Thus, while the LT1115 will provide notably superior performance to the 5534 in most applications, the device may require circuit modifications to be used at very low noise gains. The part is not generally applicable for unity gain followers or inverters. In general, it should always be used with good low impedance bypass capacitors on the supplies, low impedance feedback values, and minimal capacitive loading. Ground plane construction is recommended, as is a compact layout. U W UW FPO Maximum Output vs Frequency (Power Bandwidth*) VS = ± 18V TA = 25°C RL = 2kΩ 100 Closed-Loop Output Impedance IO = 1mA VS = ±18V TA = 25°C 25 10 1 AV = 1000 0.1 AV = 5 0.01 1M 100k FREQUENCY (Hz) 10M LT1115 • TPC29 0.001 10 100 10k 1k FREQUENCY (Hz) 100k 1M LT1115 • TPC30 CCIF Testing Note: The CCIF twin-tone intermodulation test inputs two closely spaced equal amplitude tones to the device under test (DUT). The analyzer then measures the intermodulation distortion (IMD) produced in the DUT by measuring the difference tone equal to the spacing between the tones. The amplitude of the lMD test input is in sinewave peak equivalent terms. As an example, selecting an amplitude of 1.000V will result in the complex IMD signal having the same 2.828V peak-to-peak amplitude that a 1.000V sinewave has. Clipping in a DUT will thus occur at the same input amplitude for THD + N and IMD modes. UU Voltage Noise vs Current Noise The LT1115’s less than 1nV/√Hz voltage noise matches that of the LT1028 and is three times better than the lowest voltage noise heretofore available (on the LT1007/1037). A necessary condition for such low voltage noise is operating the input transistors at nearly 1mA of collector currents, because voltage noise is inversely proportional to the square root of the collector current. Current noise, however, is directly proportional to the square root of the collector current. Consequently, the LT1115’s current noise is significantly higher than on most monolithic op amps. 1115fa 7 LT1115 APPLICATIO S I FOR ATIO Therefore, to realize truly low noise performance it is important to understand the interaction between voltage noise (en), current noise (in) and resistor noise (rn). Total Noise vs Source Resistance The total input referred noise of an op amp is given by et = [en2 + rn2 + (inReq)2]1/2 where Req is the total equivalent source resistance at the two inputs and rn = √4kTReq = 0.13√Req in nV/√Hz at 25°C As a numerical example, consider the total noise at 1kHz of the gain of 1000 amplifier shown below. 100Ω 100k – LT1115 100Ω + LT1115 • AI01 Req = 100Ω + 100Ω||100k ≈ 200Ω rn = 0.13√200 = 1.84nV/√Hz en = 0.85nV/√Hz in = 1.0pA/√Hz et = [0.852 + 1.842 + (1.0 x 2.0)2]1/2 = 2.04nV/√Hz output noise = 1000 et = 2.04µV/√Hz At very low source resistance (Req < 40Ω) voltage noise dominates. As Req is increased resistor noise becomes the largest term—as in the example above—and the LT1115’s voltage noise becomes negligible. As Req is further increased, current noise becomes important. At 1kHz, when Req is in excess of 20kΩ, the current noise component is larger than the resistor noise. The Total Noise vs Matched Source Resistance plot in the Typical Performance Characteristics section, illustrates the above calculations. 8 U The plot also shows that current noise is more dominant at low frequencies, such as 10Hz. This is because resistor noise is flat with frequency, while the 1/f corner of current noise is typically at 250Hz. At 10Hz when Req > 1kΩ, the current noise term will exceed the resistor noise. When the source resistance is unmatched, the Total Noise vs Unmatched Source Resistance plot should be consulted. Note that total noise is lower at source resistances below 1kΩ because the resistor noise contribution is less. When Rs > 1kΩ total noise is not improved, however. This is because bias current cancellation is used to reduce input bias current. The cancellation circuitry injects two correlated current noise components into the two inputs. With matched source resistors the injected current noise creates a common-mode voltage noise and gets rejected by the amplifier. With source resistance in one input only, the cancellation noise is added to the amplifier’s inherent noise. In summary, the LT1115 is the optimum amplifier for noise performance—provided that the source resistance is kept low. The following table depicts which op amp manufactured by Linear Technology should be used to minimize noise—as the source resistance is increased beyond the LT1115’s level of usefulness. Best Op Amp for Lowest Total Noise vs Source Resistance SOURCE RESISTANCE (NOTE 1) 0 to 400Ω 400Ω to 4kΩ 4kΩ to 40kΩ 40kΩ to 500kΩ 500kΩ to 5MΩ > 5M BEST OP AMP AT LOW FREQ (10Hz) WIDEBAND (1kHz) LT1028/1115 LT1007/1037 LT1001* LT1012* LT1012* or LT1055 LT1055 LT1028/1115 LT1028/1115 LT1007/1037 LT1001* LT1012* LT1055 Note 1: Source resistance is defined as matched or unmatched, e.g., RS = 1kΩ means: 1kΩ at each input, or 1kΩ at one input and zero at the other. *These op amps are best utilized in applications requiring less bandwidth than audio. 1115fa W UU LT1115 TYPICAL APPLICATIO S R1 1k, 0.1% 18V R3 316k, 0.1% INPUT RP 30k 1% R2 1k, 0.1% R4 316k, 0.1% Figure 1. Balanced Transformerless Microphone Preamp THD + Noise vs Frequency (Figure 1) TOTAL HARMONIC DISTORTION + NOISE (%) 1 TA = 25°C RL = 100kΩ VIN = 10mVRMS VOUT = 2.92VRMS RS = 150Ω 0.1 0.010 20 100 1k FREQUENCY (Hz) 20k LT1115 • TA04 + U + 2 – + 7 6 1µF 35V LOW ESR 4.7µF FILM 100 1% OUT LT1115 3 4 –18V 1µF 35V LOW ESR 10k 1% NOTE: MATCH RESISTOR PAIRS R1 = R3 TO ± 0.1% R4 R2 LT1115 • TA03 1115fa 9 LT1115 TYPICAL APPLICATIO S 18V 49.9Ω INPUT R1 100Ω 3 + – 4 LT1115 2 8 1 –18V 33.2k 1% 33.2k 1% 18V 1µ F 1µ F 35V + 7 LT1097 3 4 100k 1µ F 35V 1µ F 2 6 OPTIONAL SERVO LOOP LOWERS OFFSET TO < 50µV NOTE 1: USE SINGLE POINT GROUND. NOTE 2: USE ≥ 470µF CAPACITORS AT EACH INCOMING SUPPLY TERMINAL (I.E. AT BOARD EDGE). –18V NOTE 3: FOR BETTER NOISE PERFORMANCE AT SLIGHTLY LESS DRIVE CAPABILITY: R1 = 43Ω, R2 = 392Ω DELETE C1. Figure 2. Low Noise DC Accurate x 10 Buffered Line Amplifier THD + Noise vs Frequency (Figure 2) TOTAL HARMONIC DISTORTION + NOISE (%) 0.010 TA = 25°C VS = ± 18V VIN = 500mVRMS VOUT = 5VRMS RS = 10Ω RL = 600Ω 0.001 0.0001 20 100 1k FREQUENCY (Hz) 20k LT1115 • TA07 10 + – + + + –18V 1µ F 35V U 18V + 7 6 1µ F 35V RBOOST + 1µ F 35V RL 100Ω C1 33pF IN 2N4304* 2mA R2 909Ω ~250Ω SELECT FOR 2mA LT1010CT V– V+ OUTPUT RESISTORS 1% METAL FILM CAPACITORS – BYPASS; LOWER ESR OTHER: POLYESTER OR OTHER 1µF HIGH QUALITY FILM. 35V *OR USE 2mA CURRENT SOURCE. 100k LT1115 • TA05 1115fa LT1115 TYPICAL APPLICATIO S 100pF GAIN: 40dB 30dB 24.9Ω 75Ω 2.49k 18V 0.01µF 100Ω 2 INPUT 18V – 18V 100µF 35V 18V 100k 1µF 100V 4 –18V 100µF RESISTORS 1% METAL FILM 35V CAPACITORS—BYPASS: LOW ESR OTHER: HIGH QUALITY FILM NOTE 1: USE SINGLE POINT GROUNDING TECHNIQUES Figure 3. RIAA Moving Coil “Pre-Pre” Amplifier (40/30dB Gain Low Noise Servo’d Amplifier) INTERMODULATION DISTORTION (AT 1kHz) (IMD) (%) CCIF IMD Test (Twin Tones at 13 and 14kHz) (Figure 3) 0.1 TA = 25°C VS = ± 18V RL = 100k 0.010 10µ 1µ NOISE (V) 0.001 100n 0.0001 0.1 10n 1 OUTPUT AMPLITUDE (VRMS) 10 LT1115 • TA08 20 + + 3 – U 475Ω OUTPUT TO RIAA STAGE 7 6 + 1µF 35V 1M LT1115 4 6 7 + – 3 1µF 100V LT1097 2 1M + + – 18V 1µF 35V LT1115 • TA06 Noise vs Frequency (Figure 3) TA = 25°C VS = ±18V INPUT GROUNDED 100 1k FREQUENCY (Hz) 20k NOTE: NOISE AT 1kHz REFERRED TO INPUT ~2nV LT1115 • TA09 1115fa 11 LT1115 TYPICAL APPLICATIO S 18V 1µ F 35V + 100pF 12.1Ω 2 – + MOVING COIL INPUT 100Ω 3 LT1115 4 –18V 470µF 35V Figure 4. Moving Coil Passive RIAA Phonograph Pre-Amp Deviation from RIAA Response Input at 1kHz = 232µVRMS Pre-Emphasized (Figure 4) 0.40000 0.30000 VS = ± 18V RL = 100k RS = 10Ω TA = 25°C THD + Noise vs Frequency Input at 1kHz = 232µVRMS Pre-Emphasized (Figure 4) TOTAL HARMONIC DISTORTION + NOISE (%) 0.50000 0.1 VS = ± 18V RL = 100k RS = 10Ω TA = 25°C DEVIATION (dB) 0.20000 0.10000 0.0 – 0.1000 – 0.2000 – 0.3000 – 0.4000 – 0.5000 20 0.010 100 1k FREQUENCY (Hz) 20k LT1115 • TA11 0.001 20 12 + + + 0.01µF U + 470µF 35V 2.49k RIAA NETWORK + 1µ F 7 6 R1 6081Ω 35V 3 + – 7 LT1056 6 4.7µF FILM OUTPUT 499Ω 100k 10k 1µ F 35V 1µ F 35V C1 0.1645µF 2 R2 490Ω C2 0.483µF 4 499Ω RESISTORS 1% METAL FILM CAPACITORS—BYPASS: LOW ESR OTHER: HIGH QUALITY FILM NOTE 1: 1kHz GAIN = 53dB NOTE 2: IN RIAA NETWORK VALUES SHOWN ARE MEASURED AND PRODUCE THE “DEVIATION FROM RIAA” GRAPH SHOWN. THE CALCULATED EXACT VALUES ARE: R1-6249Ω C1-0.161µF LT1115 • TA10 R2-504Ω C2-0.47µF 1k 100 FREQUENCY (Hz) 20k LT1115 • TA12 1115fa LT1115 TYPICAL APPLICATIO S 470µF 35V 2.5k REV. AUDIO 1µF 35V TAPER + 1N4002 49.9Ω 4.99Ω 2 100Ω 3 – + 7 LT1115 4 6 RED YELLOW 150Ω MICROPHONE INPUT BRN 6.19k ORANGE BLK CASE JENSEN JE-16-A/B 1N4002 –18V 18V 1µ F 10k 1µF 35V + 7 6 2 100k LT1097 3 100k 4 10Ω Figure 5. High Performance Transformer Coupled Microphone Pre-Amp Risetime of High Performance Transformer Coupled Microphone Pre-Amp (Figure 5) TOTAL HARMONIC DISTORTION + NOISE (%) 1 THD + Noise vs Frequency (Gain = 20dB) Balanced In/ Balanced Out (Figure 5) AMPLITUDE (dB) REFERRED TO 1kHz 0.1 VS = ± 18V VIN = 0.95VRMS RL = 600Ω RS = 150Ω TA = 25°C 0.010 RISETIME OF PRE-AMP AV = 20dB VIN = 400mV 2kHz SQUARE WAVE MEASURED AT SINGLEENDED OUTPUT BEFORE TRANSFORMER 0.001 0.0005 20 100 1k FREQUENCY (Hz) 20k LT1115 • TA15 + 1µF 35V –18V + – + + WHT + + U 18V + 1µF 35V 100pF 22Ω 100Ω IN V+ BOOST LT1010CT OUT V– 2.49k 10Ω OPTIONAL SINGLE-ENDED TO BALANCED OUTPUT TRANSFORMER BRN RED 2N4304** ~250Ω SELECT FOR 2mA YEL 2mA JENSEN JE-11-BM 1µ F 35V 470µF 35V 1µ F 35V RESISTORS 1% METAL FILM CAPACITORS—BYPASS: LOW ESR OTHER: HIGH QUALITY FILM NOTE: USE SINGLE POINT GROUND * JENSEN NETWORK VALUES—FACTORY SELECTED. JE-16-A/B & JE-11-BM AVAILABLE FROM: JENSEN TRANSFORMERS 10735 BURBANK BLVD. N. HOLLYWOOD, CA 91601 (213) 876-0059 ** OR USE 2mA CURRENT SOURCE LT1115 • TA13 1µ F Frequency Response (Gain = 20dB) Balanced In/ Balanced Out (Figure 5) 1.0000 0.0 – 1.000 – 2.000 – 3.000 – 4.000 – 5.000 10 VS = ± 18V VIN = 0.95VRMS RL = 600Ω RS = 150Ω TA = 25°C 100 10k 1k FREQUENCY (Hz) 100k LT1115 • TA16 1115fa 13 LT1115 TYPICAL APPLICATIO S C1 0.1µF FILM R1 2k 200Ω 200Ω 15V R2 + 1µF 35V 6 7 LT1022 5.6k –15V 3 –15V 4 15V 500Ω (20T) 2.4k 10pF MOUNT, 1N4148's IN CLOSE PROXIMITY 4.7k –15V + 470µF 35V 1µF 35V + –15V 10µF 1k 120k 2.5V LT1004's 1.2V f= 1 2πRC WHERE R1C1 = R2C2 MEASURED WITH R1 = R2 = 1.5k –15V 470µF 35V + 1µF 10k 10k + VACTEC VTL 5C10 100Ω + 15V LT1006 4 Figure 6. Ultralow THD Oscillator (Sine Wave) (< 5ppm Distortion) 14 – 1µ F 35V 7