LT1115 Ultralow Noise, Low Distortion, Audio Op Amp FEATURES DESCRIPTIO Voltage Noise: 1.2nV/ Hz Max at 1kHz The LT 1115 is the lowest noise audio operational ampli- 0.9nV/ Hz Typ at 1kHz fier available. This ultralow noise performance (0.9nV/Hz Voltage and Current Noise 100% Tested at 1kHz) is combined with high slew rates (>15V/s) and Gain-Bandwidth Product: 40MHz Min very low distortion specifications. Slew Rate: 10V/s Min The RIAA circuit shown below using the LT1115 has very Voltage Gain: 2 Million Min low distortion and little deviation from ideal RIAA Low THD at 10kHz, A = 10, R = 600 : 0.002% L V response (see graph). V = 7V RMS O Low IMD, CCIF Method, A = +10: 0.002% , LTC and LT are registered trademarks of Linear Technology Corporation. V R = 600 L V = 7V O RMS U 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 RIAA Phonograph Preamplifier (40/60db Gain) 18V 18V Measured Deviation from RIAA + + 1F 1F R BOOST 35V 35V 49.9 Response. lnput at 1kHz = 1mV 2 RMS 3 7 INPUT + Pre-Emphasized 4 100 562 A1 1 6 A2 5 OUTPUT R 47.5k (MM) LT1115 LT1010CT 1.0000 IN C IN 2 V = 18V 100 (MC) S 2N4304* (SELECT 0.80000 R =25 4 R 3 L S ~250 PER 3900pF T =25C 25k A COM SELECT 0.60000 PHOTO 2mA FOR 2mA CART- 0.40000 RIDGE) 1F 1F 0.20000 35V 18V 35V 18V MEASURED 0.0 499 17.8k 210k COMPUTER 0.2000 + V 18V SIMULATED 0.4000 + 330pF 22.6 470F 0.6000 35V COM 0.8000 15nF + OPENMM 1.000 470F 210 20 100 1k 10k 50k CLOSEDMC 35V 3900pF SINGLE RESISTORS 1% FREQUENCY (Hz) POINT *OR USE 2mA CURRENT SOURCE LT1115 TA02 V 18V + BOARD 82.5k MM = MOVING MAGNET GROUND MC = MOVING COIL NOTE: BYPASS SUPPLIES WITH LOW ESR CAPS 2200F 4.7F LT1115 TA01 OTHER CAPS: HIGH QUALITY FILM 16V FILM 1115fa 1 DEVIATION (dB) + + U ULT1115 ABSOLUTE AXI U RATI GS (Note 1) Operating Temperature Range ..................... 0C to 70C Supply Voltage ...................................................... 22V Storage Temperature Range ..................65C to 150C Differential Input Current (Note 5) ...................... 25mA Lead Temperature (Soldering, 10 sec).................. 300C Input Voltage ............................ Equal to Supply Voltage Output Short-Circuit Duration .......................... Indefinite PACKAGE DESCRIPTIO TOP VIEW ORDER ORDER PART NUMBER PART NUMBER NC 1 16 NC TOP VIEW NC 2 15 NC V OS V OS LT1115CN8 LT1115CSW 1 8 TRIM 3 14 TRIM TRIM TRIM + IN 2 7 + V IN 4 13 V + OUT +IN 3 6 + +IN 5 12 OUTPUT OVER- V 4 5 V 6 11 COMP OVERCOMP N PACKAGE NC 7 10 NC 8-LEAD PDIP NC 8 9 NC T = 115C, = 130C/W JMAX JA SW PACKAGE 16-LEAD PLASTIC SO T = 115C, = 130C/W MAX JA LT1115 POI01 Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS V = 18V, T = 25C, unless otherwise noted. S A SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS THD Total Harmonic Distortion at 10kHz A = 10, V = 7V , R = 600 < 0.002 % RMS L v O IMD Inter-Modulation Distortion (CCIF) A = 10, V = 7V , R = 600 < 0.0002 % RMS L v O V Input Offset Voltage (Note 2) 50 200 V OS I Input Offset Current V = 0V 30 200 nA CM OS I Input Bias Current V = 0V 50 380 nA CM B e Input Noise Voltage Density f = 10Hz 1.0 nV/Hz n o f = 1000Hz, 100% tested 0.9 1.2 nV/Hz o Wideband Noise DC to 20kHz 120 nV RMS Corresponding Voltage Level 136 dB re 0.775V i Input Noise Current Density f = 10Hz 4.7 pA/Hz n o (Note 3) f = 1000Hz, 100% tested 1.2 2.2 pA/Hz o Input Resistance Common Mode 250 M Differential Mode 15 k Input Capacitance 5pF Input Voltage Range 13.5 15.0 V 1115fa 2 U U WWW