LINEAR TECHNOLOGY LT1677 1677fa Low Noise Rail-to-Rail Precision Op Amp Manual
Contents
1. vs Frequency vs Time Noninverting Gain 100 50 0 1 Vg 15V m Z 2k 15pF c 40 we Vg 15V Vo 10Vp 0 P P g eo 25 C 2 Ay 1 10 100 58 2 z MEASUREMENT BANDWIDTH 2 125 C S 0 01 10Hz TO 80kHz 1 amp 10 5 WI Ay 100 m Ay 100 2s 5 z 3 a 5 01 30 a 25 C 5 Ay 1 E 739 125 C abe is oz P _s i 0 01 6 40 lt 2 55 C zi Ay 1 45 0 001 50 0 0001 10 100 1k 10k 100k 1M 0 1 2 3 4 20 100 1k 10k 20k FREQUENCY Hz TIME FROM OUTPUT SHORT TO GND MIN FREQUENCY Hz 1677 629 1677 G28 1677 G30 Total Harmonic Distortion and Total Harmonic Distortion and Total Harmonic Distortion and Noise vs Frequency for Inverting Noise vs Output Amplitude for Noise vs Output Amplitude for Gain Noninverting Gain Inverting Gain 0 1 p 1 1 EZ 2k 15pF s Z 2k 15pF 3 s 21 2k 15pF ur Vs 15V um Vg 15V Vg 15V Vo 10Vp p fo 1kHz 2 fo 1kHz g LAy 1 10 100 2 p Ay 1 10 100 2 p 1 10 100 MEASUREMENT BANDWIDTH MEASUREMENT BANDWIDTH MEASUREMENT BANDWIDTH amp 0 01 10Hz TO 80kHz 10Hz TO 22kHz s 10Hz TO 22kHz t tt I Av 100 Ay 2 100 t5 Ay 100 0 01 5 0 01 a a 5 Ay 10 Ay 10 amp 0 001 Arcu 0 001 Ay 1 0 001 Ay 1 lt lt lt a x sciri e2. 1 0 1 il 10 100 SOURCE RESISTANCE 1677 F08 Figure 8 Total Noise vs Source Resistance x1 Riy 1M 50 22uF 2 110k 40 100 90 eee 80 70 60 GAIN dB 30 0 01 0 1 1 10 100 FREQUENCY Hz 1677 F06a 1677 FO6b Figure 6b 0 1Hz to 10Hz Peak to Peak Noise Tester Frequency Response root of the input stage current Therefore the LT1677 s current noise will be relatively high At low frequencies the low 1 f current noise corner frequency 90Hz mini mizes current noise to some extent In most practical applications however current noise will not limit system performance This is illustrated in the Total Noise vs Source Resistance plot Figure 8 where Total Noise op amp voltage noise resistor noise current noise 2 Three regions can be identified as a function of source resistance i Rs lt 400Q Voltage noise dominates ii 4000 lt Rs lt 50k at 1kHz 4000 lt Rs lt 8k at 10Hz iii Rg gt 50k at 1kHz Rg gt 8k at 10Hz Clearly the T1677 should not be used in region iii where total system noise is at least six times higher than the voltage noise of the op amp i e the low voltage noise specification is completely wasted In this region the LT1792 or LT1793 is the best choice Resistor noise
3. VOLTAGE NOISE 20nV DIV 100 1 f CORNER 10Hz E Vom lt 14 5V 2 5 a 1 CORNER 8 5Hz Lu amp 10 I 2 Q Vom Vom 14 5V 13 5V TO 14 5 9 lt 3 9 1 f CORNER 13Hz ES 2 Vs 15V 174 252 0 1 1 10 100 1000 0 2 FREQUENCY Hz 1677 601 4 6 8 10 0 20 40 TIME SECONDS 1677 G03 60 80 100 TIME SECONDS 1677 G04 1677fa 7 TYPICAL PERFORMANCE CHARACTERISTICS Voltage Noise vs Temperature Current Noise vs Frequency P Vs 15V gt Vom 0V I 2 6 10Hz 2 2 Em a 1 f CORNER 180Hz 2 1 HH 4 Vom 1 z 4 5V TO 14 5V 1kHz 5 2 gt 3 o 1 f CORNER 60Hz Vom gt 14 5V 2 0 1 ititi 50 25 0 25 50 75 100 125 10 100 1000 10000 TEMPERATURE C FREQUENCY Hz 1677 G08 1677 G07 Input Bias Current
4. 40 C to 85 C LT16771N8 Order Options Tape and Reel Add TR Lead Free Add PBF Lead Free Tape and Reel Add TRPBF Lead Free Part Marking http www linear com leadfree Consult LTC Marketing for parts specified with wider operating temperature ranges ELECTRICAL CHARACTERISTICS The e denotes the specifications which apply over the full operating temperature range otherwise specifications are at Ta 25 C Vs 3V Vep 1 7V Vs 5V Vom Vo 2 5V unless otherwise noted SYMBOL PARAMETER CONDITIONS Note 6 MIN TYP MAX UNITS Vos Input Offset Voltage Note 11 35 90 uV 0 C TA lt 70 C e 55 150 m 40 C lt TA lt 85 C 75 210 uV Vom Vs 0 1V 150 400 uV Vom Vs 0 2V 0 C lt TA lt 70 C 180 550 uV Vom Vs 0 3V 40 C lt Ty lt 85 C e 200 650 jV Vom 0 1V 1 5 5 0 mV Vom OV 0 C lt TA lt 70 C e 1 8 6 0 mV Vom OV 40 lt Ta lt 85 C 2 0 6 5 mV AVos Average Input Offset Drift Note 10 50 8 0 40 2 0 uv C ATemp N8 e 0 20 1 5 uV G AVos Long Term Input Voltage Stability 0 3 uV Mo ATime lp Input Bias Current Note 11 2 20 nA 0 C lt TA lt 70 C e 3 35 nA 40 C Ty lt 85 C 7 50 nA Vom Vs 0 1V 0 19 0 40 pA Vom Vs 0 2V 0 C TA lt 70 C e 0 19 0 60 pA Vom Vs 0 3V 40 C lt Ty lt 85 C e 0 25 0 75 pA Vom 0 1V 1 2 0 41 uA Vom
5. FEATURES m Rail to Rail Input and Output 100 Tested Low Voltage Noise 3 2nV VHz Typ at 1kHz 4 5nV VHz Max at 1kHz Offset Voltage 60uV Max Low Vos Drift 0 2uV C Typ Low Input Bias Current 20nA Max Wide Supply Range 3V to 18V High Ayo 7V uV Min 10k High CMRR 109dB Min High PSRR 108dB Min Gain Bandwidth Product 7 2MHz Slew Rate 2 5V us Operating Temperature Range 40 C to 85 C APPLICATIONS Low Noise Signal Processing Microvolt Accuracy Threshold Detection Strain Gauge Amplifiers Tape Head Preamplifiers Direct Coupled Audio Gain Stages Infrared Detectors Battery Powered Microphones PD 171677 ECHNOLOGY Low Noise Rail to Rail Precision Op Amp DESCRIPTION The LT 1677 features the lowest noise performance avail able for a rail to rail operational amplifier 3 2nV AVHz wideband noise 1 f corner frequency of 13Hz and 90nV peak to peak 0 1Hz to 10Hz noise Low noise is combined with outstanding precision 20uV offset voltage and 0 2uV C drift 130dB common mode and power supply rejection and 7 2MHz gain bandwidth product The com mon mode range exceeds the power supply by 100mV The voltage gain of the LT1677 is extremely high 19 million typical driving a 10k load Inthe design processing and testing of the device particular attention has been paid to the optimization of the entire distribution of several key parameters Consequently the specifications have been spec
6. OV 0 C lt TA lt 70 C e 20 0 45 pA Vom OV 40 lt T4 lt 85 C e 23 0 47 pA los Input Offset Current Note 11 4 15 nA 0 C lt TA lt 70 C 5 20 nA 40 C lt TA lt 85 C e 8 40 nA Vom Vs 0 1V 6 30 nA Vom Vs 0 2V 0 C lt TA lt 70 C e 10 40 nA Vom Vs 0 3V 40 C lt Ty lt 85 C e 15 65 nA Vom 0 1V 20 100 nA Vom OV 0 C lt TA lt 70 C o 25 150 nA Vom OV 40 lt TA lt 85 C 30 160 nA 1677fa 2 CY Ure 11677 ELECTRICAL CHARACTERISTICS The e denotes the specifications which apply over the full operating temperature range otherwise specifications are at Ta 25 C Vs 3V Vem Vo 1 7V Vs 51 Vem Vo 2 5V unless otherwise noted SYMBOL PARAMETER CONDITIONS Note 6 MIN TYP MAX UNITS en Input Noise Voltage 0 1Hz to 10Hz Note 7 90 nVp p VcM Vs 180 nVp p Vom OV 600 nVp p Input Noise Voltage Density Note 8 fo 10Hz 5 2 nV VHz Vom Vs fo 10Hz 7 nV AHz Vom OV fo 10Hz 25 nV AHz fo 1kHz 3 2 45 nV VHz Vom Vs fo 1kHz 5 3 nV AHz Vom OV fo 1kHz 17 nV VHz in Input Noise Current Density fo 10Hz 1 2 pA VHz fo 1kHz 0 3 pA VHz Vom Input Voltage Range 0 1 Vs 0 1V V 0 C lt TA lt 70 C 0 Vs 0 2V V 40 C TA lt 85 C 0 Vs 0 3V V RiN Input Resistance Common Mode 2 GO Cin Input Capacitance 4 2 pF CMRR Common Mode Rejection Ratio Note 1
7. tor collectors Q28 Q29 instead of customary class A B emitter followers for the output stage Referring to the Simplified Schematic the output NPN transistor Q29 sinks the current necessary to move the output in the negative direction The change in Q29 s base emitter voltage is re flected directly to the gain node collectors of Q20 and 016 For large sinking currents the delta Vgg of 029 can domi nate the gain Figure 9 shows the change in input voltage for a change in output voltage for different load resistors connected between the supplies The gain is much higher for output voltages above ground Q28 sources current since the change in base emitter voltage of Q28 is attenu ated by the gain in the PNP portion of the output stage Therefore for positive output swings output sourcing current there is hardly any change in input voltage for any load resistance Highest gain and best linearity is achieved when the output is sourcing current which is the case in singlesupply operation whenthe load is ground referenced Figure 10 shows gains for both sinking and sourcing load currents for a worst case load of 600Q INPUT VOLTAGE 5uV DIV OUTPUT VOLTAGE V 6000 MEASURED ON TEKTRONIX 577 CURVE TRACER Figure 10 Voltage Gain Single Supply 1677fa LI MVR 15 Ll 1677 TYPICAL APPLICATIONS Microvolt Comparator with Hysteresis OUTPUT 1677 TAOS POSITIVE FEEDBACK TO ONE OF THE NULLING TERMINA
8. 0 C Ty lt 70 C 2 75 3 7 mA 40 C lt Ty lt 85 C 2 80 3 8 mA 11677 ELECTRICAL CHARACTERISTICS The e denotes the specifications which apply over the full operating temperature range otherwise specifications are at Ta 25 C Vs 15V Vem Vo OV unless otherwise noted SYMBOL PARAMETER CONDITIONS Note 6 MIN TYP MAX UNITS Vos Input Offset Voltage 20 60 uV 0 C lt TA lt 70 C e 30 120 uV 40 C lt TA lt 85 C e 45 180 uv Vom 15 1V 150 400 mu Vom 14 8V 0 C lt TA lt 70 C e 180 550 jV Vom 14 7V 40 C Ty lt 85 C e 200 650 mu Vom 15 1V 1 5 5 0 mV Vom 7 15V 0 C Ty lt 70 C 1 8 6 0 mV Vom 15V 40 lt T4 lt 85 C o 2 0 6 5 mV AVos Average Input Offset Drift Note 10 S0 8 e 0 40 2 0 uV C ATemp N8 e 0 20 1 5 uV C AVos Long Term Input Voltage Stability 0 3 uV Mo ATime lp Input Bias Current 2 20 nA 0 C lt TA lt 70 C 3 35 nA 40 C TA lt 85 C e 7 50 nA Vom 15 1V 0 19 0 40 pA Vom 14 8V 0 C lt TA lt 70 C e 0 20 0 60 pA Vom 14 7V 40 lt Ty lt 85 C e 0 25 0 75 pA Vom 15 1V 12 0 42 pA Vom 7 15V 0 C TA lt 70 C e 20 0 46 pA Vom 15V 40 lt TA lt 85 C e 23 0 48 pA los Input Offset Current 3 15 nA 0 C lt TA lt 70 C 5 20 nA 40 C lt TA lt 85 C e 8 40 nA
9. 9 0001 0 0001 0 0001 20 100 1k 10k 20k 0 3 1 10 30 0 3 1 10 30 FREQUENCY Hz OUTPUT SWING Vp p OUTPUT SWING Vp p 1677 G31 1677 G32 1677 G33 1677fa 11 APPLICATIONS INFORMATION General The LT1677 series devices may be inserted directly into OP 07 OP 27 OP 37 and sockets with or without removal of external compensation or nulling components In addi tion the LT1677 may be fitted to 741 sockets with the removal or modification of external nulling components Rail to Rail Operation To take full advantage of an input range that can exceed the supply the LT1677 is designed to eliminate phase reversal Referring to the photographs shown in Figure 1 the LT1677 is operating in the follower mode Ay 1 at asingle 3V supply The output of the LT1677 clips cleanly and recovers with no phase reversal This has the benefit of preventing lock up in servo systems and minimizing distortion components Offset Voltage Adjustment The input offset voltage of the LT1677 and its drift with temperature are permanently trimmed at wafer testing to a low level However if further adjustment of Vos is necessary the use of a 10kQ nulling potentiometer will not degrade drift with temperature Trimming to a value other than zero creates a drift of Vgs 300 uV C e g if Vos is adjusted to 300uV the change drift will be 1uV C Figure 2 Input 0 5 to 3 5V 1577 F0ta The adjustment
10. Vom 15 1V 5 25 nA Vom 14 8V 0 C lt TA lt 70 C 8 35 nA Vom 14 7V 40 C lt Ty lt 85 C e 12 60 nA Vom 15 1V 20 105 nA Vem 15V 0 C TA lt 70 C 25 160 nA Vom 15V 40 lt TA lt 85 C e 30 170 nA en Input Noise Voltage 0 1Hz to 10Hz Note 7 90 nVp p Vom 15V 180 nVp p Vom 15V 600 nVp p Input Noise Voltage Density fo 10Hz 5 2 nV VHz Vom 15V fo 10Hz 7 nV VHz Vom 15V fo 10Hz 25 nV VHz fo 1kHz 3 2 45 nV VHz Vom 15V fo 1kHz 5 3 nv VHz Vom 15 fo 1kHz 17 nV NHz n Input Noise Current Density fo 10Hz 1 2 pA NHz fo 1kHz 0 3 pA VHz Vom Input Voltage Range 15 1 15 1 V 0 C lt TA lt 70 C e 15 0 14 8 V 40 C lt TA lt 85 C e 15 0 14 7 V Rin Input Resistance Common Mode 2 GQ Cin Input Capacitance 4 2 pF 1677fa LT 5 1577 ELECTRICAL CHARACTERISTICS The e denotes the specifications which apply over the full operating temperature range otherwise specifications are at T 25 C Vg 15V Vem Vo OV unless otherwise noted SYMBOL PARAMETER CONDITIONS Note 6 MIN TYP MAX UNITS CMRR Common Mode Rejection Ratio Vom 13 3V to 14V 109 130 dB 105 124 dB Vom 15 1V to 15 1V 74 95 dB Vom 15V to 14 7V 72 91 dB PSRR Power Supply Rejection Ratio Vs 1 7V to 18V 106 130 dB 103 125 dB Vs 2 7V to 40V 108 125 dB Vs 3 1V to 40V 105 120 dB Avo
11. 045 065 130 005 7 620 8 255 1 143 1 651 3 302 0 127 05 1 651 Y 008 055 _ lt TYP 0 203 0 381 120 3048 020 325 085 MIN 0508 C08 100 018 003 8 255 0 889 54 0 457 40 076 0 381 BSC 52 N8 1002 NOTE INCHES 1 DIMENSIONS ARE THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 010 INCH 0 254mm 8 Package 8 Lead Plastic Small Outline Narrow 0 150 LTC DWG 05 08 1610 189 197 me 005 4 801 5 004 BSC gt NOTE 3 8 7 6 5 n 245 MIN wm PT sl 157 ETC TITO 8 810 3 988 01 g 5 791 6 197 hi 030 4 005 gt TYP Y RECOMMENDED SOLDER PAD LAYOUT 010 020 lt 053 069 0 254 0 508 1 346 1 752 004 010 008 010 0 203 0 254 0 eee 0 101 0 254 0 254 Tes 016 050 014 019 E x 45 0406120 0355 0483 1 270 DIMENSIONS y NCHES dus ae i MILLIMETERS 2 DRAWING NOT TO SCALE 3 THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 006 0 15mm sn 1677fa Information furnished by Linear Technology Corporation is believed to be accurate and reliable y TAR However no responsibility is assum
12. Input Bias Current Over the vs Temperature Common Mode Range 600 800 T 7 Vs 15V Ta 25 C 500 Vom 14V cog CURRENT OUT OF DUT 400 E 47 5 Vom 13 6V Vep 15 15V cc 2 c5 7 x Y INPUT BIAS CURRENT o o 0 2 2 Vom 14 3 300 ae m p E b 2 Vom 14 7V 2 Vem 15 3V 2 2 CURRENT INTO DUT 3 400 600 100 800 50 25 0 25 50 75 100 125 16 12 8 4 0 4 8 12 16 TEMPERATURE C COMMON MODE INPUT VOLTAGE V 1677 G06 1677 G09 Distribution of Input Offset Warm Up Drift Voltage Drift N8 Vg 15V Vg 15V _ 25 C 45 Ta 40 C 85 C gt M 167 PARTS 4 LOTS SO PACKAGE a e 6 2 30 N PACKAGE E 5 4 20 z amp 15 2 a lt 2 10 ce 5 0 0 0 1 2 3 4 5 1 0 06 0 2 02 06 10 14 TIME MINUTES INPUT OFFSET VOLTAGE DRIFT uV C 1677 G02 1677 G13 Input Bias Current vs Temperature Vg 15V Vow OV INPUT BIAS CURRENT nA n Co Ci O N c 125 I c 2 0 2 50 75 TEMPERATURE C 100 1677 G05 Offset Voltage Shift vs Common Mode ro on A Ha lt EN e l Ari 39V110A 145440 o Vg 1 5V TO 15V TA 25 C 5 TYPICAL PARTS 0 8 04 vt 04 Vom V V 1677 G10 2 0 Distribution of Inp
13. LT1499 10MHz 5V us Dual Quad Rail to Rail Input and Output Op Amps Precision C Load Stable LT1792 Low Noise Precision JFET Input Op Amp 4 2nV VHz 10fA VHz LT1793 Low Noise Picoampere Bias Current Op Amp 6nV VHz 1fA VHz lg 10pA Max LT1806 Low Noise 325MHz Rail to Rail Input and Output Op Amp 3 5nV VHz LT1881 LT1882 Dual Quad Rail to Rail Output Picoamp Input Precision Op Amps Ci oap to 1000pF 200pA Max LT1884 LT1885 Dual Quad Rail to Rail Output Picoamp Input Precision Op Amps 2 2MHz Bandwidth 1 2V us SR C Load is a trademark of Linear Technology Corporation Linear Technology Corporation 1630 McCarthy Blvd Milpitas CA 95035 7417 408 432 1900 FAX 408 434 0507 e www linear tech com 1677fa LT 0306 REV A PRINTED IN USA TECHNOLOGY LINEAR TECHNOLOGY CORPORATION 2000
14. specified performance from 0 C to 70 C The LT1677C is designed characterized and expected to meet specified performance from 40 C to 85 C but is not tested or QA sampled at these temperatures The LT16771 is guaranteed to meet specified performance from 40 C to 85 C Note 6 Typical parameters are defined as the 60 yield of parameter distributions of individual amplifier i e out of 100 LT1677s typically 60 op amps will be better than the indicated specification Note 7 See the test circuit and frequency response curve for 0 1Hz to 10Hz tester in the Applications Information section of the LT1677 data sheet Note 8 Noise is 100 tested at 15V supplies Note 9 Slew rate is measured in Ay 1 input signal is 7 5V output measured at 2 5V Note 10 This parameter is not 100 tested Vs 3V and 5V limits are guaranteed by correlation to Vs 15V test Note 11 Vs 5V limits are guaranteed by correlation to Vs 3V and Vg 15V tests Note 12 Vs 3V limits are guaranteed by correlation to Vs 5V and Vg 15V tests Note 13 Guaranteed by correlation to slew rate at Vs 15V GBW at Vg 3V and Vs 15V tests TYPICAL PERFORMANCE CHARACTERISTICS Voltage Noise vs Frequency 0 1Hz to 10Hz Voltage Noise 0 01Hz to 1Hz Voltage Noise
15. will look as shown in the pulsed operation diagram Figure 5 During the fast feedthrough like portion of the output the input protection diodes effectively short the output to the input and a current limited only by the output short circuit protection will be drawn by the signal generator With Rr gt 5000 the output is capable of handling the current requirements lj lt 20mA at 10V and the amplifier stays in its active mode and a smooth transition will occur Rr y 2 5V us OUTPUT LT1677 1677 F05 Figure 5 Pulsed Operation As with all operational amplifiers when Rr gt 2k a pole will be created with Rr and the amplifier s input capacitance creating additional phase shift and reducing the phase margin A small capacitor 20pF to 50pF in parallel with Rr will eliminate this problem Noise Testing The 0 1Hz to 10Hz peak to peak noise of the LT1677 is measured in the test circuit shown Figure 6a The fre quency response of this noise tester Figure 6b indicates that the 0 1Hz corner is defined by only one zero The test time to measure 0 1Hz to 10Hz noise should not exceed ten seconds as this time limit acts as an additional zero to eliminate noise contributions from the frequency band below 0 1Hz Measuring the typical 90nV peak to peak noise perfor mance of the LT1677 requires special test precautions The device should be warmed up for at least five minutes As the op amp warms up its offset
16. 0V COMMON MODE REJECTION RATIO dB 10k 100k FREQUENCY Hz 1M 10M 1677 G16 Voltage Gain vs Supply Voltage Single Supply 100 Ta 25 C RL TO GND Vom Vo Vs 2 10k OFFSET VOLTAGE CHANGE uV POWER SUPPLY REJECTION RATIO dB Ry 2k OPEN LOOP VOLTAGE GAIN V uV 0 1 0 10 20 SUPPLY VOLTAGE V 30 1677 G19 OVERSHOOT Long Term Stability of Four Representative Units N wo C 0 100 200 300 400 500 600 700 800 900 TIME HOURS 1677 G14 Power Supply Rejection Ratio vs Frequency 160 Vg 15V 140 25 C 120 100 NEGATIVE SUPPLY 80 POSITIVE SUPPLY 60 40 20 0 1 10 100 1k 10k 100k 1M FREQUENCY Hz 1677 617 Overshoot vs Load Capacitance 0 15 25 50 Rr 10k TO 2k 40 RISING 30 EDGE 20 FALLING 10 EDGE 0 10 100 1000 CAPACITANCE pF 1677 G21 1677fa 9 OFS TYPICAL PERFORMANCE CHARACTERISTICS PM GBWP SR vs Temperature PHASE MARGIN DEG QO N c
17. 1 Vg 3V Vem 0 1V to 3 1V 55 68 dB Vom OV to 2 7V 53 67 dB Vs 5V Vem 0 1V to 5 1V 60 73 dB Vom OV to 4 7V 58 72 dB PSRR Power Supply Rejection Ratio Vs 2 7V to 40V Vom Vo 1 7V 108 125 dB Vs 3 1V to 40V Vom Vo 1 7V 105 120 dB Avot Large Signal Voltage Gain Vs 3V gt 10k Vo 2 5V to 0 7V 0 6 4 V V 0 C lt Ty lt 70 C 0 4 3 V uV 40 C lt TA lt 85 C 0 4 3 V A Vs 3V RI gt 2k Vo 2 2V to 0 7V 0 5 1 V V 0 C lt TA lt 70 C 0 4 0 9 V V 40 C TA lt 85 C 0 4 0 8 V uV Vs 3V RI gt 6000 Vo 2 2V to 0 7V 0 20 0 43 V uV 0 C lt TA lt 70 C 0 15 0 40 V V 40 C lt TA lt 85 C 0 10 0 35 V uV Vs 5V RI gt 10k Vo 4 5V to 0 7V 0 8 5 V V 0 C lt TA lt 70 C 0 7 4 VAN 40 C lt TA lt 85 C 0 7 4 VAN Vs 5V RI gt 2k Vo 42V to 0 7V 0 40 0 9 V uV 0 C lt TA lt 70 C 0 35 0 8 V uV 40 C lt TA lt 85 C 0 25 0 6 V uV Vs 5V gt 6000 Vo 4 2V to 0 7V 0 35 0 67 V uV 0 C lt TA lt 70 C 0 30 0 60 V V 40 C lt TA lt 85 C 0 20 0 45 V V 1677fa 3 LT1677 ELECTRICAL CHARACTERISTICS The e denotes the specifications which apply over the full operating temperature range otherwise specifications are at Ta 25 C Vs 3V Vem Vo 1 7V Vs 51 Vom Vo 2 5V unless otherwise noted SYMBOL PARAMETER CONDITIONS Note 6 MIN TYP MAX UNITS VoL Output Voltage Swing Low Note 11 Abov
18. 7 ELECTRICAL CHARACTERISTICS The e denotes the specifications which apply over the full operating temperature range otherwise specifications are at T 25 C Vg 15V Vem Vo OV unless otherwise noted SYMBOL PARAMETER CONDITIONS Note 6 MIN TYP MAX UNITS THD Total Harmonic Distortion Ry 2k Ay 1 fp 1kHz Vo 10Vp p 0 0006 ts Settling Time 10V Step 0 1 Ay 1 5 Us 10V Step 0 01 Ay 1 6 us Ro Open Loop Output Resistance 0 80 Q Closed Loop Output Resistance Ay 100 f 10kHz 1 Q Is Supply Current 2 75 3 5 mA 0 C lt TA lt 70 C 3 00 3 9 mA 40 C lt TA lt 85 C 3 10 4 0 mA Note 1 Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime Note 2 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 4V the input current should be limited to 25mA If the common mode range exceeds either rail the input current should be limited to 10mA Note 3 A heat sink may be required to keep the junction temperature below absolute maximum Note 4 The LT1677C and 716771 are guaranteed functional over the Operating Temperature Range of 40 C to 85 C Note 5 The LT1677C is guaranteed to meet
19. LS CREATES APPROXIMATELY 5uV OF HYSTERESIS OUTPUT CAN SINK 16mA INPUT OFFSET VOLTAGE IS TYPICALLY CHANGED LESS THAN 5uV DUE TO THE FEEDBACK 3V Strain Gauge Amplitier Vout FOR TEMP COMPENSATION OF GAIN OMEGA SG 3 350LY11 3500 1 ALL OTHER RESISTORS 1 2 87 86 4999 R6 2 R72 TRIM 11 FOR BRIDGE BALANCE 1677 TA06 Precision High Side Current Sense SOURCE 3V lt Vs lt 36V ZETEX BC856B Vour Rour _ R Rout LINE 2V AMP 1677 TA07 16 11677 TYPICAL APPLICATIONS 3V Super Electret Microphone Amplifier with DC Servo 1 5V 2N3906 7H2 POLE FOR SERVO 16kHz ROLL OFF R3 1M R2 C2 80k 100pF 20kHz ROLL OFF PANASONIC TO ELECTRET HEADPHONES CONDENSER O MICROPHONE M 61 714 373 7334 15V 15V 1677 TAOS 1677fa ree 17 SIMPLIFIED SCHEMATIC SS 2294 SA M0738 AZ 0 lt SA M0138 AZ 0 lt vriog SA M0739 AZ 0 gt OA wool 01 SA M0739 AZ 0 gt wriooz 91 SA 3A08V ASL gt W94 yriooz SA 3A08V ASL lt 0 81 vi 1677fa M 18 11677 PACKAGE DESCRIPTION Dimensions in inches millimeters unless otherwise noted N8 Package 8 Lead PDIP Narrow 0 300 LTC DWG 05 08 1510 255 015 6 477 0 381 300 305
20. ZHN ZHMN001 0 LONGOYd HLOLMONVG SLEW RATE V s 75 TEMPERATURE C 1677 G22 Settling Time vs Output Step Inverting 0 01 OF x p Vour FULL SCALE yy 0 01 OF 0 1 OF FULL SCALE SETTLING TIME us SETTLING TIME us f 0 25 C 0 10 8 6 4 2 0 OUTPUT STEP V 1677 G25 Gain Phase Shift vs Frequency Vg 15V Vem 14 7V 10pF 125 C 25 C 55 C 20 A bs VOLTAGE GAIN dB 930 L4IHS 3SVHd 1 10 FREQUENCY MHz 1677 G35 Large Signal Transient Response 5us DIV 1 Vg 15 Settling Time vs Output Step Noninverting 12 Vg 15V 10 F TA 25 C gt Vout ViN 1k 8 0 01 0F 0 01 0F 6 SCALE FULL SCALE a 0 1 OF 0 1 OF 2 FULL SCALE FULL SCALE 0 10 8 6 4 20 2 4 6 8 10 OUTPUT STEP V 1677 G26 Gain Phase Shift vs Frequency 5 Vg 15V 190 Vom 14V 40 C 10pF 80 NS 125 C 25 C 55 0 60 m lt n m 40 20 0 0 1 1 10 100 FREQUENCY MHz 1677 G36 50 40 Small Signal Transient Response 50mV Gain P
21. dominates Current noise dominates 14 LT1677 APPLICATIONS INFORMATION Rail to Rail Input The LT1677 has the lowest voltage noise offset voltage and highest gain when compared to any rail to rail op amp The input common mode range for the LT1677 can exceed the supplies by at least 100mV As the common mode voltage approaches the positive rail 4 Vs 0 7V the tail current for the input pair Q1 Q2 is reduced which prevents the input pair from saturating referto the Simplified Schematic The voltage drop across the load resistors Rez Rc is reduced to less than 200mV degrad ing the slew rate bandwidth voltage noise offset voltage and input bias current the cancellation is shut off When the input common mode range goes below 1 5V above the negative rail the NPN input pair Q1 Q2 shuts off and the PNP input pair Q8 Q9 turns on The offset voltage input bias current voltage noise and bandwidth are also degraded The graph of Offset Voltage Shift vs Common Mode shows where the knees occur by display ing the change in offset voltage The change over points aretemperature dependent see the graph Common Mode Range vs Temperature INPUT VOLTAGE 50uV DIV 15 10 5 0 5 10 15 Ta 25 C Vg 15 CONNECTED TO 0V MEASURED ON TEKTRONIX 577 CURVE TRACER Figure 9 Voltage Gain Split Supply OUTPUT VOLTAGE V Rail to Rail Output The rail to rail output swing is achieved by using transis
22. e GND Isink 0 1mA 110 170 mV 0 C TA lt 70 C 125 200 mV 40 C TA lt 85 C e 130 230 mV Above GND Isink 2 5mA 170 250 mV 0 C lt TA lt 70 C 195 320 mV 40 C lt TA lt 85 C e 205 350 mV Above GND 10mA 370 500 mV 0 C TA lt 70 C 440 600 mV 40 C TA lt 85 C 465 650 mV Vou Output Voltage Swing High Note 11 Below Vs Isource 0 1mA 75 170 mV 0 C lt TA lt 70 C 85 200 mV 40 C TA lt 85 C e 93 250 mV Below Vs Isource 2 5mA 170 300 mV 0 C TA lt 70 C 195 350 mV 40 C TA lt 85 C 205 375 mV Below Vs Isource 10mA 450 700 mV 0 C TA x 70 C 510 800 mV 40 C TA lt 85 C 525 850 mV lsc Output Short Circuit Current Note 3 Vs 3V 15 22 mA 0 C lt TA lt 70 C e 14 20 mA 40 C lt TA lt 85 C 13 19 Vs 5V 20 29 mA 0 C lt Ta lt 70 C 18 27 40 C lt Ty lt 85 C 17 25 SR Slew Rate Note 13 Ay 1 17 2 5 V us Ry gt 10k 0 C lt TA lt 70 C 1 5 2 3 V us gt 10k 409C lt TA lt 85 C 1 2 2 0 V us GBW Gain Bandwidth Product Note 11 fo 100kHz 45 7 2 MHz fo 100kHz 0 C lt TA lt 70 C 3 8 6 2 MHz fo 100kHz 40 C lt T4 lt 85 C 3 7 5 8 MHz ts Settling Time 2V Step 0 1 Ay 1 2 1 us 2V Step 0 01 Ay 1 3 5 us Ro Open Loop Output Resistance loyt 0 80 Q Closed Loop Output Resistance Ay 100 f 10kHz 1 Q Is Supply Current Note 12 2 60 3 4 mA
23. ed for its use Linear Technology Corporation makes no represen TECHNOLOGY tation that the interconnection ofits circuits as described herein will not infringe on existing patent rights TYPICAL APPLICATION This 2 wire remote Geophone preamp operates on a gain of 107 Components R5 and Q1 convert the voltage current loop principle and so has good noise immunity into a current for transmission back to R10 which con Quiescent current is 10mA for a Vour of 2 5V Excitation verts it into a voltage again The LM334 and 2N3904 will cause AC currents about this point of 4mA fora not temperature compensated so the DC output contains Vout of 1V max The op amp is configured for a voltage temperature information 2 Wire Remote Geophone Preamp LINEAR TECHNOLOGY GEOSPACE GS 20DX Ri 6300 GEOPHONE wwwW geospacecorp com default htm 713 939 7093 R2 R3IIR4 497 R9 20 1677 TA04 R1 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1028 LT1128 Ultralow Noise Precision Op Amps Lowest Noise 0 85nV VHz LT1115 Ultralow Noise Low distortion Audio Op Amp 0 002 THD Max Noise 1 2nV VHz LT1124 LT1125 Dual Quad Low Noise High Speed Precision Op Amps Similar to LT1007 LT1126 LT1127 Dual Quad Decompensated Low Noise High Speed Precision Op Amps Similar to LT1037 LT1226 Low Noise Very High Speed Op Amp 1GHz 2 6nV VHz Gain of 25 Stable LT1498
24. hase Shift vs Frequency Vez Vom OV 10pF 80 125 C 25 C E t Ni 55 C 60 a 40 GAIN PHASE N S x E 20 4 0 Y 20 0 1 1 10 100 FREQUENCY MHz 1677 G34 Output Voltage Swing vs Load Current Vs 0 0 1 Vs 15V 0 2 2 03 co 0 4 05 0 6 a 0 7 gt 05 5 0 4 03 e 0 2 0 1 Vs 0 10 8 6 4 2 0 2 4 6 8 10 ISINK ISOURCE OUTPUT CURRENT mA 1677 G27 11677 TYPICAL PERFORMANCE CHARACTERISTICS Closed Loop Output Impedance Output Short Circuit Current Total Harmonic Distortion and Noise vs Frequency for
25. range with a 10kQ pot is approximately 2 5mV If less adjustment range is needed the sensitiv ity and resolution of the nulling can be improved by using a smaller pot in conjunction with fixed resistors The example has an approximate null range of 200uV Figure 3 OUTPUT 1 5V 1677 F02 Figure 2 Standard Adjustment 1 5V 1677 F03 Figure 3 Improved Sensitivity Adjustment LT1677 Output 3V 2V oV 0 5 1577 FO1b Figure 1 Voltage Follower with Input Exceeding the Supply Voltage Vs 3V 1677fa 12 LI MVR 11677 APPLICATIONS INFORMATION Offset Voltage and Drift Thermocouple effects caused by temperature gradients across dissimilar metals at the contacts to the input terminals can exceed the inherent drift of the amplifier unless proper care is exercised Air currents should be minimized package leads should be short the two input leads should be close together and maintained atthe same temperature The circuit shown to measure offset voltage is also used as the burn in configuration for the LT1677 with the supply voltages increased to 20V Figure 4 50k Vout Vout 1000Vos RESISTORS MUST HAVE LOW THERMOELECTRIC POTENTIAL 1677 F04 Figure 4 Test Circuit for Offset Voltage and Offset Voltage Drift with Temperature Unity Gain Buffer Application When Rr lt 100Q and the input is driven with a fast large signal pulse gt 1V the output waveform
26. t Large Signal Voltage Gain gt 10k Vo 14V 7 19 V uV 0 C lt TA lt 70 C 4 13 V uV 40 C lt Ty lt 85 C 3 8 V uV Ri gt 2k Vo 13 5V 0 50 0 75 V uV 0 C lt Ta lt 70 C 0 30 0 67 V uV 40 C lt TA lt 85 C 0 15 0 24 V uV Ry gt 6000 Vo 10V 0 2 0 5 V uV VoL Output Voltage Swing Low Above Vs Isink 0 1mA 110 170 mV 0 C lt Ta lt 70 C 125 200 mV 40 C lt TA lt 85 C 130 230 mV Above Vs Isink 2 5mA 170 250 mV 0 C lt Ta lt 70 C 195 320 mV 40 C lt TA lt 85 C 205 350 mV Above Vs Isink 10mA 370 500 mV 0 C TA x 70 C 440 600 mV 40 C lt TA lt 85 C 450 650 mV Vou Output Voltage Swing High Below Vs Isqurce 0 1mA 110 170 mV 0 C TA lt 70 C 130 200 mV 40 C lt TA lt 85 C 140 250 mV Below Vs lsouncE 2 5mA 210 300 mV 0 C TA lt 70 C 240 350 mV 40 C lt TA lt 85 C 250 375 mV Below Vs 1 10mA 520 700 mV 0 C TA lt 70 C 590 800 mV 40 C lt TA lt 85 C 620 850 mV lsc Output Short Circuit Current Note 3 25 35 mA 0 C lt TA lt 70 C 20 30 mA 40 C lt TA lt 85 C 18 28 mA SR Slew Rate Ry 10k Note 9 1 7 2 5 V us gt 10k Note 9 0 C lt T4 lt 70 C 1 5 2 3 V us R gt 10k Note 9 40 lt T4 lt 85 C 1 2 2 0 V us GBW Gain Bandwidth Product fo 100kHz 45 7 2 MHz 100kHz 0 C lt T4 lt 70 C 3 8 6 2 MHz fo 100kHz 40 C lt lt 85 C 3 7 5 8 MHz 1677fa 6 AC Wee 1167
27. tacularly improved compared to competing rail to rail amplifiers 4J LT LTC and LTM are registered trademarks of Linear Technology Corporation All other trademarks are the property of their respective owners TYPICAL APPLICATION 3V Electret Microphone Amplifier Ay 100 R3 y M R1 C1 R2 10k gt 0 68uF 10k 1 5V PANASONIC ELECTRET CONDENSER MICROPHONE WM 61 www panasonic com pic 714 373 7334 TO PA OR HEADPHONES O 1677 01 Distribution of Offset Voltage TA 25 C Vg 15V PERCENT OF UNITS um 30 20 10 0 10 20 30 40 INPUT OFFSET VOLTAGE uV 1677 TA02 1677fa 1 bL ABSOLUTE MAXIMUM RATINGS PACKAGC ORDER INFORMATION Note 1 TOP VIEW Supply Voltage RR 22V sn ay Input Voltages Note 2 0 3V Beyond Either Rail nG 7 s Differential Input Current Note 2 25mA e eu Output Short Circuit Duration Note 3 Indefinite is ii Storage Temperature Range 659C to 150 C BiEADPDIP BiEADPLASTICSO Lead Temperature Soldering 10 sec 300 C qus ey ir As nr ile ane ORDER PART NUMBER 8 PART MARKING LT1677C Note 4 40 C to 85 C TAG ZF usu sassa so 40 C to 85 C LT1677088 1677 Specified Temperature Range 111677158 16771 LT1677C Note 5 aaa 40 C to 85 C LT1677CN8 UTA GTZ
28. ut Offset Voltage Drift 80 8 Vg 15V Ta 40 C TO 85 C 201 PARTS 5 LOTS PERCENT OF UNITS 0 08 0 4 0 04 08 12 16 20 INPUT OFFSET VOLTAGE DRIFT uV C 1677 G37 1677fa 11677 TYPICAL PERFORMANCE CHARACTERISTICS VOLTAGE OFFSET uV Vos vs Temperature of Representative Units 140 120 100 80 60 40 20 Vg 15V Vom 0V 50 8 N8 1 OFFSET VOLTAGE mV 80 55 35 15 5 25 45 65 85 105 125 TEMPERATURE C 1677 G11 Supply Current vs Supply Voltage 4 3 LLI 2 c zi R2 2 72 1 0 5 10 15 20 SUPPLY VOLTAGE V 1677 G15 Voltage Gain vs Frequency 180 Vg 151 Ta 25 C 140 V OV 100 lt c5 Vem Vee NWN Vom Voc 60 gt 20 20 0 01 1 100 10k 1 100M FREQUENCY Hz 1677 G18 Common Mode Range vs Temperature t 295 Vs 2 5V TO 15V 125 G AN 39V L10A 145440 1 t 1 1 25 1 1 t 1 i 0 8 0 4 vt Vom Vs 5 10 V 10 20 Vom Vs V 1677 G12 Common Mode Rejection Ratio vs Frequency Vs 15V Ta 25 C Vom
29. voltage changes typically 3uV due to its chip temperature increasing 10 C to 20 C from the moment the power supplies are turned on In theten second measurement interval these temperature induced effects can easily exceed tens of nanovolts m For similar reasons the device must be well shielded from air currents to eliminate the possibility of thermoelectric effects in excess of a few nanovolts which would invalidate the measurements Sudden motion in the vicinity of the device can also feedthrough to increase the observed noise Current noise is measured in the circuit shown in Figure 7 and calculated by the following formula 1 2 eno 180nv 101 In Mo 101 The LT1677 achieves its low noise in part by operating the input stage at 100uiA versus the typical 10uA of most other op amps Voltage noise is inversely proportional while current noise is directly proportional to the square 1677fa 13 E1677 APPLICATIONS INFORMATION 0 1uF VOLTAGE GAIN 50 000 DEVICE UNDER TEST NOTE ALL CAPACITOR VALUES ARE FOR NONPOLARIZED CAPACITORS ONLY Eno 1677 F07 Figure 7 t z BS H N DAAN oz SOURCE RESISTANCE 2R 100 TOTAL NOISE DENSITY nV VHz NOISE ONLY
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LINEAR TECHNOLOGY LT1677 1677fa Low Noise Rail to Rail Precision Op Amp Manual