View LT1056N8_291152.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

LT1055/LT1056 Precision, High Speed, JFET Input Operational Amplifiers
FEATURES
s s s
DESCRIPTIO
s
Guaranteed Offset Voltage: 150V Max -55C to 125C: 500V Max Guaranteed Drift: 4V/C Max Guaranteed Bias Current 70C: 150pA Max 125C: 2.5nA Max Guaranteed Slew Rate: 12V/s Min
The LT(R)1055/LT1056 JFET input operational amplifiers combine precision specifications with high speed performance. For the first time, 16V/s slew rate and 6.5MHz gain bandwidth product are simultaneously achieved with offset voltage of typically 50V, 1.2V/C drift, bias currents of 40pA at 70C and 500pA at 125C. The 150V maximum offset voltage specification is the best available on any JFET input operational amplifier. The LT1055 and LT1056 are differentiated by their operating currents. The lower power dissipation LT1055 achieves lower bias and offset currents and offset voltage. The additional power dissipation of the LT1056 permits higher slew rate, bandwidth and faster settling time with a slight sacrifice in DC performance. The voltage-to-frequency converter shown below is one of the many applications which utilize both the precision and high speed of the LT1055/LT1056. For a JFET input op amp with 23V/s guaranteed slew rate, refer to the LT1022 data sheet.
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATIO S
s s s s s s s
Precision, High Speed Instrumentation Logarithmic Amplifiers D/A Output Amplifiers Photodiode Amplifiers Voltage-to-Frequency Converters Frequency-to-Voltage Converters Fast, Precision Sample-and-Hold
TYPICAL APPLICATIO
4.7k 15V
0kHz to 10kHz Voltage-to-Frequency Converter
3M
140
0.001 (POLYSTYRENE)
120
0V TO 10V INPUT
2
+ -
33pF
0.1F
22k
LT1056 3 4 -15V
6
1.5k
NUMBER OF UNITS
10kHZ TRIM 5k
15V 7
OUTPUT 1Hz TO 10kHz 0.005% LINEARITY
3.3M 2N3906 = 1N4148 *1% FILM -15V 0.1F THE LOW OFFSET VOLTAGE OF LT1056 CONTRIBUTES ONLY 0.1Hz OF ERROR WHILE ITS HIGH SLEW RATE PERMITS 10kHz OPERATION.
LM329
20 0 -400 200 -200 400 0 INPUT OFFSET VOLTAGE (V)
LT1055/56 TA02
LT1055/56 TA01
U
Distribution of Input Offset Voltage (H Package)
VS = 15V TA = 25C 634 UNITS TESTED FROM THREE RUNS 50% TO 60V 100 80 60 40
10556fb
U
U
1
LT1055/LT1056
ABSOLUTE MAXIMUM RATINGS
Supply Voltage ...................................................... 20V Differential Input Voltage ....................................... 40V Input Voltage ......................................................... 20V Output Short-Circuit Duration .......................... Indefinite Operating Temperature Range LT1055AM/LT1055M/LT1056AM/ LT1056M (OBSOLETE) .............. -55C to 125C
PACKAGE/ORDER INFORMATION
TOP VIEW BAL 1 -IN 2 +IN 3 V- 4 N8 PACKAGE 8-LEAD PDIP
TJMAX = 150C, JA = 130C/ W
8 7 6 5
N/C V+ OUT BAL
ORDER PART NUMBER LT1055CN8 LT1056CN8
TOP VIEW NC 8 BALANCE 1 -IN 2 +IN 3 7 V+ 6 OUT
5 BALANCE 4 V- H PACKAGE 8-LEAD TO-5 METAL CAN
TJMAX = 150C, JA = 150C/ W, JC = 45C/ W
OBSOLETE PACKAGE
Consider the N8 Package for Alternate Source
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER VOS Input Offset Voltage (Note 2) CONDITIONS LT1055 H Package LT1056 H Package LT1055 N8 Package LT1056 N8 Package Fully Warmed Up Fully Warmed Up VCM = 10V
TA = 25C. VS = 15V, VCM = 0V unless otherwise noted.
LT1055AM/LT1056AM LT1055AC/LT1056AC MIN TYP MAX -- -- -- -- -- -- -- 50 50 -- -- 2 10 30 150 180 -- -- 10 50 130 LT1055M/LT1056M LT1055CH/LT1056CH LT1055CN8/LT1056CN8 MIN TYP MAX -- -- -- -- -- -- -- 70 70 120 140 2 10 30 400 450 700 800 20 50 150
IOS IB
Input Offset Current Input Bias Current
2
U
U
W
WW U
W
(Note 1)
LT1055AC/LT1055C/LT1056AC/ LT1056C ................................................ 0C to 70C Storage Temperature Range All Devices ...................................... - 65C to 150C Lead Temperature (Soldering, 10 sec).................. 300C
TOP VIEW BAL 1 -IN 2 +IN 3 V- 4 8 7 6 5 N/C V+ OUT BAL
ORDER PART NUMBER LT1055S8 LT1056S8 S8 PART MARKING 1055 1056
S8 PACKAGE 8-LEAD PLASTIC SO
TJMAX = 150C, JA = 150C/ W
ORDER PART NUMBER LT1055ACH LT1055CH LT1055AMH LT1055MH LT1056ACH LT1056CH LT1056AMH LT1056MH
UNITS V V V V pA pA pA
10556fb
LT1055/LT1056
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER Input Resistance:Differential CONDITIONS
TA = 25C. VS = 15V, VCM = 0V unless otherwise noted.
LT1055AM/LT1056AM LT1055AC/LT1056AC MIN TYP MAX -- -- -- -- -- -- -- -- -- 150 130 11 86 90 12 10 12 -- -- -- -- -- 1012 1012 1011 4 1.8 2.5 28 14 1.8 400 300 12 100 106 13.2 13 16 5.0 6.5 2.8 5.0 5 -- -- -- -- -- -- 50 20 4 -- -- -- -- -- -- -- -- -- -- 4.0 6.5 -- LT1055M/LT1056M LT1055CH/LT1056CH LT1055CN8/LT1056CN8 MIN TYP MAX -- -- -- -- -- -- -- -- -- 120 100 11 83 88 12 7.5 9.0 -- -- -- -- -- 1012 1012 1011 4 2.0 2.8 30 15 1.8 400 300 12 98 104 13.2 12 14 4.5 5.5 2.8 5.0 5 -- -- -- -- -- -- 60 22 4 -- -- -- -- -- -- -- -- -- -- 4.0 7.0 --
UNITS pF VP-P VP-P nV/Hz nV/Hz fA/Hz V/mV V/mV V dB dB V V/s V/s MHz MHz mA mA mV
Common Mode VCM = -11V to 8V VCM = 8V to 11V Input Capacitance en Input Noise Voltage Input Noise Voltage Density In AVOL Input Noise Current Density Large-Signal Voltage Gain Input Voltage Range CMRR PSRR VOUT SR GBW IS Common Mode Rejection Ratio Power Supply Rejection Ratio Output Voltage Swing Slew Rate Gain Bandwidth Product Supply Current Offset Voltage Adjustment Range RPOT = 100k f = 1MHz VCM = 11V VS = 10V to 18V RL = 2k LT1055 LT1056 LT1055 LT1056 LT1055 LT1056 0.1Hz to 10Hz LT1055 LT1056
f0 = 10Hz (Note 3) f0 = 1kHz (Note 4) f0 = 10Hz, 1kHz (Note 5) V0 = 10V RL = 2k RL = 1k
The q denotes the specifications which apply over the temperature range 0C TA 70C. VS = 15V, VCM = 0V unless otherwise noted.
LT1055AC LT1056AC TYP 100 100 -- -- 1.2 -- 10 14 30 40 250 100 105 13.1 LT1055CH/LT1056CH LT1055CN8/LT1056CN8 MIN TYP MAX -- -- -- -- -- -- -- -- -- -- 60 82 87 12 140 140 250 280 1.6 3.0 16 18 40 50 250 98 103 13.1 750 800 1250 1350 8.0 12.0 80 100 200 240 -- -- -- --
SYMBOL PARAMETER VOS Input Offset Voltage (Note 2)
CONDITIONS LT1055 H Package LT1056 H Package LT1055 N8 Package LT1056 N8 Package H Package (Note 6) N8 Package (Note 6) Warmed Up TA = 70C Warmed Up TA = 70C VCM = 10.5V VS = 10V to 18V RL = 2k LT1055 LT1056 LT1055 LT1056
q q q q q q q q q q q q q q
MIN -- -- -- -- -- -- -- -- -- -- 80 85 89 12
MAX 330 360 -- -- 4.0 -- 50 70 150 80 -- -- -- --
UNITS V V V V V/C V/C pA pA pA pA V/mV dB dB V
10556fb
Average Temperature Coefficient of Input Offset Voltage IOS IB AVOL CMRR PSRR VOUT Input Offset Current Input Bias Current Large-Signal Voltage Gain Common Mode Rejection Ratio Power Supply Rejection Ratio Output Voltage Swing
VO = 10V, RL = 2k
3
LT1055/LT1056
The q denotes the specifications which apply over the temperature range -55C TA 125C. VS = 15V, VCM = 0V, unless otherwise noted.
LT1055AM LT1056AM TYP 180 180 1.3 LT1055M LT1056M TYP 250 250 1.8
ELECTRICAL CHARACTERISTICS
CONDITIONS
SYMBOL PARAMETER VOS Input Offset Voltage (Note 2) Average Temperature Coefficient of Input Offset Voltage IOS IB AVOL CMRR PSRR VOUT Input Offset Current Input Bias Current Large-Signal Voltage Gain Common Mode Rejection Ratio Power Supply Rejection Ratio Output Voltage Swing
MIN LT1055 LT1056
q q q
MAX 500 550 4.0
MIN -- -- --
MAX 1200 1250 8.0
UNITS V V V/C
-- -- --
(Note 6)
Warmed Up TA = 125C Warmed Up TA = 125C VCM = 10.5V
LT1055 LT1056 LT1055 LT1056
q q q q q q q q
-- -- -- -- 40 85 88 12
0.20 0.25 0.4 0.5 120 100 104 12.9
1.2 1.5 2.5 3.0 -- -- -- --
-- -- -- -- 35 82 86 12
0.25 0.30 0.5 0.6 120 98 102 12.9
1.8 2.4 4.0 5.0 -- -- -- --
nA nA nA nA V/mV dB dB V
VO = 10V, RL = 2k VS = 10V to 17V RL = 2k
TA = 25C. VS = 15V, VCM = 0V unless otherwise noted.
SYMBOL PARAMETER VOS IOS IB Input Offset Voltage (Note 2) Input Offset Current Input Bias Current Input Resistance Differential Common Mode Fully Warmed Up Fully Warmed Up VCM = 10V VCM = -11V to 8V VCM = 8V to 11V 0.1Hz to 10Hz fO = 10Hz (Note 4) fO = 1kHz (Note 4) fO = 10Hz, 1kHz (Note 5) VO = 10V RL = 2k RL = 1k 120 100 11 VCM = 11V VS = 10V to 18V RL = 2K LT1055 LT1056 f = 1MHz LT1055 LT1056 LT1055 LT1056 RPOT = 100k 83 88 12 7.5 9.0 LT1055 LT1056 CONDITIONS LT1055CS8/LT1056CS8 MIN TYP MAX 500 5 30 30 0.4 0.4 0.05 4 2.5 3.5 35 15 2.5 400 300 12 98 104 13.2 12 14 4.5 5.5 2.8 5.0 5 4.0 7.0 70 22 10 1500 30 100 150 UNITS V pA pA pA T T T pF VP-P VP-P nV/Hz nV/Hz fA/Hz V/mV V/mV V dB dB V V/s V/s MHz MHz mA mA mV
10556fb
Input Capacitance en Input Noise Voltage Input Noise Voltage Density in AVOL Input Noise Current Density Large-Signal Voltage Gain Input Voltage Range CMRR PSRR VOUT SR GBW IS Common Mode Rejection Ratio Power Supply Rejection Ratio Output Voltage Swing Slew Rate Gain Bandwidth Product Supply Current Offset Voltage Adjustment Range
4
LT1055/LT1056
The q denotes the specifications which apply over the temperature range 0C TA 70C. VS = 15V, VCM = 0V, unless otherwise noted.
SYMBOL PARAMETER VOS IOS IB AVOL CMRR PSRR VOUT Input Offset Voltage (Note 2) Average Temperature Coefficient of Input Offset Voltage Input Offset Current Input Bias Current Large-Signal Voltage Gain Common Mode Rejection Ratio Power Supply Rejection Ratio Output Voltage Swing Warmed Up, TA = 70C Warmed Up, TA = 70C VO = 10V, RL = 2k VCM = 10.5V VS = 10V to 18V RL = 2K CONDITIONS q q q q q q q q 60 82 87 12 LT1055CS8/LT1056CS8 MIN TYP MAX 800 4 18 60 250 98 103 13.1 2200 15 150 400 UNITS V V/C pA pA V/mV dB dB V
ELECTRICAL CHARACTERISTICS
For MIL-STD components, please refer to LTC883 data sheet for test listing and parameters. Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Offset voltage is measured under two different conditions: (a) approximately 0.5 seconds after application of power; (b) at TA = 25C only, with the chip heated to approximately 38C for the LT1055 and to 45C for the LT1056, to account for chip temperature rise when the device is fully warmed up.
Note 3: 10Hz noise voltage density is sample tested on every lot of A grades. Devices 100% tested at 10Hz are available on request. Note 4: This parameter is tested on a sample basis only. Note 5: Current noise is calculated from the formula: in = (2qlB)1/2, where q = 1.6 * 10 -19 coulomb. The noise of source resistors up to 1G swamps the contribution of current noise. Note 6: Offset voltage drift with temperature is practically unchanged when the offset voltage is trimmed to zero with a 100k potentiometer between the balance terminals and the wiper tied to V+. Devices tested to tighter drift specifications are available on request.
10556fb
5
LT1055/LT1056 TYPICAL PERFORMANCE CHARACTERISTICS
Input Bias and Offset Currents vs Temperature
INPUT BIAS CURRENT, TA = 25C, TA = 70C (pA)
1000 INPUT BIAS AND OFFSET CURRENT (pA)
300
VS = 15V VCM = 0V WARMED UP BIAS OR OFFSET CURRENTS MAY BE POSITIVE OR NEGATIVE BIAS CURRENT
40 0 -40
100
A TA = 25C A
400 0 -400
NUMBER OF INPUTS
30
10 OFFSET CURRENT 3
0
25 75 100 50 AMBIENT TEMPERATURE (C)
Distribution of Offset Voltage Drift with Temperature (H Package)*
140 120
CHANGE IN OFFSET VOLTAGE (V)
80
OFFSET VOLTAGE CHANGE V)
VS = 15V 634 UNITS TESTED FROM THREE RUNS
BATTERY VOLTAGE (V)
100 80 60 40 20 0 4 6 8 10 -10 -8 -6 -4 -2 0 2 OFFSET VOLTAGE DRIFT WITH TEMPERATURE (V/C) *DISTRIBUTION IN THE PLASTIC (N8) PACKAGE IS SIGNIFICANTLY WIDER.
0.1Hz to 10Hz Noise
0.1Hz TO 10Hz PEAK-TO-PEAK NOISE (V/P-P) 10 7 5
NOISE VOLTAGE (1V/DIVISION)
70 PEAK-TO-PEAK NOISE 50
LT1056
RMS NOISE VOLTAGE DENSITY (nV/Hz)
LT1055
0
2
6 4 TIME (SECONDS)
6
UW
LT1055/56 G01
Input Bias Current Over the Common Mode Range
120 80 TA = 125C TA = 70C VS = 15V WARMED UP 1200
INPUT BIAS CURRENT, TA = 125C (pA)
Distribution of Input Offset Voltage (N8 Package)
160 140
800
VS = 15V TA = 25C 550 UNITS TESTED FROM 120 TWO RUNS (LT1056) 100 80 60 40 20
50% YIELD TO 140V
TA = 70C -80 B B
TA = 125C -800
125
-120 -15
A = POSITIVE INPUT CURRENT B = NEGATIVE INPUT CURRENT 15
-1200
-5 0 5 10 -10 COMMON MODE INPUT VOLTAGE (V)
0 -800 -600 -400 -200 0 200 400 600 800 INPUT OFFSET VOLTAGE (V)
LT1055/56 G03
LT1055/56 G02
Warm-Up Drift
100 VS = 15V TA = 25C
50 40 30 20 10 0 -10 -20 -30 -40 -50
Long Term Drift of Representative Units
VS = 15V TA = 25C
50% TO 1.5V/C
60 LT1056CN8 40 LT1055CN8 LT1056 H PACKAGE LT1055 H PACKAGE 0 0 1 3 4 2 TIME AFTER POWER ON (MINUTES) 5
20
0
1
3 2 TIME (MONTHS)
4
5
LT1055/56 G05
LT1055/56 GO6
LT1055/56 G04
Noise vs Chip Temperature
100 RMS NOISE VOLTAGE DENSITY (nV/Hz)
1000
Voltage Noise vs Frequency
VS = 15V TA = 25C
300
3 f0 = 10kHz 2 f0 = 1kHz
30 20
100
LT1056 1/f CORNER = 28HZ
30 LT1055 1/f CORNER = 20HZ 10 1 3 10 100 30 FREQUENCY (Hz) 300 1000
1 10 20 30 50 60 40 CHIP TEMPERATURE (C) 70
8
10
10 80
LT1055/56 GO7
LT1055/56 G08
LT1055/56 G09
10556fb
LT1055/LT1056 TYPICAL PERFORMANCE CHARACTERISTICS
LT1056 Large-Signal Response Small-Signal Response LT1055 Large-Signal Response
5V/DIV
AV = 1, CL = 100pF, 0.5s/DIV
LT1055/56 G10
20mV/DIV
5V/DIV
Undistorted Output Swing vs Frequency
30
30
PEAK-TO-PEAK OUTPUT SWING (V)
VS = 15V TA = 25C
SLEW RATE (V/S)
20
LT1055 GBW
OUTPUT IMPEDANCE ()
24
18 LT1055 12 LT1056
6
VS = 15V f0 = 1MHz FOR GBW -25 25 75 TEMPERATURE (C) 125
LT1055/56 G14
0 0.1
1 FREQUENCY (MHz)
Gain vs Frequency
140 120 100 VS = 15V TA = 25C
GAIN (dB)
GAIN (dB)
80 60 LT1055 40 20 0 -20 LT1056
LT1055 10 GAIN
LT1056
VOLTAGE GAIN (V/mV)
1
10
100
1k 10k 100k 1M 10M 100M FREQUENCY (Hz)
LT1055/56 G16
UW
LT1055/56 G13
AV = 1, CL = 100pF, 0.5s/DIV
LT1055/56 G12
AV = 1, CL = 100pF, 0.2s/DIV
LT1055/56 G11
Slew Rate, Gain Bandwidth vs Temperature
10 GAIN BANDWIDTH PRODUCT (MHz) LT1056 GBW 8 6 4 10 LT1056 SLEW LT1055 SLEW 2
100
Output Impedence vs Frequency
VS = 15V TA = 25C AV = 100
LT1055 10 LT1055 1 LT1056 AV = 10 LT1056
LT1055
LT1056 AV = 1
0
0.1 1 10 100 FREQUENCY (kHz) 1000
LT1055/56 G15
10
Gain, Phase Shift vs Frequency
100 20 1000
Voltage Gain vs Temperature
RL = 2k
PHASE SHIFT (DEGREES)
VS = 15V VO = 10V
PHASE 120 300
RL = 1k 100
140 LT1055 0 VS = 15V TA = 25C -10 1 4 2 FREQUENCY (MHz) 6 8 10 160 LT1056
30
10 -75
25 -25 75 TEMPERATURE (C)
125
LT1055/56 G18
LT1055/56 G17
10556fb
7
LT1055/LT1056 TYPICAL PERFORMANCE CHARACTERISTICS
LT1055 Settling Time
10 OUTPUT VOLTAGE SWING FROM 0V (V) OUTPUT VOLTAGE SWING FROM 0V (V) 2mV 10mV 5 0.5mV
10 10mV 5 2mV
BATTERY VOLTAGE (V)
5mV 0
1mV
5mV 2mV
-5 10mV 1mV 0.5mV VS = 15V TA = 25C -10 0 1 2 3
LT1055/56 G19
SETTLING TIME (S)
Common Mode and Power Supply Rejections vs Temperature
120 VS = 10V TO 17V FOR PSRR VS = 15V, VCM = 10.5V FOR CMRR
POWER SUPPLY REJECTION RATIO (dB)
CMRR, PSRR (dB)
110 PSRR
CMRR (dB)
CMRR 100
90 -25 25 75 TEMPERATURE (C) 125
LT1055/56 G22
Supply Current vs Supply Voltage
8
SHORT-CIRCUIT CURRENT (mA)
SUPPLY CURRENT (mA)
6 LT1056 4 25C LT1055 2 25C TA = - 55C TA = 125C TA = - 55C TA = 125C
OUTPUT VOLTAGE SWING (V)
0
0
10 15 5 SUPPLY VOLTAGE (V)
8
UW
LT1055/56 G25
LT1056 Settling Time
15 14
0.5mV
Common Mode Range vs Temperature
13 12 11 10 -11 -12 -13 -14 VS = 15V -15 50 -50 0 TEMPERATURE (C)
5mV 0 5mV
1mV
VS = 15V TA = 25C
-5 10mV 2mV 1mV 0.5mV
-10
0
1
2
3
LT1055/56 G20
100
LT1055/56 G21
SETTLING TIME (S)
Common Mode Rejection Ratio vs Frequency
120 100 80 60 40 20 0 VS = 15V TA = 25C
140 120 100 80 60 40 20 0
Power Supply Rejection Ratio vs Frequency
TA = 25C
POSITIVE SUPPLY NEGATIVE SUPPLY
10
100
1k 10k 100k FREQUENCY (Hz)
1M
10M
10
100
100k 10k 1k FREQUENCY (Hz)
1M
10M
LT1055/56 G23
LT1055/56 G24
Output Swing vs Load Resistance
15 12 9 6 3 0 -3 -6 -9 -12 TA = -55C 0.3 1 3 LOAD RESISTANCE (k) 10
LT1055/56 G26
Short-Circuit Current vs Time
50 40 30 20 10 0 -10 -20 -30 -40 -50 0 2 1 3 TIME FROM OUTPUT SHORT TO GROUND (MINUTES)
LT1055/56 G27
TA = -55C TA = -25C TA = -125C VS = 15V TA = -25C TA = -125C
TA = - 55C TA = 25C TA = 125C
VS = 15V SINKING TA = 125C TA = 25C TA = - 55C
20
-15 0.1
10556fb
LT1055/LT1056
APPLICATIONS INFORMATION
The LT1055/LT1056 may be inserted directly into LF155A/ LT355A, LF156A/LT356A, OP-15 and OP-16 sockets. Offset nulling will be compatible with these devices with the wiper of the potentiometer tied to the positive supply.
OUTPUT N/C V+ OFFSET TRIM
Offset Nulling
V+ 1 RP 2
- +
V-
5
7 OUT
3
4
LT1055/56 AI1
V- GUARD
IN PU TS
LT1055/56 AI2
LT1055 LT1056
6
No appreciable change in offset voltage drift with temperature will occur when the device is nulled with a potentiometer, RP, ranging from 10k to 200k. The LT1055/LT1056 can also be used in LF351, LF411, AD547, AD611, OPA-111, and TL081 sockets, provided that the nulling cicuitry is removed. Because of the LT1055/ LT1056's low offset voltage, nulling will not be necessary in most applications. Achieving Picoampere/Microvolt Performance In order to realize the picoampere-microvolt level accuracy of the LT1055/LT1056 proper care must be exercised. For example, leakage currents in circuitry external to the op amp can significantly degrade performance. High quality insulation should be used (e.g. TeflonTM, Kel-F); cleaning of all insulating surfaces to remove fluxes and other residues will probably be required. Surface coating may be necessary to provide a moisture barrier in high humidity environments. Board leakage can be minimized by encircling the input circuitry with a guard ring operated at a potential close to that of the inputs: in inverting configurations the guard ring should be tied to ground, in noninverting connnections to the inverting input at pin 2. Guarding both sides of the printed circuit board is required. Bulk leakage reduction depends on the guard ring width.
Teflon is a trademark of Dupont.
U
W
U
U
7 6 5 4
8 1
OFFSET TRIM
2 3
The LT1055/LT1056 has the lowest offset voltage of any JFET input op amp available today. However, the offset voltage and its drift with time and temperature are still not as good as on the best bipolar amplifiers because the transconductance of FETs is considerably lower than that of bipolar transistors. Conversely, this lower transconductance is the main cause of the significantly faster speed performance of FET input op amps. Offset voltage also changes somewhat with temperature cycling. The AM grades show a typical 20V hysteresis (30V on the M grades) when cycled over the -55C to 125C temperature range. Temperature cycling from 0C to 70C has a negligible (less than 10V) hysteresis effect. The offset voltage and drift performance are also affected by packaging. In the plastic N8 package the molding compound is in direct contact with the chip, exerting pressure on the surface. While NPN input transistors are largely unaffected by this pressure, JFET device matching and drift are degraded. Consequently, for best DC performance, as shown in the typical performance distribution plots, the TO-5 H package is recommended. Noise Performance The current noise of the LT1055/LT1056 is practically immeasurable at 1.8fA/Hz. At 25C it is negligible up to 1G of source resistance, RS (compound to the noise of RS). Even at 125C it is negligible to 100M of RS.
10556fb
9
LT1055/LT1056
APPLICATIONS INFORMATION
The voltage noise spectrum is characterized by a low 1/f corner in the 20Hz to 30Hz range, significantly lower than on other competitive JFET input op amps. Of particular interest is the fact that with any JFET IC amplifier, the frequency location of the 1/f corner is proportional to the square root of the internal gate leakage currents and, therefore, noise doubles every 20C. Furthermore, as illustrated in the noise versus chip temperature curves, the 0.1Hz to 10Hz peak-to-peak noise is a strong function of temperature, while wideband noise (f0 = 1kHz) is practically unaffected by temperature. Consequently, for optimum low frequency noise, chip temperature should be minimized. For example, operating an LT1056 at 5V supplies or with a 20C/W case-toambient heat sink reduces 0.1Hz to 10Hz noise from typically 2.5VP-P (15V, free-air) to 1.5VP-P. Similiarly, the noise of an LT1055 will be 1.8VP-P typically because of its lower power dissipation and chip temperature. High Speed Operation Settling time is measured in the test circuit shown. This test configuration has two features which eliminate problems common to settling time measurments: (1) probe
Settling Time Test Circuit
15V 15k 10F SOLID TANTALUM 10pF (TYPICAL)
0.01 DISC
+
-15V 15k 0.01 DISC 2k PULSE GEN INPUT (5V MIN STEP) 50 2W 10F SOLID TANTALUM 15k 0.01 DISC
15V
+ 10F
2k
-15V 15k 0.01 DISC 10F SOLID TANTALUM
10
+
+
SOLID TANTALUM
U
W
+
U
U
capacitance is isolated from the "false summing" node, and (2) it does not require a "flat top" input pulse since the input pulse is merely used to steer current through the diode bridges. For more details, please see Application Note 10. As with most high speed amplifiers, care should be taken with supply decoupling, lead dress and component placement. When the feedback around the op amp is resistive (RF), a pole will be created with RF, the source resistance and capacitance (RS, CS), and the amplifier input capacitance (CIN 4pF). In low closed-loop gain configurations and with RS and RF in the kilohm range, this pole can create excess phase shift and even oscillation. A small capacitor (CF) in parallel with RF eliminates this problem. With RS (CS + CIN) = RFCF, the effect of the feedback pole is completely removed. CF
RF
-
RS CS CIN OUTPUT
+
LT1055/56 AI03
10k
-
LT1055 LT1056 AUT OUTPUT 4.7k 10k 15V
+
AMPLIFIER UNDER TEST 15V 1/2 U440 50
2N3866 2N160 3 -15V 15V OUTPUT TO SCOPE 3 2N3866 2N5160 4.7k -15V
LT1055/56 AI04
HP5082-8210 HEWLETT PACKARD
1/2 U440 100 DC ZERO
= 1N4148
-15V
10556fb
LT1055/LT1056
APPLICATIONS INFORMATION
Phase Reversal Protection Most industry standard JFET input op amps (e.g., LF155/ LF156, LF351, LF411, OP15/16) exhibit phase reversal at the output when the negitive common mode limit at the input is exceeded (i.e., from -12V to -15V with 15V supplies). This can cause lock-up in servo systems. As shown below, the LT1055/LT1056 does not have this problem due to unique phase reversal protection circuitry (Q1 on simplified schematic).
Input Voltage Follower with Input Exceeding the Negative Common Mode Range
15V 2 INPUT 15V SINE WAVE
Output (LF155/LF56, LF441, OP-15/OP-16)
10V/DIV
0.5ms/DIV
LT1055/56 AI06
10V/DIV
0.5ms/DIV
LT1055/56 AI07
10V/DIV
TYPICAL APPLICATIONS
Exponential Voltage-to-Frequency Converter for Music Synthesizers
INPUT 0V TO 10V EXPONENT TRIM 2500* 11.3k* 5 6 3.57k* ZERO TRIM 4 2 500pF POLYSTYRENE 15V 2N3906
500k
4.7k 562* 15V
1.1k
10k*
1k* 1 2 SCALE FACTOR 1V IN OCTAVE OUT *1% METAL FILM RESISTOR PIN NUMBERED TRANSISTORS = CA3096 ARRAY 3
U
3
W
U
U
U
- +
7 6 OUTPUT 2k
LT1055/56 3 4 -15V
LT1055/56 AI05
Output LT1055/LT1056
0.5ms/DIV
LT1055/56 AI08
- +
7 LT1055 6
2N3904 500* SAWTOOTH OUTPUT 1k*
-15V
LM329 10k* 2 4.7k 15V 7 LM301A 3 6 8 1 4 0.01F -15V TEMPERATURE CONTROL LOOP
LT1055/56 TA03
15V 3k 13 1N148 14 15 2.2k 9 8 7 33
- +
For ten additional applications utilizing the LT1055 and LT1056, please see the LTC1043 data sheet and Application Note 3.
10556fb
11
LT1055/LT1056
TYPICAL APPLICATIO S
12-Bit Charge Balance A/D Converter
74C00
249k*
0V TO 10V INPUT 33k LM329 10k 15V COUPLE THERMALLY 6 33k 15V 7 4 -15V 2 CIRCUIT OUTPUT fOUT (A) RATIO fCLK (B)
Fast "No Trims" 12-Bit Multiplying CMOS DAC Amplifier
RFEEDBACK REFERENCE IN TYPICAL 12-BIT CMOS DAC IOUT1
IOUT2
12
U
28k 0.01
14k
0.003F
CLK OUTPUT (B) 10k 6 1N4148 D 10k 1N4148 CLK Q 74C74 Q P CL 2N3904 15V
2
- +
15V 7 LT1055
OUTPUT (A)
3
4 -15V
1N4148
-
LT1001
+
3
1N4148
LT1055/56 TA04
Fast, 16-Bit Current Comparator
HP5082-2810
DELAY = 250ns * = 1% FILM RESISTOR 15V
-
LT1055 OUTPUT
15V INPUT
4.7k
50k* 100k*
2
15V
-
LT1056
7 6 4 3 -15V 2
+
LT1055/56 TA05
+
LT1011
8 7 1 4
3k OUTPUT
3 LT1009 2.5V
+
-
-15V
LT1055/56 TA06
10556fb
LT1055/LT1056
TYPICAL APPLICATIO S
Temperature-to-Frequency Converter
560 15V 2N2222 2N2907 LM329 6.2k* 0.01F POLYSTYRENE 510pF 15V 10k TTL OUTPUT 0kHz TO 1kHz = 0C TO 100C 2N2222 15V 2 10k 6 4.7k 1k* 1k*
510 2V 137*
*1% FILM RESISTOR =1N4148 FREQUENCY LINEARITY = 0.1% FREQUENCY STABILITY = 150ppm/C SETTLING TIME = 1.7s DISTORTION = 0.25% AT 100kHz, 0.07% AT 10zHz 15V 50k 10Hz DISTORTION TRIM -15V
100kHz DISTORTION TRIM 2k 9.09k* 15V 0V TO 10V INPUT 10k* 2
-
LT1056
7 6 2N4391 2N4391 5k* 4 -15V 2N4391 20pF 10k 2.5k* 2
3
+
U
2.7k
500 0C ADJ
2k 100C ADJ
- +
7 LT1055 4 -15V
6.2k* 820*
3
LM134
*1% FILM RESISTOR
LT1055/56 TA07
100kHz Voltage Controlled Oscillator
15V 2
- +
7 6 X1 X2 U1 U2 AD639 COM VR Y1 Y2 5k FREQUENCY TRIM 15V +V CC W Z1 Z2 GT UP -V +15V SINE OUT 2VRMS 0kHs TO 100kHs
LT1056 3 22.1k 1k 68k FINE DISTORTION TRIMS 22M POLYSTYRENE 500pF 10k 68k 15pF -15V 15V 7 LT1056 3 6 4 -15V 22k 4.5k 4 -15V
-15
- +
10k* 2
10k
+
LT1011
8 7 1 4
1k 1k
HP50822810
3
-
0.01F -15V
LM329 4.7k -15V 4.7k 15V
LT1055/56 TA08
10556fb
13
LT1055/LT1056
TYPICAL APPLICATIO S
12-Bit Voltage Output D/A Converter
12-BIT CURRENT OUTPUT D/A CONVERTER (e.g., 6012,565 OR DAC-80) CF 2 0 TO 2 OR 4mA CF = 15pF TO 33pF SETTLING TIME TO 2mV (0.8 LSB) = 1.5s TO 2s
SI PLIFIED SCHE ATIC
NULL 5 7 V+ 7k NULL 1 J5 -INPUT 2 +INPUT 3 J1 J2 Q12 Q11 Q10 20 6 OUTPUT J3 J8 Q1 8k 200 14k 14k 9pF Q3 120A* (160) Q4 120A* (160) 800A* (1000) 400A* (1100) J4 Q2 Q13 Q14 Q5 Q16 J6 300 7.5pF Q9 Q15 J7 7k Q8 Q7
*CURRENTS AS SHOWN FOR LT1055. (X) = CURRENTS FOR LT1056.
LT1055/56 SCHM
14
U
- +
15V 7 LT1056 6 4 -15V
LT1055/56 TA09
3
OUTPUT 0V TO 10V
W
W
3k
50 4 V-
10556fb
LT1055/LT1056
PACKAGE DESCRIPTIO
0.040 (1.016) MAX
SEATING PLANE 0.010 - 0.045* (0.254 - 1.143) 0.016 - 0.021** (0.406 - 0.533)
45TYP 0.028 - 0.034 (0.711 - 0.864)
0.110 - 0.160 (2.794 - 4.064) INSULATING STANDOFF
0.300 - 0.325 (7.620 - 8.255)
0.009 - 0.015 (0.229 - 0.381)
(
+0.035 0.325 -0.015 +0.889 8.255 -0.381
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
U
H Package 8-Lead TO-5 Metal Can (.200 Inch PCD)
(Reference LTC DWG # 05-08-1320)
0.335 - 0.370 (8.509 - 9.398) DIA 0.305 - 0.335 (7.747 - 8.509) 0.050 (1.270) MAX GAUGE PLANE 0.165 - 0.185 (4.191 - 4.699) REFERENCE PLANE 0.500 - 0.750 (12.700 - 19.050) 0.027 - 0.045 (0.686 - 1.143) PIN 1 0.200 (5.080) TYP *LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE AND 0.045" BELOW THE REFERENCE PLANE 0.016 - 0.024 **FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS (0.406 - 0.610)
H8(TO-5) 0.200 PCD 1197
OBSOLETE PACKAGE
N8 Package 8-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
0.400* (10.160) MAX 8 7 6 5
0.255 0.015* (6.477 0.381)
1
2
3
4 0.130 0.005 (3.302 0.127)
0.045 - 0.065 (1.143 - 1.651)
0.065 (1.651) TYP 0.125 (3.175) 0.020 MIN (0.508) MIN 0.018 0.003 (0.457 0.076)
N8 1098
)
0.100 (2.54) BSC
10556fb
15
LT1055/LT1056
TYPICAL APPLICATIO
25mA OUTPUT HEAT SINK OUTPUT TRANSISTORS 100pF
10k
10k INPUT
PACKAGE DESCRIPTIO
0.010 - 0.020 x 45 (0.254 - 0.508) 0.008 - 0.010 (0.203 - 0.254) 0- 8 TYP
0.053 - 0.069 (1.346 - 1.752)
0.014 - 0.019 (0.355 - 0.483) TYP *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE **DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
0.016 - 0.050 (0.406 - 1.270)
RELATED PARTS
PART NUMBER LT1122 LT1792 DESCRIPTION Fast Settling JFET Op Amp Low Noise JFET Op Amp COMMENTS 340ns Settling Time, GBW = 14MHz, SR = 60V/s en = 6nV/Hz Max at f = 1kHz
10556fb
16
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 q FAX: (408) 434-0507
q
U
U
120V Output Precision Op Amp
125V 1F 10k 510 330 1N965 2N5415 2N3440 50k 2 3 1M 2N2222 1N4148 6 4 50k 1M 1N4148 1k 2N2907 2N5415 2N3440 1N965 10k 510 330 27 1k 27 OUTPUT
-
LT1055
7
+
100k
33pF
1F -125V
LT1055/56 TA10
0.189 - 0.197* (4.801 - 5.004) 8 0.004 - 0.010 (0.101 - 0.254) 0.228 - 0.244 (5.791 - 6.197) 0.150 - 0.157** (3.810 - 3.988) 7 6 5
0.050 (1.270) BSC
1
2
3
4
SO8 1298
LT/CPI 0302 1.5K REV B * PRINTED IN USA
www.linear.com
(c) LINEAR TECHNOLOGY CORPORATION 1994

▲Up To Search▲

Price & Availability of LT1056N8

	To Download LT1056N8 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .