LF155/LF156/LF256/LF257/LF355/LF356/LF357
JFET Input Operational Amplifiers
General Description
These are the first monolithic JFET input operational ampli-
fiers to incorporate well matched, high voltage JFETs on the
same chip with standard bipolar transistors (BI-FET™Tech-
nology). These amplifiers feature low input bias and offset
currents/low offset voltage and offset voltage drift, coupled
with offset adjust which does not degrade drift or
common-mode rejection. The devices are also designed for
high slew rate, wide bandwidth, extremely fast settling time,
low voltage and current noise and a low 1/f noise corner.
Features
Advantages
nReplace expensive hybrid and module FET op amps
nRugged JFETs allow blow-out free handling compared
with MOSFET input devices
nExcellent for low noise applications using either high or
low source impedance—very low 1/f corner
nOffset adjust does not degrade drift or common-mode
rejection as in most monolithic amplifiers
nNew output stage allows use of large capacitive loads
(5,000 pF) without stability problems
nInternal compensation and large differential input voltage
capability
Applications
nPrecision high speed integrators
nFast D/A and A/D converters
nHigh impedance buffers
nWideband, low noise, low drift amplifiers
nLogarithmic amplifiers
nPhotocell amplifiers
nSample and Hold circuits
Common Features
nLow input bias current: 30pA
nLow Input Offset Current: 3pA
nHigh input impedance: 10
12
Ω
nLow input noise current:
nHigh common-mode rejection ratio: 100 dB
nLarge dc voltage gain: 106 dB
Uncommon Features
LF155/
LF355 LF156/
LF256/
LF356
LF257/
LF357
(A
V
=5)
Units
jExtremely
fast settling
time to
0.01%
4 1.5 1.5 µs
jFast slew
rate 5 12 50 V/µs
jWide gain
bandwidth 2.5 5 20 MHz
jLow input
noise
voltage
20 12 12
Simplified Schematic
00564601
*3pF in LF357 series.
BI-FET™, BI-FET II™are trademarks of National Semiconductor Corporation.
December 2001
LF155/LF156/LF256/LF257/LF355/LF356/LF357 JFET Input Operational Amplifiers
© 2001 National Semiconductor Corporation DS005646 www.national.com
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, contact the National Semiconductor Sales Office/Distributors for
availability and specifications.
LF155/6 LF256/7/LF356B LF355/6/7
Supply Voltage ±22V ±22V ±18V
Differential Input Voltage ±40V ±40V ±30V
Input Voltage Range (Note 2) ±20V ±20V ±16V
Output Short Circuit Duration Continuous Continuous Continuous
T
JMAX
H-Package 150˚C 115˚C 115˚C
N-Package 100˚C 100˚C
M-Package 100˚C 100˚C
Power Dissipation at T
A
= 25˚C (Notes
1, 8)
H-Package (Still Air) 560 mW 400 mW 400 mW
H-Package (400 LF/Min Air Flow) 1200 mW 1000 mW 1000 mW
N-Package 670 mW 670 mW
M-Package 380 mW 380 mW
Thermal Resistance (Typical) θ
JA
H-Package (Still Air) 160˚C/W 160˚C/W 160˚C/W
H-Package (400 LF/Min Air Flow) 65˚C/W 65˚C/W 65˚C/W
N-Package 130˚C/W 130˚C/W
M-Package 195˚C/W 195˚C/W
(Typical) θ
JC
H-Package 23˚C/W 23˚C/W 23˚C/W
Storage Temperature Range −65˚C to +150˚C −65˚C to +150˚C −65˚C to +150˚C
Soldering Information (Lead Temp.)
Metal Can Package
Soldering (10 sec.) 300˚C 300˚C 300˚C
Dual-In-Line Package
Soldering (10 sec.) 260˚C 260˚C 260˚C
Small Outline Package
Vapor Phase (60 sec.) 215˚C 215˚C
Infrared (15 sec.) 220˚C 220˚C
See AN-450 “Surface Mounting Methods and Their Effect on Product Reliability” for other methods of
soldering surface mount devices.
ESD tolerance
(100 pF discharged through 1.5kΩ) 1000V 1000V 1000V
DC Electrical Characteristics
(Note 3)
Symbol Parameter Conditions LF155/6 LF256/7
LF356B LF355/6/7 Units
Min Typ Max Min Typ Max Min Typ Max
V
OS
Input Offset Voltage R
S
=50Ω,T
A
=25˚C 3 5 3 5 3 10 mV
Over Temperature 7 6.5 13 mV
∆V
OS
/∆T Average TC of Input
Offset Voltage R
S
=50Ω5 5 5 µV/˚C
∆TC/∆V
OS
Change in Average TC
with V
OS
Adjust R
S
=50Ω, (Note 4) 0.5 0.5 0.5 µV/˚C
per mV
I
OS
Input Offset Current T
J
=25˚C, (Notes 3, 5) 3 20 3 20 3 50 pA
T
J
≤T
HIGH
20 1 2 nA
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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DC Electrical Characteristics (Continued)
(Note 3)
Symbol Parameter Conditions LF155/6 LF256/7
LF356B LF355/6/7 Units
Min Typ Max Min Typ Max Min Typ Max
I
B
Input Bias Current T
J
=25˚C, (Notes 3, 5) 30 100 30 100 30 200 pA
T
J
≤T
HIGH
50 5 8 nA
R
IN
Input Resistance T
J
=25˚C 10
12
10
12
10
12
Ω
A
VOL
Large Signal Voltage
Gain V
S
=±15V, T
A
=25˚C 50 200 50 200 25 200 V/mV
V
O
=±10V, R
L
=2k
Over Temperature 25 25 15 V/mV
V
O
Output Voltage Swing V
S
=±15V, R
L
=10k ±12 ±13 ±12 ±13 ±12 ±13 V
V
S
=±15V, R
L
=2k ±10 ±12 ±10 ±12 ±10 ±12 V
V
CM
Input Common-Mode
Voltage Range V
S
=±15V ±11 +15.1 ±11 ±15.1 +10 +15.1 V
−12 −12 −12 V
CMRR Common-Mode
Rejection Ratio 85 100 85 100 80 100 dB
PSRR Supply Voltage
Rejection Ratio (Note 6) 85 100 85 100 80 100 dB
DC Electrical Characteristics
T
A
=T
J
= 25˚C, V
S
=±15V
Parameter LF155 LF355 LF156/256/257/356B LF356 LF357 Units
Typ Max Typ Max Typ Max Typ Max Typ Max
Supply
Current 2424 5 7 510510mA
AC Electrical Characteristics
T
A
=T
J
= 25˚C, V
S
=±15V
Symbol Parameter Conditions LF155/355 LF156/256/
356B LF156/256/356/
LF356B LF257/357 Units
Typ Min Typ Typ
SR Slew Rate LF155/6:
A
V
=1, 5 7.5 12 V/µs
LF357: A
V
=5 50 V/µs
GBW Gain Bandwidth Product 2.5 5 20 MHz
t
s
Settling Time to 0.01% (Note 7) 4 1.5 1.5 µs
e
n
Equivalent Input Noise
Voltage R
S
=100Ω
f=100 Hz 25 15 15
f=1000 Hz 20 12 12
i
n
Equivalent Input Current
Noise f=100 Hz 0.01 0.01 0.01
f=1000 Hz 0.01 0.01 0.01
C
IN
Input Capacitance 3 3 3 pF
Notes for Electrical Characteristics
Note 1: The maximum power dissipation for these devices must be derated at elevated temperatures and is dictated by TJMAX,θJA, and the ambient temperature,
TA. The maximum available power dissipation at any temperature is PD=(TJMAX−TA)/θJA or the 25˚C PdMAX, whichever is less.
Note 2: Unless otherwise specified the absolute maximum negative input voltage is equal to the negative power supply voltage.
Note 3: Unless otherwise stated, these test conditions apply:
LF155/LF156/LF256/LF257/LF355/LF356/LF357
www.national.com3
Notes for Electrical Characteristics (Continued)
LF155/156 LF256/257 LF356B LF355/6/7
Supply Voltage, V
S
±15V ≤V
S
≤±20V ±15V ≤V
S
≤±20V ±15V ≤V
S
±20V V
S
=±15V
T
A
−55˚C ≤T
A
≤+125˚C −25˚C ≤T
A
≤+85˚C 0˚C ≤T
A
≤+70˚C 0˚C ≤T
A
≤+70˚C
T
HIGH
+125˚C +85˚C +70˚C +70˚C
and VOS,I
Band IOS are measured at VCM =0.
Note 4: The Temperature Coefficient of the adjusted input offset voltage changes only a small amount (0.5µV/˚C typically) for each mV of adjustment from its original
unadjusted value. Common-mode rejection and open loop voltage gain are also unaffected by offset adjustment.
Note 5: The input bias currents are junction leakage currents which approximately double for every 10˚C increase in the junction temperature, TJ. Due to limited
production test time, the input bias currents measured are correlated to junction temperature. In normal operation the junction temperature rises above the ambient
temperature as a result of internal power dissipation, Pd. TJ=T
A+θ
JA Pd where θJA is the thermal resistance from junction to ambient. Use of a heat sink is
recommended if input bias current is to be kept to a minimum.
Note 6: Supply Voltage Rejection is measured for both supply magnitudes increasing or decreasing simultaneously, in accordance with common practice.
Note 7: Settling time is defined here, for a unity gain inverter connection using 2 kΩresistors for the LF155/6. It is the time required for the error voltage (the voltage
at the inverting input pin on the amplifier) to settle to within 0.01% of its final value from the time a 10V step input is applied to the inverter. For the LF357, AV= −5,
the feedback resistor from output to input is 2kΩand the output step is 10V (See Settling Time Test Circuit).
Note 8: Max. Power Dissipation is defined by the package characteristics. Operating the part near the Max. Power Dissipation may cause the part to operate outside
guaranteed limits.
Typical DC Performance Characteristics Curves are for LF155 and LF156 unless otherwise
specified.
Input Bias Current Input Bias Current
00564637 00564638
Input Bias Current Voltage Swing
00564639 00564640
LF155/LF156/LF256/LF257/LF355/LF356/LF357
www.national.com 4
Typical DC Performance Characteristics Curves are for LF155 and LF156 unless otherwise
specified. (Continued)
Supply Current Supply Current
00564641 00564642
Negative Current Limit Positive Current Limit
00564643 00564644
Positive Common-Mode
Input Voltage Limit Negative Common-Mode
Input Voltage Limit
00564645 00564646
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical DC Performance Characteristics Curves are for LF155 and LF156 unless otherwise
specified. (Continued)
Open Loop Voltage Gain Output Voltage Swing
00564647 00564648
Typical AC Performance Characteristics
Gain Bandwidth Gain Bandwidth
00564649 00564650
Normalized Slew Rate Output Impedance
00564651 00564652
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical AC Performance Characteristics (Continued)
Output Impedance LF155 Small Signal Pulse Response, A
V
=+1
00564653
00564605
LF156 Small Signal Pulse Response, A
V
= +1 LF155 Large Signal Pulse Response, A
V
=+1
00564606 00564608
LF156 Large Signal Puls
Response, A
V
= +1 Inverter Settling Time
00564609
00564655
LF155/LF156/LF256/LF257/LF355/LF356/LF357
www.national.com7
Typical AC Performance Characteristics (Continued)
Inverter Settling Time Open Loop Frequency Response
00564656 00564657
Bode Plot Bode Plot
00564658 00564659
Bode Plot Common-Mode Rejection Ratio
00564660 00564661
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical AC Performance Characteristics (Continued)
Power Supply Rejection Ratio Power Supply Rejection Ratio
00564662 00564663
Undistorted Output Voltage Swing Equivalent Input Noise Voltage
00564664
00564665
Equivalent Input Noise
Voltage (Expanded Scale)
00564666
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Detailed Schematic
00564613
*C = 3pF in LF357 series.
Connection Diagrams (Top Views)
Metal Can Package (H)
00564614
Order Number LF155H, LF156H, LF256H, LF257H,
LF356BH, LF356H, or LF357H
See NS Package Number H08C
*Available per JM38510/11401 or JM38510/11402
Dual-In-Line Package (M and N)
00564629
Order Number LF356M, LF356MX, LF355N, or LF356N
See NS Package Number M08A or N08E
Application Hints
These are op amps with JFET input devices. These JFETs
have large reverse breakdown voltages from gate to source
and drain eliminating the need for clamps across the inputs.
Therefore large differential input voltages can easily be ac-
commodated without a large increase in input current. The
maximum differential input voltage is independent of the
supply voltages. However, neither of the input voltages
should be allowed to exceed the negative supply as this will
cause large currents to flow which can result in a destroyed
unit.
Exceeding the negative common-mode limit on either input
will force the output to a high state, potentially causing a
LF155/LF156/LF256/LF257/LF355/LF356/LF357
www.national.com 10
Application Hints (Continued)
reversal of phase to the output. Exceeding the negative
common-mode limit on both inputs will force the amplifier
output to a high state. In neither case does a latch occur
since raising the input back within the common-mode range
again puts the input stage and thus the amplifier in a normal
operating mode.
Exceeding the positive common-mode limit on a single input
will not change the phase of the output however, if both
inputs exceed the limit, the output of the amplifier will be
forced to a high state.
These amplifiers will operate with the common-mode input
voltage equal to the positive supply. In fact, the
common-mode voltage can exceed the positive supply by
approximately 100 mV independent of supply voltage and
over the full operating temperature range. The positive sup-
ply can therefore be used as a reference on an input as, for
example, in a supply current monitor and/or limiter.
Precautions should be taken to ensure that the power supply
for the integrated circuit never becomes reversed in polarity
or that the unit is not inadvertently installed backwards in a
socket as an unlimited current surge through the resulting
forward diode within the IC could cause fusing of the internal
conductors and result in a destroyed unit.
All of the bias currents in these amplifiers are set by FET
current sources. The drain currents for the amplifiers are
therefore essentially independent of supply voltage.
As with most amplifiers, care should be taken with lead
dress, component placement and supply decoupling in order
to ensure stability. For example, resistors from the output to
an input should be placed with the body close to the input to
minimize “pickup” and maximize the frequency of the feed-
back pole by minimizing the capacitance from the input to
ground.
A feedback pole is created when the feedback around any
amplifier is resistive. The parallel resistance and capacitance
from the input of the device (usually the inverting input) toAC
ground set the frequency of the pole. In many instances the
frequency of this pole is much greater than the expected 3dB
frequency of the closed loop gain and consequently there is
negligible effect on stability margin. However, if the feedback
pole is less than approximately six times the expected 3 dB
frequency a lead capacitor should be placed from the output
to the input of the op amp. The value of the added capacitor
should be such that the RC time constant of this capacitor
and the resistance it parallels is greater than or equal to the
original feedback pole time constant.
Typical Circuit Connections
V
OS
Adjustment
00564667
•V
OS
is adjusted with a 25k potentiometer
•The potentiometer wiper is connected to V
+
•For potentiometers with temperature coefficient of 100
ppm/˚C or less the additional drift with adjust is ≈0.5µV/
˚C/mV of adjustment
•Typical overall drift: 5µV/˚C ±(0.5µV/˚C/mV of adj.)
Driving Capacitive Loads
00564668
*LF155/6 R = 5k
LF357 R = 1.25k
Due to a unique output stage design, these amplifiers
have the ability to drive large capacitive loads and still
maintain stability. C
L(MAX)
.0.01µF.
Overshoot ≤20%
Settling time (t
s
).5µs
LF357. A Large Power BW Amplifier
00564615
For distortion ≤1% and a 20 Vp-p VOUT swing, power bandwidth is:
500kHz.
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical Applications
Settling Time Test Circuit
00564616
•Settling time is tested with the LF155/6 connected as unity gain inverter and LF357 connected for A
V
=−5
•FET used to isolate the probe capacitance
•Output = 10V step
•A
V
= −5 for LF357
Large Signal Inverter Output, V
OUT
(from Settling Time Circuit)
LF355
00564617
LF356
00564618
LF357
00564619
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical Applications (Continued)
Low Drift Adjustable Voltage Reference
00564620
•∆V
OUT
/∆T=±
0.002%/˚C
•All resistors and potentiometers should be wire-wound
•P1: drift adjust
•P2: V
OUT
adjust
•Use LF155 for
jLow I
B
jLow drift
jLow supply current
Fast Logarithmic Converter
00564621
•Dynamic range: 100µA ≤I
i
≤1mA (5 decades), |V
O
| = 1V/decade
•Transient response: 3µs for ∆I
i
= 1 decade
•C1, C2, R2, R3: added dynamic compensation
•V
OS
adjust the LF156 to minimize quiescent error
•R
T
: Tel Labs type Q81 + 0.3%/˚C
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical Applications (Continued)
Precision Current Monitor
00564631
•V
O
= 5 R1/R2 (V/mA of I
S
)
•R1, R2, R3: 0.1% resistors
•Use LF155 for
jCommon-mode range to supply range
jLow I
B
jLow V
OS
jLow Supply Current
8-Bit D/A Converter with Symmetrical Offset Binary Operation
00564632
•R1, R2 should be matched within ±0.05%
•Full-scale response time: 3µs
E
O
B1 B2 B3 B4 B5 B6 B7 B8 Comments
+9.920 11111111 Positive Full-Scale
+0.040 10000000 (+)Zero-Scale
−0.040 01111111 (−)Zero-Scale
−9.920 00000000Negative Full-Scale
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical Applications (Continued)
Wide BW Low Noise, Low Drift Amplifier
00564670
•Parasitic input capacitance C1 .(3pF for LF155, LF156 and LF357 plus any additional layout capacitance) interacts with
feedback elements and creates undesirable high frequency pole. To compensate add C2 such that: R2 C2 .R1 C1.
Boosting the LF156 with a Current Amplifier
00564673
•I
OUT(MAX)
.150mA (will drive R
L
≥100Ω)
•No additional phase shift added by the current amplifier
LF155/LF156/LF256/LF257/LF355/LF356/LF357
www.national.com15
Typical Applications (Continued)
3 Decades VCO
00564624
R1, R4 matched. Linearity 0.1% over 2 decades.
Isolating Large Capacitive Loads
00564622
•Overshoot 6%
•t
s
10µs
•When driving large C
L
, the V
OUT
slew rate determined by C
L
and I
OUT(MAX)
:
LF155/LF156/LF256/LF257/LF355/LF356/LF357
www.national.com 16
Typical Applications (Continued)
Low Drift Peak Detector
00564623
•By adding D1 and R
f
,V
D1
=0 during hold mode. Leakage of D2 provided by feedback path through R
f
.
•Leakage of circuit is essentially I
b
(LF155, LF156) plus capacitor leakage of Cp.
•Diode D3 clamps V
OUT
(A1) to V
IN
−V
D3
to improve speed and to limit reverse bias of D2.
•Maximum input frequency should be <<
1
⁄
2
πR
f
C
D2
where C
D2
is the shunt capacitance of D2.
Non-Inverting Unity Gain Operation for LF157
00564675
Inverting Unity Gain for LF157
00564625
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical Applications (Continued)
High Impedance, Low Drift Instrumentation Amplifier
00564626
•System V
OS
adjusted via A2 V
OS
adjust
•Trim R3 to boost up CMRR to 120 dB. Instrumentation amplifier resistor array recommended for best accuracy and lowest drift
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical Applications (Continued)
Fast Sample and Hold
00564633
•Both amplifiers (A1, A2) have feedback loops individually closed with stable responses (overshoot negligible)
•Acquisition time T
A
, estimated by:
•LF156 develops full S
r
output capability for V
IN
≥1V
•Addition of SW2 improves accuracy by putting the voltage drop across SW1 inside the feedback loop
•Overall accuracy of system determined by the accuracy of both amplifiers, A1 and A2
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical Applications (Continued)
High Accuracy Sample and Hold
00564627
•By closing the loop through A2, the V
OUT
accuracy will be determined uniquely by A1.
No V
OS
adjust required for A2.
•T
A
can be estimated by same considerations as previously but, because of the added
propagation delay in the feedback loop (A2) the overshoot is not negligible.
•Overall system slower than fast sample and hold
•R1, C
C
: additional compensation
•Use LF156 for
jFast settling time
jLow V
OS
High Q Band Pass Filter
00564628
•By adding positive feedback (R2)
•Q increases to 40
•f
BP
= 100 kHz
•Clean layout recommended
•Response to a 1Vp-p tone burst: 300µs
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Typical Applications (Continued)
High Q Notch Filter
00564634
•2R1=R=10MΩ
2C = C1 = 300pF
•Capacitors should be matched to obtain high Q
•f
NOTCH
= 120 Hz, notch = −55 dB, Q >100
•Use LF155 for
jLow I
B
jLow supply current
LF155/LF156/LF256/LF257/LF355/LF356/LF357
www.national.com21
Physical Dimensions inches (millimeters) unless otherwise noted
Metal Can Package (H)
Order Number LF155H, LF156H, LF256H, LF257H, LF356BH, LF356H or LF357H
NS Package Number H08C
Small Outline Package (M)
Order Number LF356M or LF356MX
NS Package Number M08A
LF155/LF156/LF256/LF257/LF355/LF356/LF357
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Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
Molded Dual-In-Line Package (N)
Order Number LF356N
NS Package Number N08E
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NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and
whose failure to perform when properly used in
accordance with instructions for use provided in the
labeling, can be reasonably expected to result in a
significant injury to the user.
2. A critical component is any component of a life
support device or system whose failure to perform
can be reasonably expected to cause the failure of
the life support device or system, or to affect its
safety or effectiveness.
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Corporation
Americas
Email: support@nsc.com
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Email: europe.support@nsc.com
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Fax: 81-3-5639-7507
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LF155/LF156/LF256/LF257/LF355/LF356/LF357 JFET Input Operational Amplifiers
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.
National P/N LF356 - JFET Input Operational Amplifiers
See Audio Products
Products > Analog - Amplifiers > Operational Amplifiers > General Purpose > LF356
LF356 Product Folder
JFET Input Operational Amplifiers
Generic P/N 356
General
Description Features Datasheet Package
& Models Samples
& Pricing Design
Tools Application
Notes
Parametric Table Parametric Table
Channels (Channels) 1
Input Output Type Vcm to V+, Not R-R
Out
Bandwidth, typ (MHz) 5, 12
Slew Rate, typ (Volts/usec) 12
Supply Current per Channel, typ (mA) 5
Minimum Supply Voltage (Volt) 10
Maximum Supply Voltage (Volt) 36, 44
Offset Voltage, Max (mV) 10, 5
Input Bias Current, Temp Max (nA) 8, 5
Output Current, typ (mA) 25
Voltage Noise, typ (nV/Hz) 12
Shut down No
Special Features Undefined
Datasheet
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LF356
M
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National P/N LF356 - JFET Input Operational Amplifiers
LF356MX SOIC
NARROW 8MSL Full
production LF356.MOD N/A
Buy Now
1K+ $0.2990 reel
of
2500
[logo]¢2¢T
LF356
M
LF356N MDIP 8MSL Full
production LF356.MOD N/A
Buy Now
1K+ $0.3070 rail
of
40
[logo]¢U¢Z¢2¢T
LF
356N
LF356BH TO-5 8MSL Full
production LF356.MOD N/A
Buy Now
1K+ $1.6800 box
of
500
[logo]¢Z¢2¢T
LF356BH
LF356H TO-5 8MSL Full
production LF356.MOD N/A
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1K+ $1.1800 box
of
500
[logo]¢Z¢2¢T
LF356H
LF356
MDC Die Full
production LF356.MOD N/A
Samples
tray
of
N/A -
LF356
MWC Wafer Full
production LF356.MOD N/A
wafer
jar
of
N/A
-
General Description
These are the first monolithic JFET input operational amplifiers to incorporate well matched, high voltage
JFETs on the same chip with standard bipolar transistors (BI-FET™ Technology). These amplifiers feature low
input bias and offset currents/low offset voltage and offset voltage drift, coupled with offset adjust which
does not degrade drift or common-mode rejection. The devices are also designed for high slew rate, wide
bandwidth, extremely fast settling time, low voltage and current noise and a low 1/f noise corner.
Features
Advantages
● Replace expensive hybrid and module FET op amps
● Rugged JFETs allow blow-out free handling compared with MOSFET input devices
● Excellent for low noise applications using either high or low source impedance-very low 1/f corner
● Offset adjust does not degrade drift or common-mode rejection as in most monolithic amplifiers
● New output stage allows use of large capacitive loads (5,000 pF) without stability problems
● Internal compensation and large differential input voltage capability
Applications
● Precision high speed integrators
● Fast D/A and A/D converters
● High impedance buffers
● Wideband, low noise, low drift amplifiers
● Logarithmic amplifiers
● Photocell amplifiers
● Sample and Hold circuits
Design Tools
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National P/N LF356 - JFET Input Operational Amplifiers
Title Size in Kbytes Date View Online Download Receive via Email
Amplifiers Selection Guide
software for Windows 7 Kbytes 12-Jun-2002 View
If you have trouble printing or viewing PDF file(s), see Printing Problems.
Application Notes
Title Size in Kbytes Date View Online Download Receive via
Email
AN-447: Protection Schemes for
BI-FET Amplifiers and Switches 76 Kbytes 4-Nov-95 View Online Download Receive via Email
AN-292: Application Note 292
Applications of the LM3524 Pulse-
Width-Modulator 239 Kbytes 1-May-98 View Online Download Receive via Email
AN-263: Sine Wave Generation
Techniques 223 Kbytes 4-Nov-95 View Online Download Receive via Email
AN-272: Op Amp Booster
Designs 171 Kbytes 9-Apr-96 View Online Download Receive via Email
LB-42: Get Fast Stable Response
From Improved Unity-Gain
Followers 83 Kbytes 28-Jun-96 View Online Download Receive via Email
AN-275: CMOS D/A Converters
Match Most Microprocessors 124 Kbytes 4-Nov-95 View Online Download Receive via Email
AN-293: Control Applications of
CMOS DACs 178 Kbytes 4-Nov-95 View Online Download Receive via Email
AN-253: LH0024 and LH0032
High Speed Op Amp Applications 276 Kbytes 4-Nov-95 View Online Download Receive via Email
AN-258: Data Acquisition Using
the ADC0816 and ADC0817 8-Bit
A/D Converter with On-Chip 16
Channel Multiplexer
388 Kbytes 4-Nov-95 View Online Download Receive via Email
AN-260: A 20-Bit (1 ppm) Linear
Slope-Integrating A/D Converter 148 Kbytes 4-Nov-95 View Online Download Receive via Email
AN-294: Special Sample and Hold
Techniques 133 Kbytes 4-Nov-95 View Online Download Receive via Email
AN-311: Application Note 311
Theory and Applications of
Logarithmic Amplifiers 206 Kbytes 24-Feb-99 View Online Download Receive via Email
AN-480: A 40 MHz Programmable
Video Op Amp 181 Kbytes 4-Nov-95 View Online Download Receive via Email
If you have trouble printing or viewing PDF file(s), see Printing Problems.
[Information as of 5-Aug-2002]
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