OP297FS-REEL ,Dual Low Bias Current Precision Operational AmplifierAPPLICATIONSStrain Gauge and Bridge AmplifiersErrors due to common-mode signals are eliminated by t ..
OP297GP ,Dual Low Bias Current Precision Operational AmplifierCHARACTERISTICSS A ␣␣␣␣OP297E ␣␣␣␣ OP297F ␣␣␣␣␣ OP297GParameterSymbolConditionsMinTypMaxMinTy ..
OP297GPZ , Dual Low Bias Current Precision Operational Amplifier
OP297GS ,Dual Low Bias Current Precision Operational AmplifierCHARACTERISTICSS A ␣␣␣␣OP297E ␣␣␣␣ OP297F ␣␣␣␣␣ OP297GParameterSymbolConditionsMinTypMaxMinTy ..
OP297GS-REEL ,Dual Low Bias Current Precision Operational AmplifierSpecifications subject to change without notice.(@ V = 615 V, T = +258C, unless otherwise noted.)S ..
OP32 ,High-Speed(Avcl => 10) Programmable Micropower Operational AmplifierFEATURES
. Programmable Supply Current ..................... 500nA to 2mA
. Single Supply Opera ..
P401 ,400V 40A 2 SCR Traverse Bridge in a PACE-Pak packageApplications include power supplies, control cir-cuits and battery chargers.Major Ratings and Chara ..
P402 ,600V 40A 2 SCR Traverse Bridge in a PACE-Pak packageBulletin I2776 rev. E 04/99P400 SERIESPASSIVATED ASSEMBLED CIRCUIT ELEMENTS
P403 ,800V 40A 2 SCR Traverse Bridge in a PACE-Pak packageApplications include power supplies, control cir-cuits and battery chargers.Major Ratings and Chara ..
P40-G240-WH , P40-G Series TBU® High-Speed Protectors
P40-G240-WH , P40-G Series TBU® High-Speed Protectors
P40NF10L ,N-CHANNEL 100VELECTRICAL CHARACTERISTICS (TCASE = 25 °C UNLESS OTHERWISE SPECIFIED)OFFSymbol Parameter Test Condi ..
OP297AZ-OP297EZ-OP297FP-OP297FS-OP297FS-REEL-OP297GP-OP297GS-OP297GS-REEL
Dual Low Bias Current Precision Operational Amplifier
8/21/97 4:00 PM
REV.D
Dual Low Bias Current
Precision Operational Amplifier
PIN CONNECTIONS
Plastic Epoxy-DIP (P Suffix)
8-Pin Cerdip (Z Suffix)
8-Pin Narrow Body SOIC (S Suffix)
FEATURES
Precision Performance in Standard SO-8 Pinout
Low Offset Voltage: 50 mV max
Low Offset Voltage Drift: 0.6 mV/8C max
Very Low Bias Current:␣+258C (100 pA max)
␣␣–558C to +1258C (450 pA max)
Very High Open-Loop Gain (2000 V/mV min)
Low Supply Current (Per Amplifier): 625 mA max
Operates From 62 V to 620 V Supplies
High Common-Mode Rejection: 120 dB min
Pin Compatible to LT1013, AD706, AD708, OP221,␣LM158, and MC1458/1558 with Improved Performance
APPLICATIONS
Strain Gauge and Bridge Amplifiers
High Stability Thermocouple Amplifiers
Instrumentation Amplifiers
Photo-Current Monitors
High-Gain Linearity Amplifiers
Long-Term Integrators/Filters
Sample-and-Hold Amplifiers
Peak Detectors
Logarithmic Amplifiers
Battery-Powered Systems
GENERAL DESCRIPTIONThe OP297 is the first dual op amp to pack precision perfor-
mance into the space-saving, industry standard 8-pin SO pack-
age. Its combination of precision with low power and extremely
low input bias current makes the dual OP297 useful in a wide
variety of applications.
Precision performance of the OP297 includes very low offset,
under 50 mV, and low drift, below 0.6 mV/°C. Open-loop gain
exceeds 2000 V/mV insuring high linearity in every application.
Errors due to common-mode signals are eliminated by the
OP297’s common-mode rejection of over 120 dB. The
OP297’s power supply rejection of over 120 dB minimizes
offset voltage changes experienced in battery powered systems.
Supply current of the OP297 is under 625 mA per amplifier and
it can operate with supply voltages as low as –2 V.
The OP297 utilizes a super-beta input stage with bias current
cancellation to maintain picoamp bias currents at all tempera-
tures. This is in contrast to FET input op amps whose bias
currents start in the picoamp range at 25°C, but double for
every 10°C rise in temperature, to reach the nanoamp range
above 85°C. Input bias current of the OP 297 is under 100 pA
at 25°C and is under 450 pA over the military temperature
range.
Combining precision, low power and low bias current, the
OP297 is ideal for a number of applications including instru-
mentation amplifiers, log amplifiers, photodiode preamplifiers
and long-term integrators. For a single device, see the OP97;
for a quad, see the OP497.
Figure 1.Low Bias Current Over TemperatureFigure 2.Very Low OffsetOUT AV+
–IN AOUT B
+IN A–IN B+IN B
TEMPERATURE (°C)
INPUT
CURRENT
(pA)
INPUT OFFSET VOLTAGE (mV)
NUMBER OF UNITS
100–100–80–60–40–20020406080100
8/21/97 4:00 PM
OP297–SPECIFICATIONS
ELECTRICAL CHARACTERISTICSInput Noise Voltage
Input Noise
Input Noise Current Density
Input Resistance
Common-Mode Rejection
Power Supply Rejection
Output Voltage Swing
Supply Current Per Amplifier
Slew Rate
Gain Bandwidth Product
NOTES
1Guaranteed by CMR test.
Specifications subject to change without notice.
ELECTRICAL CHARACTERISTICSInput Bias Current
Large-Signal Voltage Gain
Power Supply Rejection
NOTESGuaranteed by CMR test.
Specifications subject to change without notice.
(@ VS = 615 V, TA = +258C, unless otherwise noted.)
(@ VS = 615 V, –558C £ TA £ +1258C for OP297A, unless otherwise noted.)
8/21/97 4:00 PM
OP297
ELECTRICAL CHARACTERISTICSLarge-Signal Voltage Gain
Input Voltage Range
Common-Mode Rejection
Supply Current Per Amplifier
NOTES
1Guaranteed by CMR test.
Specifications subject to change without notice.
(@ VS = 615 V, –408C £ TA £ +858C for OP297E/F/G, unless otherwise noted.)
Wafer Test LimitsInput Bias Current
Large-Signal Voltage Gain
Input Voltage Range
Common-Mode Rejection
Power Supply
NOTES
1. Guaranteed by CMR test.
Electrical tests are performed at wafer probe to the limits shown. Due to variations in assembly methods and normal yield loss, yield after packaging is not guaranteed
for standard product dice. Consult factory to negotiate specifications based on dice lot qualifications through sample lot assembly and testing.
(@ VS = 615 V, TA = +258C, unless otherwise noted.)
DICE CHARACTERISTICSDimension shown in inches and (mm).
Contact factory for latest dimensions
OUTPUT A
–INPUT A
+INPUT A
OUTPUT B
+VS
0.118 (3.00)
8/21/97 4:00 PM
OP297
CAUTIONESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000V readily
accumulate on the human body and test equipment and can discharge without detection.
ABSOLUTE MAXIMUM RATINGS1Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .–20 V
Input Voltage2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .–20 V
Differential Input Voltage2 . . . . . . . . . . . . . . . . . . . . . . . .40 V
Output Short-Circuit Duration . . . . . . . . . . . . . . . .Indefinite
Storage Temperature Range
Z Package . . . . . . . . . . . . . . . . . . . . . . . . .–65°C to +175°C
P, S Package . . . . . . . . . . . . . . . . . . . . . . .–65°C to +150°C
Operating Temperature Range
OP297A (Z) . . . . . . . . . . . . . . . . . . . . . . .–55°C to +125°C
OP297E, F (Z) . . . . . . . . . . . . . . . . . . . . . .–40°C to +85°C
OP297F, G (P, S) . . . . . . . . . . . . . . . . . . .–40°C to +85°C
Junction Temperature
Z Package . . . . . . . . . . . . . . . . . . . . . . . . .–65°C to +175°C
P, S Package . . . . . . . . . . . . . . . . . . . . . . .–65°C to +150°C
Lead Temperature Range (Soldering, 60 sec) . . . . . . .+300°C
NOTES
1Absolute maximum ratings apply to both DICE and packaged parts, unless
otherwise noted.
2For supply voltages less than –20 V, the absolute maximum input voltage is equal
to the supply voltage.JA is specified for worst case mounting conditions, i.e., qJA is specified for device in
socket for cerdip and P-DIP, packages; qJA is specified for device soldered to printed
circuit board for SO package.
ORDERING GUIDE1NOTES
1Burn-in is available on extended industrial temperature range parts in cerdip, and plastic DIP
packages. For outline information see Package Information section.
2For availability and burn-in information on SO packages, contact your local sales office.
Figure 3.Channel Separation Test Circuit
V1 20Vp-p @ 10Hz
50kW
CHANNEL SEPARATION = 20 log
V2/10000))
8/21/97 4:00 PM
INPUT OFFSET VOLTAGE (mV)
NUMBER OF UNITS
Figure 4.Typical Distribution of Input
Offset Voltage
TEMPERATURE (°C)
INPUT
CURRENT
(pA)
Figure 7.Input Bias, Offset Current
vs. Temperature
SOURCE RESISTANCE (W)
EFFECTIVE OFFSET
GE (1001k10k100k1M10M
Figure 10.Effective Offset Voltage
vs. Source Resistance
INPUT BIAS CURRENT (pA)
NUMBER OF UNITS
Figure 5.Typical Distribution of Input
Bias Current
COMMON-MODE VOLTAGE (VOLTS)
INPUT
CURRENT
(pA)
Figure 8.Input Bias, Offset Current
vs. Common-Mode Voltage
SOURCE RESISTANCE (W)
EFFECTIVE OFFSET
GE DRIFT
°C)
100100M1k10k100k1M10M
Figure 11.Effective TCVOS vs. Source
Resistance
INPUT OFFSET CURRENT (pA)
NUMBER OF UNITS
Figure 6.Typical Distribution of In-
put Offset Current
TIME AFTER POWER APPLIED (MINUTES)
DEVIA
ION FR
OM FINAL
ALUE (321
Figure 9.Input Offset Voltage Warm-
Up Drift
TIME FROM OUTPUT SHORT (MINUTES)234
SHOR
-CIRCUIT
CURRENT
(mA)
Figure 12.Short Circuit Current vs.
Time, Temperature
8/21/97 4:00 PM
OP297
–Typical Performance CharacteristicsSUPPLY VOLTAGE (VOLTS)
SUPPL
CURRENT–5–10–15–20
Figure 13.Total Supply Current vs.
Supply Voltage
GE NOISE DENSITY
(nV/ Hz)
CURRENT
NOISE DENSITY
(fA/ Hz)
FREQUENCY (Hz)
Figure 16.Common-Mode Rejection
vs. Frequency
OUTPUT VOLTAGE (VOLTS)
DIFFERENTIAL
INPUT
GE (10
V/DIV)
Figure 19.Power Supply Rejection
vs. Frequency
FREQUENCY (Hz)
COMMON-MODE REJECTION (dB)
1001101001k10k100k1M
Figure 14.Noise Density vs.
Frequency
SOURCE RESISTANCE (W)
NOISE DENSITY
V/ Hz)
Figure 17.Total Noise Density vs.
Source Resistance
OUTPUT
SWING (V
p-p
LOAD RESISTANCE (W)1001k10k
Figure 20.Open Loop Gain vs. Load
Resistance
WER SUPPL
REJECTION (dB)
FREQUENCY (Hz)
0.11101001k10k100k1M
Figure 15.Open Loop Gain Linearity
LOAD RESISTANCE (kW)1
OPEN-LOOP
GAIN (V/mV)10
Figure 18.Maximum Output Swing
vs. Load Resistance
Figure 21.Maximum Output Swing
vs. Frequency
OUTPUT
SWING (V
p-p
FREQUENCY (Hz)
1001k10k100k
8/21/97 4:00 PM
Figure 24.Open Loop Output
Impedance vs Frequency
APPLICATIONS INFORMATIONExtremely low bias current over the full military temperature
range makes the OP297 attractive for use in sample-and-hold
amplifiers, peak detectors, and log amplifiers that must operate
over a wide temperature range. Balancing input resistances is
not necessary with the OP297 Offset voltage and TCVOS are
degraded only minimally by high source resistance, even when
unbalanced.
The input pins of the OP297 are protected against large differ-
ential voltage by back-to-back diodes and current-limiting resis-
tors. Common-mode voltages at the inputs are not restricted,
and may vary over the full range of the supply voltages used.
The OP297 requires very little operating headroom about the
supply rails, and is specified for operation with supplies as low
as +2 V. Typically, the common-mode range extends to within
one volt of either rail. The output typically swings to within one
volt of the rails when using a 10 kW load.
AC PERFORMANCEThe OP297’S AC characteristics are highly stable over its full
operating temperature range. Unity-gain small-signal response is
shown in Figure 25. Extremely tolerant of capacitive loading on
the output, the OP297 displays excellent response even with
1000 pF loads (Figure 26).
Figure 26.Small-Signal Transient Response
(CLOAD = 1000 pF, AVCL = +1)
Figure 27.Large-Signal Transient Response
(AVCL = +1)
GUARDING AND SHIELDINGTo maintain the extremely high input impedances of the
OP297, care must be taken in circuit board layout and manu-
facturing. Board surfaces must be kept scrupulously clean and
free of moisture. Conformal coating is recommended to provide
FREQUENCY (Hz)
OPEN-LOOP
GAIN (dB)
–401001k10k1001M10M
PHASE SHIFT
(DEG)
VERSHOO
(%)
LOAD CAPACITANCE (pF)100100010000
FREQUENCY (Hz)
OUTPUT
IMPED
ANCE (
0.001101001k10k100k1M
Figure 22.Open Loop Gain,
Phase vs. Frequency
Figure 23.Small Signal Overshoot
vs. Capacitance Load
8/21/97 4:00 PM
OP297a humidity barrier. Even a clean PC board can have 100 pA of
leakage currents between adjacent traces, so guard rings should
be used around the inputs. Guard traces are operated at a volt-
age close to that on the inputs, as shown in Figure 28, so that
leakage currents become minimal. In noninverting applications,
the guard ring should be connected to the common-mode volt-
age at the inverting input. In inverting applications, both inputs
remain at ground, so the guard trace should be grounded. Guard
traces should be on both sides of the circuit board.
OPEN-LOOP GAIN LINEARITYThe OP297 has both an extremely high gain of 2000 V/mV
minimum and constant gain linearity. This enhances the preci-
sion of the OP297 and provides for very high accuracy in high
closed loop gain applications. Figure 29 illustrates the typical
open-loop gain linearity of the OP297 over the military tempera-
ture range.
DIFFERENTIAL
INPUT
GE (10
V/DIV)
APPLICATIONS
PRECISION ABSOLUTE VALUE AMPLIFIER
The circuit of Figure 30 is a precision absolute value amplifier
with an input impedance of 30 MW. The high gain and low
TCVOS of the OP297 insure accurate operation with microvolt
input signals. In this circuit, the input always appears as a
common-mode signal to the op amps. The CMR of the OP297
exceeds 120 dB, yielding an error of less than 2 ppm.
–15VVIN
+15V
Figure 30.Precision Absolute Value Amplifier
PRECISION CURRENT PUMPMaximum output current of the precision current pump shown
in Figure 31 is –10 mA. Voltage compliance is –10 V with15 V supplies. Output impedance of the current transmitter
UNITY-GAIN FOLLOWER
INVERTING AMPLIFIER
NONINVERTING AMPLIFIER
MINI-DIP
BOTTOM VIEW8
Figure 28.Guard Ring Layout and Connections
