BB INA157UA

®
INA157
INA
157
For most current data sheet and other product
information, visit www.burr-brown.com
High-Speed, Precision
DIFFERENCE AMPLIFIER
FEATURES
APPLICATIONS
● DESIGNED FOR LOW COST
● DIFFERENTIAL INPUT AMPLIFIER
● LOW OFFSET VOLTAGE: ±500µV max
● LOW OFFSET DRIFT: ±2µV/°C
● INSTRUMENTATION AMPLIFIER
BUILDING BLOCK
● G = 1/2 AMPLIFIER
● LOW GAIN ERROR: ±0.05% max
● WIDE BANDWIDTH: 3MHz
● G = 2 AMPLIFIER
● DIFFERENTIAL CURRENT RECEIVER
● HIGH SLEW RATE: 14V/µs
● FAST SETTLING TIME: 3µs to 0.01%
● VOLTAGE-CONTROLLED CURRENT SOURCE
● GROUND LOOP ELIMINATOR
● WIDE SUPPLY RANGE: ±4V to ±18V
● LOW QUIESCENT CURRENT: 2.4mA
● CURRENT SHUNT MONITOR
● SO-8 SURFACE-MOUNT PACKAGE
DESCRIPTION
V+
The INA157 is a high slew rate, G = 1/2 or G = 2
difference amplifier consisting of a precision op amp
with a precision resistor network. The on-chip resistors are laser trimmed for accurate gain and high
common-mode rejection. Excellent TCR tracking of
the resistors maintains gain accuracy and commonmode rejection over temperature. The input commonmode voltage range extends beyond the positive and
negative supply rails. It operates on ±4V to ±18V
supplies.
The difference amplifier is the foundation of many
commonly used circuits. The INA157 provides this
circuit function without using an expensive precision
resistor network. The INA157 is available in a SO-8
surface-mount package and is specified for operation
over the extended industrial temperature range, –40°C
to +85°C.
7
–In
2
12kΩ
6kΩ
5
6
+In
3
12kΩ
6kΩ
1
Sense
Output
Ref
4
V–
International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111
Twx: 910-952-1111 • Internet: http://www.burr-brown.com/ • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
©1999 Burr-Brown Corporation
PDS-1483B
Printed in U.S.A. March, 1999
SPECIFICATIONS: VS = ±15V
At TA = +25°C, VS = ±15V, RL = 2kΩ connected to ground, and reference pin connected to ground, unless otherwise noted.
INA157U
PARAMETER
CONDITIONS
VOLTAGE(1)
OFFSET
Initial(1)
vs Temperature
vs Power Supply
vs Time
MIN
OUTPUT VOLTAGE NOISE(3)
f = 0.1Hz to 10Hz
f = 1kHz
GAIN
Initial
Error
vs Temperature
Nonlinearity
VS = ±4V to ±18V
VCM
VO = 0V
3(V+)–7.5
VO = 0V
3(V–)+7.5
= –37.5V to 37.5V, RS = 0Ω
86
✽
✽
80
3(V+)–6
3(V–)+3
96
1.3
26
0.5
±0.01
±1
±0.0001
VO = –10V to +10V
TEMPERATURE RANGE
Specified
Operation
Storage
Thermal Resistance, ΘJA
SO-8 Surface-Mount
±500
±20
±60
TYP
MAX
UNITS
✽
✽
✽
✽
±1000
✽
✽
µV
µV/°C
µV/V
µV/mo
✽
✽
kΩ
kΩ
✽
✽
✽
V
V
dB
✽
✽
µVp-p
nV/√Hz
RTO
OUTPUT
Voltage, Positive
Negative
Current Limit, Continuous to Common
Capacitive Load (stable operation)
POWER SUPPLY
Rated Voltage
Operating Voltage Range
Quiescent Current
±100
±2
±5
0.25
MIN
24
18
VO = –10V to +10V
FREQUENCY RESPONSE
Small-Signal Bandwidth
Slew Rate
Settling Time: 0.1%
0.01%
Overload Recovery Time
MAX
RTO
INPUT IMPEDANCE(2)
Differential
Common-Mode
INPUT VOLTAGE RANGE
Common-Mode Voltage Range
Positive
Negative
Common-Mode Rejection Ratio
INA157UA
TYP
(V+)–2
(V–)+2
–3dB
✽
✽
✽
✽
±0.05
±10
±0.001
✽
✽
(V+)–1.8
(V–)+1.6
±60
500
4
14
2
3
3
10V Step, CL = 100pF
10V Step, CL = 100pF
50% Overdrive
±15
±4
±2.4
IO = 0mA
–40
–55
–55
150
±0.1
✽
±0.002
✽
✽
✽
✽
V
V
mA
pF
✽
✽
✽
✽
✽
MHz
V/µs
µs
µs
µs
✽
±18
±2.9
✽
+85
+125
+125
✽
✽
✽
V/V
%
ppm/°C
% of FS
✽
✽
✽
✽
V
V
mA
✽
✽
✽
°C
°C
°C
°C/W
✽Specifications the same as INA157U.
NOTES: (1) Includes effects of amplifier’s input bias and offset currents. (2) Internal resistors are ratio matched but have ±20% absolute value. (3) Includes effects
of amplifier’s input current noise and thermal noise contribution of resistor network.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes
no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change
without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant
any BURR-BROWN product for use in life support devices and/or systems.
®
INA157
2
ABSOLUTE MAXIMUM RATINGS(1)
PIN CONFIGURATION
TOP VIEW
SO-8
Ref
1
8
NC
–In
2
7
V+
+In
3
6
Output
V–
4
5
Sense
Supply Voltage, V+ to V– .................................................................... 40V
Input Voltage Range .......................................................................... ±80V
Output Short Circuit (to ground) ............................................. Continuous
Operating Temperature .................................................. –55°C to +125°C
Storage Temperature ..................................................... –55°C to +125°C
Junction Temperature .................................................................... +150°C
Lead Temperature (soldering, 10s) ............................................... +300°C
NOTE: (1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods may degrade
device reliability.
ELECTROSTATIC
DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Burr-Brown
recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and
installation procedures can cause damage.
NC = No Connection
ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric
changes could cause the device not to meet its published
specifications.
PACKAGE/ORDERING INFORMATION
PACKAGE
PACKAGE
DRAWING
NUMBER(1)
SPECIFIED
TEMPERATURE
RANGE
PACKAGE
MARKING
ORDERING
NUMBER(2)
TRANSPORT
MEDIA
INA157U
SO-8 Surface-Mount
182
–40°C to +85°C
INA157U
"
"
"
"
"
INA157UA
SO-8 Surface-Mount
182
–40°C to +85°C
INA157UA
"
"
"
"
"
INA157U
INA157U/2K5
INA157UA
INA157UA/2K5
Rails
Tape and Reel
Rails
Tape and Reel
PRODUCT
NOTES: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book. (2) Models with a slash (/) are
available only in Tape and Reel in the quantities indicated (e.g., /2K5 indicates 2500 devices per reel). Ordering 2500 pieces of “INA157U/2K5” will get a single
2500-piece Tape and Reel. For detailed Tape and Reel mechanical information, refer to Appendix B of Burr-Brown IC Data Book.
®
3
INA157
TYPICAL PERFORMANCE CURVES
At TA = +25°C, VS = ±15V, and G = 1/2, unless otherwise noted.
COMMON-MODE REJECTION RATIO vs FREQUENCY
GAIN vs FREQUENCY
100
Common-Mode Rejection Ratio (dB)
10
Voltage Gain (dB)
0
–10
–20
80
60
RTO
40
–30
1k
10k
100k
1M
1k
10M
10k
100k
1M
Frequency (Hz)
Frequency (Hz)
POWER SUPPLY REJECTION RATIO vs FREQUENCY
MAXIMUM OUTPUT VOLTAGE vs FREQUENCY
120
40
100
80
Output Voltage (Vp-p)
Power Supply Rejection (dB)
RTO
–PSRR
60
40
+PSRR
20
10
20
0
0
100
1k
10k
100k
1M
100
1k
10k
100k
1M
Frequency (Hz)
Frequency (Hz)
INPUT COMMON-MODE VOLTAGE
vs OUTPUT VOLTAGE
TOTAL HARMONIC DISTORTION + NOISE
vs FREQUENCY
80
10M
0.1
G = 1/2
VS = ±15V
60
VO = 5Vrms
40
THD+Noise (%)
Common-Mode Voltage (V)
30
20
0
–20
0.010
RL = 100kΩ
RL = 2kΩ
0.001
–40
–60
VREF = 0V
RL = 2kΩ
RL = 600Ω
–80
0.0001
–20
–15
–10
–5
0
5
10
15
20
20
®
INA157
100
1k
Frequency (Hz)
Output Voltage (V)
4
10k 20k
TYPICAL PERFORMANCE CURVES
(CONT)
At TA = +25°C, VS = ±15V, and G = 1/2, unless otherwise noted.
QUIESCENT CURRENT vs TEMPERATURE
SLEW RATE vs TEMPERATURE
4
16
3
14
Slew Rate (V/µs)
Quiescent Current (mA)
–SR
2
1
0
+SR
12
10
8
–75
–50
–25
0
25
50
75
100
125
–75
–50
–25
0
Temperature (°C)
SHORT-CIRCUIT CURRENT vs TEMPERATURE
75
100
125
OUTPUT VOLTAGE SWING vs OUTPUT CURRENT
13
40
Output Voltage Swing (V)
60
Short-Circuit Current (mA)
50
14
80
+ISC
20
0
–20
–ISC
–40
25
50
75
100
85°C
9
–9
85°C
125°C
–10
–11
–12
–14
0
125°C
10
–80
–25
25°C
11
–13
–50
–55°C
12
–60
–75
125
25°C
0
±20
±40
±60
Temperature (°C)
Output Current (mA)
OUTPUT VOLTAGE NOISE SPECTRAL DENSITY
vs FREQUENCY
OUTPUT NOISE VOLTAGE
vs NOISE BANDWIDTH
10k
–55°C
±80
100
Noise Voltage (µVrms)
Voltage Noise (nV/√Hz)
25
Temperature (°C)
1k
100
10
10
1
0.1
1
10
100
1k
10k
100k
1M
1
Frequency (Hz)
10
100
1k
10k
100k
Frequency (Hz)
®
5
INA157
TYPICAL PERFORMANCE CURVES
(CONT)
At TA = +25°C, VS = ±15V, and G = 1/2, unless otherwise noted.
OFFSET VOLTAGE
PRODUCTION DISTRIBUTION
OFFSET VOLTAGE DRIFT
PRODUCTION DISTRIBUTION
35
25
20
Percent of Units (%)
30
25
20
15
10
15
10
5
5
0
–1000
–900
–800
–700
–600
–500
–400
–300
–200
–100
0
100
200
300
400
500
600
700
800
900
1000
0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Offset Voltage Drift (µV/°C)
Offset Voltage (µV)
SMALL-SIGNAL STEP RESPONSE
LARGE-SIGNAL STEP RESPONSE
CL = 500pF
CL = 100pF
5V/div
50mV/div
CL = 500pF
1µs/div
1µs/div
SMALL-SIGNAL OVERSHOOT
vs LOAD CAPACITANCE
70
60
50
Overshoot (%)
Percent of Units (%)
Typical production distribution
of packaged units.
Typical Production
Distribution of
Packaged Units.
40
30
20
RL = 2kΩ
100mV Step
10
0
0
200
400
600
800
Load Capacitance (pF)
®
INA157
6
1000
1200
INPUT VOLTAGE RANGE
APPLICATIONS INFORMATION
The INA157 can accurately measure differential signals
that are above the positive or negative power supply rail. In
a gain of 1/2, the linear common-mode range extends from
3•(V+) – 7.5V to 3•(V–) +7.5V. See the Typical Performance Curve, “Input Common-Mode Range vs Output
Voltage.”
The INA157 is a difference amplifier suitable for a wide
range of general-purpose applications. Figure 1 shows the
basic G = 1/2 configuration. The input and feedback resistors can be reversed to achieve G = 2, as shown in Figure 2.
For applications requiring G = 1, the INA154 is recommended.
Decoupling capacitors are strongly recommended for applications with noisy or high impedance power supplies. The
capacitors should be placed close to the device pins as
shown in Figure 1.
OFFSET VOLTAGE TRIM
The INA157 is laser trimmed for low offset voltage and
drift. Most applications require no external offset adjustment. Figure 3 shows an optional circuit for trimming the
output offset voltage. The output is referred to the output
reference terminal (pin 1), which is normally grounded. A
voltage applied to the Ref terminal will be summed with the
output signal. This can be used to null offset voltage as
shown in Figure 3. The source impedance of a signal
applied to the Ref terminal should be less than 10Ω to
maintain good common-mode rejection.
As shown in Figure 1, the output is referred to the reference
terminal (pin 1). A voltage applied to this pin will be
summed with the output signal. The differential input signal
is connected to pins 2 and 3. The source impedances connected to the inputs must be nearly equal to assure good
common-mode rejection. A 5Ω mismatch in source impedance will degrade the common-mode rejection of a typical
device to approximately 77dB (RTO). If the source has a
known impedance mismatch, an additional resistor in series
with the opposite input can be used to preserve good common-mode rejection.
INA157
–In
V2
V+
V–
5
R2
6kΩ
R1
12kΩ
2
1µF
1µF
6
7
4
INA157
–In
V2
2
R1
12kΩ
+In
R2
6kΩ
V3
1
R4
6kΩ
3
Ref
V3
3
RL
R3
12kΩ
R4
6kΩ
VO = 2 (V3 – V2)
R3
12kΩ
5
6
+In
RL
FIGURE 2. G = 2 Differential Amplifier.
VO = 1/2 (V3 – V2)
G = 1/2
INA157
1
Ref
2
V2
R1
12kΩ
R2
6kΩ
FIGURE 1. G = 1/2 Differential Amplifier (basic power
supply and signal connections).
5
6
20Ω
OPERATING VOLTAGE
V3
The INA157 operates from ±4V to ±18V supplies with
excellent performance. Most behavior remains unchanged
throughout the full operating voltage range. Parameters
which vary significantly with operating voltage are shown in
the Typical Performance Curves.
3
R3
12kΩ
R4
6kΩ
VO = 1/2 (V3 – V2)
Offset Adjustment
Range = ±1mV
VO
1
+15V
250kΩ
100kΩ
10Ω
–15V
FIGURE 3. Offset Adjustment.
®
7
INA157
INA157
6kΩ
2
5
–In
V1
5
BUF634
V0 = 2V1 + V2
12kΩ
V2
2
6
6
6kΩ
1
BUF634 inside feedback
loop contributes no error.
INA157
12kΩ
+In
3
1
(Low IQ mode)
VO
RL
3
FIGURE 4. Precision Summing Amplifier.
FIGURE 6. Boosting Output Current.
The difference amplifier is a highly versatile building
block that is useful in a wide variety of applications. See
the INA105 data sheet for additional applications ideas,
including:
V1
INA157
–In
A1
2
5
• Current Receiver with Compliance to Rails
R2
6
R1
VO
R2
• Precision Average Value Amplifier
• Precision Bipolar Offsetting
1
3
V2
• ±10V Precision Voltage Reference
• ±5V Precision Voltage Reference
• Precision Summing Amplifier with Gain
• Instrumentation Amplifier Guard Drive Generator
A2
+In
• Precision Summing Instrumentation Amplifier
• Precision Absolute Value Buffer
VO = (1 + 2R2/R1) (V2 –V1)
• Precision Voltage-to-Current Converter with Differential
Inputs
• Differential Input Voltage-to-Current Converter for Low
IOUT
The INA157 can be combined with op amps to form a complete instrumentation amplifier with specialized performance characteristics. BurrBrown offers many complete high performance IAs. Products with related
performances are shown at the right.
FEATURE
SIMILIAR COMPLETE
BURR-BROWN IAs
Low Noise
Ultra Low Bias Current (fA)
Low Offset Drift, Low Noise
FET Input (pA)
INA103
INA116
INA114, INA128
INA111, INA121
A1, A2
OPA227
OPA129
OPA277
OPA2134
• Isolating Current Source
• Differential Output Difference Amplifier
• Isolating Current Source with Buffering Amplifier for
Greater Accuracy
• Window Comparator with Window Span and Window
Center Inputs
• Precision Voltage-Controlled Current Source with Buffered Differential Inputs and Gain
• Digitally Controlled Gain of ±1 Amplifier
FIGURE 5. Precision Instrumentation Amplifier.
®
INA157
8