Information furnished by Analog Devices is believed to be accurate and
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use, nor for any infringements of patents or other rights of third parties that
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
a
OP90
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700www.analog.com
Fax: © Analog Devices, Inc.,
Precision Low-Voltage Micropower
Operational Amplifier
PIN CONNECTIONS
8-Lead Epoxy Mini-DIP
(P-Suffix)
8-Lead SO
(S-Suffix)
8
7
6
5
1
2
3
4
NC = NO CONNECT
VOS NULL
–IN
+IN
NC
V+
OUT
VOS NULLV–
FEATURES
Single/Dual Supply Operation: 1.6 V to 36 V,
ⴞ0.8 V to ⴞ18 V
True Single-Supply Operation; Input and Output
Voltage Ranges Include Ground
Low Supply Current: 20 ␮A Max
High Output Drive: 5 mA Min
Low Input Offset Voltage: 150 ␮V Max
High Open-Loop Gain: 700 V/mV Min
Outstanding PSRR: 5.6 ␮V/V Max
Standard 741 Pinout with Nulling to V–
GENERAL DESCRIPTION
The OP90 is a high performance, micropower op amp that
operates from a single supply of 1.6 V to 36 V or from dual
supplies of ±0.8 V to ±18 V. The input voltage range includes
the negative rail allowing the OP90 to accommodate input
signals down to ground in a single-supply operation. The OP90’s
output swing also includes a ground when operating from a
single-supply, enabling “zero-in, zero-out” operation.
The OP90 draws less than 20 µA of quiescent supply current,
while able to deliver over 5 mA of output current to a load. The
input offset voltage is below 150 µV eliminating the need for
*ELECTRONICALLY ADJUSTED ON CHIP
FOR MINIMUM OFFSET VOLTAGE
NULL NULL
–IN
+IN
V+
OUTPUT
V–
**
Figure 1. Simplied Schematic
external nulling. Gain exceeds 700,000 and common-mode
rejection is better than 100 dB. The power supply rejection
ratio of under 5.6 µV/V minimizes offset voltage changes experi-
enced in battery-powered systems.
The low offset voltage and high gain offered by the OP90 bring
precision performance to micropower applications. The minimal
voltage and current requirements of the OP90 suit it for battery
and solar powered applications, such as portable instruments,
remote sensors, and satellites.
REV. C
781/461-3113
2011
OP90
Rev. C | Page 2 of 13
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS
(VS = ±1.5 V to ±15 V, TA = 25°C, unless otherwise noted.)
Parameter
Symbol
Conditions
OP90G
Min Typ
Max
Unit
INPUT OFFSET
VOLTAGE
VOS 125 450 µV
INPUT OFFSET
CURRENT
I
OS
VCM = 0 V 0.4 5 nA
INPUT BIAS
CURRENT
IB VCM = 0 V 4.0 25 nA
LARGE-SIGNAL
VOLTAGE GAIN
AVO
AVO
AVO
AVO
AVO
VS =
±
15 V, VO =
±
10 V
RL = 100 kΩ
RL= 10 kΩ
RL = 2 kΩ
V+ = 5 V, V– = 0
V,
1 V
<
VO
<
4 V
RL = 100 kΩ
RL = 10 kΩ
400 800
200 400
100 200
100 250
70 140
V/mV
V/mV
V/mV
V/mV
V/mV
INPUT VOLTAGE RANGE1 IVR V+ = 5 V, V– = 0 V
VS =
±
15 V
0/4
–15/13.5
V
V
OUTPUT VOLTAGE SWING
V
O
V
OH
VOL
VS =
±
15 V
RL = 10 kΩ
RL = 2 kΩ
V+ = 5 V, V– = 0 V
RL = 2 kΩ
V+ = 5 V, V– = 0 V
RL = 10 kΩ
±
14
±
14.2
±
11
±
12
4.0
4.2
100 500
V
V
V
µV
COMMON-MODE
REJECTION
CMR
CMR
V+ = 5 V, V– = 0
V,
0 V
<
VCM
<
4 V
VS =
±
15
V,
–15
V
<
V
CM
<
13.5
V
80 100
90 120
dB
dB
POWER
SUPPLY
REJECTION RATIO
PSRR
3.2 10
µV/V
SLEW
RATE
SR
VS =
±
15 V 5 12 V/ms
SUPPLY
CURRENT
I
SY
ISY
VS =
±
1.5 V
VS
=
±
15 V
9 15
14 20
µA
µA
CAPACITIVE LOAD
STABILITY
2
AV = 1
No Oscillations 250 650
pF
INPUT NOISE
VOLTAGE
en
p-p
f
O
= 0.1 Hz to 10 Hz
V
S
=
±
15
V
3
µV
p-p
INPUT
RESISTANCE
DIFFERENTIAL
MODE
R
IN
VS =
±
15 V
30
MΩ
INPUT
RESISTANCE
COMMON-MODE
R
INCM
VS =
±
15 V
20
GΩ
NOTES
1Guaranteed by CMR test.
2Guaranteed but not 100% tested.
Specifications subject to change without notice .
–3–
OP90
(VS = ⴞ1.5 V to ⴞ15 V, –55ⴗC TA +125ⴗC, unless otherwise noted.)
Parameter Symbol Conditions Min Typ Max Unit
INPUT OFFSET VOLTAGE V
OS
80 400 µV
AVERAGE INPUT OFFSET
VOLTAGE DRIFT TCV
OS
0.3 2.5 µV/°C
INPUT OFFSET CURRENT I
OS
V
CM
= 0 V 1.5 5 nA
INPUT BIAS CURRENT I
B
V
CM
= 0 V 4.0 20 nA
LARGE-SIGNAL
VOLTAGE GAIN A
VO
V
S
= ±15 V, V
O
= ±10 V
R
L
= 100 kΩ225 400 V/mV
R
L
= 10 kΩ125 240 V/mV
R
L
= 2 kΩ50 110 V/mV
A
VO
V+ = 5 V, V– = 0 V,
1 V < V
O
< 4 V
R
L
= 100 kΩ100 200 V/mV
R
L
= 10 kΩ50 110 V/mV
INPUT VOLTAGE RANGE
*
IVR V+ = 5 V, V– = 0 V 0/3.5 V
V
S
= ±15 V –15/13 5 V
OUTPUT VOLTAGE SWING V
O
V
S
= ±15 V
R
L
= 10 kΩ±13.5 ±13.7 V
R
L
= 2 kΩ±10.5 ±11.5 V
V
OH
V+ = 5 V, V– = 0 V
R
L
= 2 kΩ3.9 4.1 V
V
OL
V+ = 5 V, V– = 0 V
R
L
= 10 kΩ100 500 µV
COMMON-MODE
REJECTION CMR V+ = 5 V, V– = 0 V,
0 V < V
CM
< 3.5 V 85 105 dB
V
S
= ±15 V,
15 V < V
CM
< 13.5 V 95 115 dB
POWER SUPPLY
REJECTION RATIO PSRR 3.2 10 µV/V
SUPPLY CURRENT I
SY
V
S
= ±1.5 V 15 25 µA
V
S
= ±15 V 19 30 µA
NOTE
*Guaranteed by CMR test.
ELECTRICAL CHARACTERISTICS
REV. C
OP90
Rev. C | Page 4 of 13
ELECTRICAL CHARACTERISTICS
(VS = ±1.5 V to ±15 V, –40°C ≤ TA ≤ +85°C for OP90G, unless otherwise noted.)
Parameter
Symbol
Conditions
OP90G
Min Typ
Max
Unit
INPUT OFFSET
VOLTAGE
V
OS
180 675 µV
AVERAGE INPUT
OFFSET
VOLTAGE
DRIFT
TC
V
OS
1.2
5 µ
V
/°C
INPUT OFFSET
CURRENT
I
OS
VCM = 0 V 1.3 7 nA
INPUT BIAS
CURRENT
IB VCM = 0 V 4.0 25 nA
LARGE-SIGNAL
VOLTAGE
GAIN
AVO
AVO
VS =
±
15 V, VO =
±
10 V
RL = 100 kΩ
RL = 10 kΩ
RL = 2 kΩ
V+ = 5 V, V– = 0
V,
1 V
<
VO
<
4 V
RL = 100 kΩ
RL = 10 kΩ
300 600
150 250
75 125
80 160
40 90
V/mV
V/mV
V/mV
V/mV
V/mV
INPUT VOLTAGE
RANGE
*
IVR V+ = 5 V, V– = 0 V
VS =
±
15 V
0/3.5
–15/13.5
V
V
OUTPUT VOLTAGE SWING VO
VOH
VOL
VS =
±
15 V
RL = 10 kΩ
RL = 2 kΩ
V+ = 5 V, V– = 0 V
RL = 2 kΩ
V+ = 5 V, V– = 0 V
RL = 10 kΩ
±
13.5
±
14
±
10.5
±
11.8
3.9
4.1
100 500
V
V
V
µV
COMMON-MODE
REJECTION
CMR
V+ = 5 V, V– = 0
V,
0 V
<
VCM
<
3.5 V
VS =
±
15
V,
–15
V
<
V
CM
<
13.5
V
80 100
90 110
dB
dB
POWER
SUPPLY
REJECTION
RATIO
PSRR
5.6
17.8
µV/V
SUPPLY
CURRENT
ISY VS =
±
1.5 V
VS =
±
15 V
12 25
16 30
µA
µA
NOTE
*
Guaranteed
by CMR test.
OP90
–5–
ABSOLUTE MAXIMUM RATINGS
1
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±18 V
Differential Input Voltage . . . . [(V–) – 20 V] to [(V+) + 20 V]
Common-Mode Input Voltage . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . [(V–) – 20 V] to [(V+) + 20 V]
Output Short-Circuit Duration . . . . . . . . . . . . . . . . Indefinite
Storage Temperature Range
Package . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to +150°C
P Package . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to +150°C
Operating Temperature Range
OP90G . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to +85°C
Junction Temperature (T
J
) . . . . . . . . . . . . . –65°C to +150°C
Lead Temperature (Soldering 60 sec) . . . . . . . . . . . . . . 300°C
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection. Although
the OP90 features proprietary ESD protection circuitry, permanent damage may occur on devices
subjected to high-energy electrostatic discharges. Therefore, proper ESD precautions are
recommended to avoid performance degradation or loss of functionality.
WARNING!
ESD SENSITIVE DEVICE
Package Type
JA2
JC
Unit
8-Lead Plastic DIP (P) 103 43 °C/W
8-Lead SO (S) 158 43 °C/W
NOTES
1
Absolute Maximum Ratings apply to packaged parts, unless otherwise noted.
2
JA
is specified for worst-case mounting conditions; i.e.,
JA
is specified for
device in socket for
REV. C
S
P-DIP; θ is specified for devices soldered to printed circuit
board for SO package.
JA
OP90
–6–
TEMPERATURE – C
INPUT OFFSET VOLTAGE – ␮V
100
80
0
–75 –50 125
025 100
40
60
20
7550–25
V
S
= ⴞ15V
TPC 1. Input Offset Voltage
vs. Temperature
TEMPERATURE – C
SUPPLY CURRENT – ␮A
22
18
2
–75 –50 125
025 100
10
14
6
7550–25
NO LOAD
V
S
= ⴞ1.5V
20
16
8
12
4
V
S
= ⴞ15V
TPC 4. Supply Current vs.
Temperature
FREQUENCY – Hz
CLOSED-LOOP GAIN – dB
60
40
–2010 100k
1k
20
0
10k100
V
S
= ⴞ15V
T
A
= 25ⴗC
TPC 7. Closed-Loop Gain
vs. Frequency
–Typical Performance Characteristics
TEMPERATURE – C
INPUT OFFSET CURRENT – nA
1.6
0.2
–75 –50 125
025 100
0.8
1.0
0.4
7550–25
1.4
1.2
0.6
VS = ⴞ15V
TPC 2. Input Offset Current
vs. Temperature
SINGLE-SUPPLY VOLTAGE – V
OPEN-LOOP GAIN – V/mV
600
0030
10 15 25
300
100
205
500
400
200
R
L
= 10k⍀
T
A
= 25 C
T
A
= 85 C
T
A
= 125 C
TPC 5. Open-Loop Gain vs.
Single-Supply Voltage
LOAD RESISTANCE – ⍀
OUTPUT VOLTAGE SWING – V
6
4
0
100 100k
1k
3
1
10k
V+ = 5V, V– = 0V
T
A
= 25ⴗC
5
2
TPC 8. Output Voltage Swing
vs. Load Resistance
TEMPERATURE – C
INPUT BIAS CURRENT – nA
4.2
4.0
3.0
–75 –50 125
025 100
3.6
3.8
3.4
7550–25
VS = ⴞ15V
3.2
TPC 3. Input Bias Current
vs. Temperature
FREQUENCY – Hz
OPEN-LOOP GAIN – dB
140
120
0
0.1 1 100k
10 100 10k
80
100
60
1k
VS = ⴞ15V
TA = 25ⴗC
RL = 100k⍀
40
20
GAIN
45
0
90
135
180
PHASE SHIFT – DEG
TPC 6. Open-Loop Gain and
Phase Shift vs. Frequency
LOAD RESISTANCE – ⍀
OUTPUT SWING – V
16
12
0
100 100k
1k
8
4
10k
TA = 25ⴗC
VS = ⴞ15V
14
6
10
2
POSITIVE
NEGATIVE
TPC 9. Output Voltage Swing
vs. Load Resistance
REV. C
–7–
OP90
+18V
–18V
2
3
4
6
7
OP90
Figure 2. Burn-In Circuit
APPLICATION INFORMATION
Battery-Powered Applications
The OP90 can be operated on a minimum supply voltage of 1.6 V,
or with dual supplies ±0.8 V, and draws only 14 pA of supply
current. In many battery-powered circuits, the OP90 can be
continuously operated for thousands of hours before requiring
battery replacement, reducing equipment down time and
operating cost.
High-performance portable equipment and instruments frequently
use lithium cells because of their long shelf-life, light weight, and
high-energy density relative to older primary cells. Most lithium
cells have a nominal output voltage of 3 V and are noted for a
flat discharge characteristic. The low-supply voltage requirement
of the OP90, combined with the flat discharge characteristic of
the lithium cell, indicates that the OP90 can be operated over
the entire useful life of the cell. Figure 1 shows the typical dis-
charge characteristic of a 1Ah lithium cell powering an OP90
which, in turn, is driving full output swing into a 100 kΩ load.
FREQUENCY – Hz
POWER SUPPLY REJECTION – dB
120
100
20
11k
10 100
T
A
= 25ⴗC
60
80
40
POSITIVE SUPPLY
NEGATIVE SUPPLY
TPC 10. Power Supply Rejection
vs. Frequency
FREQUENCY – Hz
CURRENT NOISE DENSITY – pA/ 兹Hz
100
0.1
0.1 1k
110
10
1
V
S
= ⴞ15V
T
A
= 25ⴗC
100
TPC 13. Current Noise Density
vs. Frequency
FREQUENCY – Hz
COMMON-MODE REJECTION – dB
140
120
40
11k
10 100
V
S
= ⴞ15V
T
A
= 25ⴗC
80
100
60
TPC 11. Common-Mode Rejection
vs. Frequency
T
A
= 25ⴗC
V
S
= ⴞ15V
A
V
= +1
R
L
= 10k⍀
C
L
= 500pF
TPC 14. Small-Signal Transient
Response
FREQUENCY – Hz
NOISE VOLTAGE DENSITY – nV/ 兹Hz
1000
1
0.1 1k
110
100
10
V
S
= ⴞ15V
T
A
= 25ⴗC
100
TPC 12. Noise Voltage Density
vs. Frequency
T
A
= 25ⴗC
V
S
= ⴞ15V
A
V
= +1
R
L
= 10k⍀
C
L
= 500pF
TPC 15. Large-Signal Transient
Response
REV. C
OP90
–8–
Single-Supply Output Voltage Range
In single-supply operation, the OP90’s input and output ranges
include ground. This allows true “zero-in, zero-out” operation.
The output stage provides an active pull-down to around 0.8 V
above ground. Below this level, a load resistance of up to 1 MΩ
to ground is required to pull the output down to zero.
In the region from ground to 0.8 V, the OP90 has voltage gain
equal to the data sheet specification. Output current source
capatibility is maintained over the entire voltage range includ-
ing ground.
APPLICATIONS
Battery-Powered Voltage Reference
The circuit of Figure 6 is a battery-powered voltage reference
that draws only 17 µA of supply current. At this level, two AA
cells can power this reference over 18 months. At an output voltage
of 1.23 V @ 25°C, drift of the reference is only at 5.5 µV/°C over
the industrial temperature range. Load regulation is 85 µV/mA
with line regulation at 120 µV/V.
Design of the reference is based on the bandgap technique.
Scaling of resistors R1 and R2 produces unequal currents in Q1
and Q2. The resulting V
BE
mismatch creates a temperature
proportional voltage across R3 which, in turn, produces a larger
temperature-proportional voltage across R4 and R5. This volt-
age appears at the output added to the V
BE
of Q1, which has an
opposite temperature coefficient. Adjusting the output to l.23 V
at 25°C produces minimum drift over temperature. Bandgap
references can have start-up problems. With no current in R1
and R2, the OP90 is beyond its positive input range limit and
has an undefined output state. Shorting Pin 5 (an offset adjust
pin) to ground, forces the output high under these conditions
and ensures reliable start-up without significantly degrading the
OP90’s offset drift.
4
2
35
6
7
OP90
R1
240k⍀
R2
1.5M⍀
C1
1000pF
V+
(2.5V TO 36V)
V
OUT
(1.23V @ 25ⴗC)
6
5
7
3
2
1
R3
68k⍀
R4
130k⍀
R5
20k⍀
OUTPUT
ADJUST
MAT-01AH
Figure 6. Battery-Powered Voltage Reference
HOURS
LITHIUM SULPHUR DIOXIDE
CELL VOLTAGE – V
4
3
00 2000 7000
4000
2
1
1000 3000 60005000
Figure 3. Lithium Sulphur Dioxide Cell Discharge
Characteristic with OP90 and 100 k
Ω
Load
Input Voltage Protection
The OP90 uses a PNP input stage with protection resistors in
series with the inverting and noninverting inputs. The high
breakdown of the PNP transistors coupled with the protection
resistors provides a large amount of input protection, allowing
the inputs to be taken 20 V beyond either supply without dam-
aging the amplifier.
Offset Nulling
The offset null circuit of Figure 4 provides 6 mV of offset adjust-
ment range. A 100 kΩ resistor placed in a series with the wiper
of the offset null potentiometer, as shown in Figure 5, reduces
the offset adjustment range to 400 µV and is recommended for
applications requiring high null resolution. Offset nulling does not
affect TCV
OS
performance.
TEST CIRCUITS
V+
1
2
3
5
6
7
OP90 4
100k⍀
V–
Figure 4. Offset Nulling Circuit
V+
1
2
3
5
6
7
OP90 4
100k⍀
V–
100k⍀
Figure 5. High Resolution Offset Nulling Circuit
REV. C
OP90
–9–
Single Op Amp Full-Wave Rectifier
Figure 7 shows a full-wave rectifier circuit that provides the
absolute value of input signals up to ±2.5 V even though operated
from a single 5 V supply. For negative inputs, the amplifier acts
as a unity-gain inverter. Positive signals force the op amp output
to ground. The 1N914 diode becomes reversed-biased and the
signal passes through R1 and R2 to the output. Since output
impedance is dependent on input polarity, load impedances
cause an asymmetric output. For constant load impedances, this
can be corrected by reducing R2. Varying or heavy loads can be
buffered by a second OP90. Figure 8 shows the output of the
full-wave rectifier with a 4 V
p-p
, 10 Hz input signal.
+5V
2
3
4
6
OP90
7
R3
100k⍀
HP5082-2800
VIN
R1
10k⍀
R2
10k⍀
1N914
VOUT
Figure 7. Single Op Amp Full-Wave Rectifier
Figure 8. Output of Full-Wave Rectifier with 4 V
p-p
,
10 Hz Input
2-WIRE 4 mA TO 20 mA CURRENT TRANSMITTER
The current transmitter of Figure 9 provides an output of 4 mA
to 20 mA that is linearly proportional to the input voltage.
Linearity of the transmitter exceeds 0.004% and line rejection is
0.0005%/volt.
Biasing for the current transmitter is provided by the REF-02EZ.
The OP90 regulates the output current to satisfy the current
summation at the noninverting node:
IR
VR
R
VR
R
OUT
IN
=+
1
6
5
2
55
1
For the values shown in Figure 9,
IVmA
OUT IN
=
+
16
100 4
Ω
giving a full-scale output of 20 mA with a 100 mV input.
Adjustment of R2 will provide an offset trim and adjustment of
R1 will provide a gain trim. These trims do not interact since
the noninverting input of the OP90 is at virtual ground. The
Schottky diode, D1, prevents input voltage spikes from pulling
the noninverting input more than 300 mV below the inverting
input. Without the diode, such spikes could cause phase reversal of
the OP90 and possible latch-up of the transmitter. Compliance of
this circuit is from 10 V to 40 V. The voltage reference output
can provide up to 2 mA for transducer excitation.
2
3
4
6
7
IOUT = 16VIN
100⍀
+ 4mA
VIN
R2
5k⍀
6
4
2
R6
100⍀
R3
4.7k⍀
R4
100k⍀
R1
1M⍀
D1
HP
5082-
2800
R5
80k⍀
+5V
REFERENCE
2mA MAX
–
+
IOUT RL
2N1711
V+
(10V TO 40V)
OP90
REF-02EZ
Figure 9. 2-Wire 4 mA to 20mA Transmitter
REV. C
OP90
–10–
Micropower Voltage-Controlled Oscillator
Two OP90s in combination with an inexpensive quad CMOS
switch comprise the precision VCO of Figure 10. This circuit
provides triangle and square wave outputs and draws only 50 µA
from a single 5 V supply. A1 acts as an integrator; S1 switches
the charging current symmetrically to yield positive and negative
ramps. The integrator is bounded by A2 which acts as a Schmitt
trigger with a precise hysteresis of 1.67 V, set by resistors R5,
R6, and R7, and associated CMOS switches. The resulting output
of A1 is a triangular wave with upper and lower levels of 3.33 V
and 1.67 V. The output of A2 is a square wave with almost
rail-to-rail swing. With the components shown, frequency of
operation is given by the equation:
fV V HzV
OUT CONTROL
=
()
×10 /
but this is easily changed by varying C1. The circuit operates
well up to a few hundred hertz.
Micropower Single-Supply Instrumentation Amplifier
The simple instrumentation amplifier of Figure 11 provides over
110 dB of common-mode rejection and draws only 15 µA of
supply current. Feedback is to the trim pins rather than to the
inverting input. This enables a single amplifier to provide differ-
ential to single-ended conversion with excellent common-mode
rejection. Distortion of the instrumentation amplifier is that of a
differential pair, so the circuit is restricted to high gain applica-
3
7
C1
75nF
6
4
2
R3
100k⍀
R4
200k⍀
R1
200k⍀
R2
200k⍀
VCONTROL
+5V
TRIANGLE
OUT
R8
200k⍀
+5V
R5
200k⍀
3
7
6
4
2
SQUARE
OUT
R6
200k⍀
R7
200k⍀
IN/OUT
OUT/IN
IN/OUT
CONT
CONT
CONT
1
IN/OUT
IN/OUT
VSS
+5V
CONT
2
3
4
5
6
7
14
13
12
11
10
9
8
CD4066
+5V
+5V
+5V
VDD
OUT/IN
OUT/IN
OUT/IN
OP90
A2
S1
S2
S3
S4
OP90
A1
Figure 10. Micropower Voltage Controlled Oscillator
tions. Nonlinearity is less than 0.1% for gains of 500 to 1000
over a 2.5 V output range. Resistors R3 and R4 set the voltage
gain and, with the values shown, yield a gain of 1000. Gain
tempco of the instrumentation amplifier is only 50 ppm/°C.
Offset voltage is under 150 µV with drift below 2 µV/°C. The
OP90’s input and output voltage ranges include the negative
rail which allows the instrumentation amplifier to provide true
“zero-in, zero-out” operation.
R1
4.3M⍀
R4
3.9M⍀
R3
1M⍀
R2
500k⍀
GAIN
ADJUST
V
OUT
3
7
6
4
2
5
–IN
1
+IN
0.1␮F
+5V
OP90
Figure 11. Micropower Single-Supply Instrumentation
Amplifier
REV. C
OP90
–11–
Single-Supply Current Monitor
Current monitoring essentially consists of amplifying the voltage
drop across a resistor placed in a series with the current to be
measured. The difficulty is that only small voltage drops can be
tolerated and with low precision op amps this greatly limits the
overall resolution. The single supply current monitor of Figure 12
has a resolution of 10 µA and is capable of monitoring 30 mA of
current. This range can be adjusted by changing the current
sense resistor R1. When measuring total system current, it may
be necessary to include the supply current of the current moni-
tor, which bypasses the current sense resistor, in the final result.
This current can be measured and calibrated (together with the
residual offset) by adjustment of the offset trim potentiometer,
R2. This produces a deliberate offset that is temperature
dependent. However, the supply current of the OP90 is also
proportional to temperature and the two effects tend to track.
Current in R4 and R5, which also bypasses R1, can be accounted
for by a gain trim.
R1
1⍀
R4
9.9k⍀
R2
100k⍀
R3
100k⍀
376
4
25
1
V+
R5
100⍀
I
TEST
V
OUT
= 100mV/mA (I
TEST
)
TO CIRCUIT
UNDER TEST
–
+
OP90
Figure 12. Single-Supply Current Monitor
REV. C
+
−
OP90
Rev. C | Page 12 of 13
OUTLINE DIMENSIONS
Figure 1. 8-Lead Plastic Dual In-Line Package [PDIP]
Narrow Body
(N-8)
Dimensions shown in inches and (millimeters)
Figure 2. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body
(R-8)
Dimensions shown in millimeters and (inches)
ORDERING GUIDE
Model1 Temperature Range Package Description Package Option
OP90GPZ −40°C to +85°C 8-Lead PDIP N-8
OP90GS −40°C to +85°C 8-Lead SOIC_N R-8
OP90GS-REEL −40°C to +85°C 8-Lead SOIC_N R-8
OP90GS-REEL7 −40°C to +85°C 8-Lead SOIC_N R-8
OP90GSZ −40°C to +85°C 8-Lead SOIC_N R-8
OP90GSZ-REEL −40°C to +85°C 8-Lead SOIC_N R-8
OP90GSZ-REEL7 −40°C to +85°C 8-Lead SOIC_N R-8
1 Z = RoHS Compliant Part.
COM P LIANT TO JEDEC S TANDARDS MS-001
CONTROL LING DIME NS IONS ARE IN INCHE S ; M ILLIME TER DI M ENSIO NS
(I N PARENTHES ES ) ARE ROUNDED- OFF INCH EQUIVALENTS FOR
REFE RENCE ONLY AND ARE NO T APP ROPRI ATE FOR USE IN DES IGN.
CORNER L E ADS MAY BE CONFIG URE D AS WHO LE OR HAL F L E ADS .
070606-A
0.022 ( 0 .56)
0.018 ( 0 .46)
0.014 ( 0 .36)
SEATING
PLANE
0.015
(0.38)
MIN
0.210 ( 5.33)
MAX
0.150 ( 3 .81)
0.130 ( 3 .30)
0.115 (2.92)
0.070 ( 1 . 78)
0.060 ( 1 . 52)
0.045 ( 1 . 14)
8
14
5
0.280 ( 7 .11)
0.250 ( 6 . 35)
0.240 ( 6 . 10)
0.100 ( 2 . 54)
BSC
0.40 0 (10.16)
0.36 5 (9.27)
0.35 5 (9.02)
0.06 0 (1.52)
MAX
0.43 0 (10.92)
MAX
0.014 ( 0 .36)
0.010 ( 0 .25)
0.008 ( 0 .20)
0.325 ( 8.26)
0.310 ( 7.87)
0.300 ( 7.62)
0.19 5 (4.95)
0.13 0 (3.30)
0.115 (2.92)
0.01 5 (0.38)
GAUGE
PLANE
0.005 ( 0 .13)
MIN
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
COMPLIANT TO JEDEC STANDARDS MS-012-AA
012407-A
0.25 (0.0098)
0.17 (0.0067)
1.27 (0.0500)
0.40 (0.0157)
0.50 (0.0196)
0.25 (0.0099) 45°
8°
0°
1.75 (0.0688)
1.35 (0.0532)
SEATING
PLANE
0.25 (0.0098)
0.10 (0.0040)
4
1
85
5.00 (0.1968)
4.80 (0.1890)
4.00 (0.1574)
3.80 (0.1497)
1.27 (0.0500)
BSC
6.20 (0.2441)
5.80 (0.2284)
0.51 (0.0201)
0.31 (0.0122)
COPLANARITY
0.10
OP90
Rev. C | Page 13 of 13
REVISION HISTORY
12/11—Rev. B to Rev. C
Deleted 8-Lead Hermetic DIP (Z-Suffix) Package
(Q-8) ..................................................................................... Universal
Changes to Electrical Characteristics ............................................ 2
Changes to Electrical Characteristics ............................................ 4
Changes to Absolute Maximum Ratings ....................................... 5
Changes to Figure 7, 2-Wire 4 mA to 20 mA Current
Transmitter Section, and Figure 9 .................................................. 9
Changes to Figure 10 and Figure 11............................................. 10
Changes to Figure 12 ...................................................................... 11
Updated Outline Dimensions ....................................................... 12
Changes to Ordering Guide .......................................................... 12
5/02—Rev. A to Rev. B
Edits to 8-Lead SOIC Package (R-8) ............................................ 12
9/01—Rev. 0 to Rev. A
Edits to Pin Connections ................................................................. 1
Edits to Electrical Characteristics ......................................... 2, 3, 4
Edits to Ordering Information ........................................................ 5
Edits to Absolute Maximum Ratings .............................................. 5
Edits to Package Type ....................................................................... 5
Deleted OP90 Dice Characteristics ................................................. 5
Deleted Wafer Test Limits ................................................................ 5
©2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D00321-0-12/11(C)