a
Precision Low-Voltage Micropower
Operational Amplifier
OP90
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–
PIN CONNECTIONS
8-Lead Epoxy Mini-DIP
(P-Suffix)
8-Lead SO
(S-Suffix)
8
NC
2
7
V+
+IN 3
6
OUT
V– 4
5
VOS NULL
VOS NULL 1
–IN
GENERAL DESCRIPTION
NC = NO CONNECT
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
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 experienced 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.
V+
+IN
OUTPUT
–IN
*
NULL
*
NULL
V–
*ELECTRONICALLY ADJUSTED ON CHIP
FOR MINIMUM OFFSET VOLTAGE
Figure 1. Simplied Schematic
REV. C
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
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.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
www.analog.com
Fax: 781/461-3113
© Analog Devices, Inc., 2011
OP90
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS
(VS = ±1.5 V to ±15 V, TA = 25°C, unless otherwise noted.)
Min
OP90G
Typ
125
Max Unit
450 µV
Parameter
INPUT OFFSET VOLTAGE
Symbol Conditions
INPUT OFFSET CURRENT
IOS
VCM = 0 V
0.4
5
nA
INPUT BIAS CURRENT
IB
VCM = 0 V
4.0
25
nA
VOS
LARGE-SIGNAL
VOLTAGE GAIN
AVO
AVO
AVO
AVO
AVO
INPUT VOLTAGE RANGE1
IVR
OUTPUT VOLTAGE SWING
VO
VOH
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
V+ = 5 V, V– = 0 V
VS = ± 15 V
800
400
200
V/mV
V/mV
V/mV
100
70
250
140
V/mV
V/mV
0/4
V
–15/13.5
V
VS = ± 15 V
RL = 10 kΩ
± 14
± 14.2
V
RL = 2 kΩ
± 11
± 12
V
4.0
4.2
V
V+ = 5 V, V– = 0 V
RL = 2 kΩ
VOL
400
200
100
V+ = 5 V, V– = 0 V
100
RL = 10 kΩ
COMMON-MODE
REJECTION
CMR
CMR
V+ = 5 V, V– = 0 V,
0 V < VCM < 4 V
VS = ± 15 V,
–15 V < VCM < 13.5 V
500
µV
80
100
dB
90
120
dB
POWER SUPPLY
REJECTION RATIO
PSRR
SLEW RATE
SR
VS = ± 15 V
SUPPLY CURRENT
ISY
VS = ± 1.5 V
9
15
µA
ISY
VS = ± 15 V
14
20
µA
5
10
12
µV/V
V/ms
AV = 1
CAPACITIVE LOAD
STABILITY2
INPUT NOISE VOLTAGE
3.2
650
pF
VS = ± 15 V
3
µV p-p
No Oscillations
en p-p
250
fO = 0.1 Hz to 10 Hz
INPUT RESISTANCE
DIFFERENTIAL MODE
RIN
VS = ± 15 V
30
MΩ
INPUT RESISTANCE
COMMON-MODE
RINCM
VS = ± 15 V
20
GΩ
NOTES
1Guaranteed by CMR test.
2Guaranteed but not 100% tested.
Specifications subject to change without notice.
Rev. C | Page 2 of 13
OP90
ELECTRICAL CHARACTERISTICS
Parameter
Symbol
INPUT OFFSET VOLTAGE
(VS = ⴞ1.5 V to ⴞ15 V, –55ⴗC TA +125ⴗC, unless otherwise noted.)
Typ
Max
Unit
VOS
80
400
µV
AVERAGE INPUT OFFSET
VOLTAGE DRIFT
TCVOS
0.3
2.5
µV/°C
INPUT OFFSET CURRENT
IOS
VCM = 0 V
1.5
5
nA
INPUT BIAS CURRENT
IB
VCM = 0 V
4.0
20
nA
LARGE-SIGNAL
VOLTAGE GAIN
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
AVO
Conditions
Min
INPUT VOLTAGE RANGE*
IVR
V+ = 5 V, V– = 0 V
VS = ± 15 V
OUTPUT VOLTAGE SWING
VO
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
VOH
VOL
COMMON-MODE
REJECTION
CMR
POWER SUPPLY
REJECTION RATIO
PSRR
SUPPLY CURRENT
ISY
V+ = 5 V, V– = 0 V,
0 V < VCM < 3.5 V
VS = ± 15 V,
15 V < VCM < 13.5 V
VS = ± 1.5 V
VS = ± 15 V
NOTE
*Guaranteed by CMR test.
REV. C
–3–
225
125
50
400
240
110
V/mV
V/mV
V/mV
100
50
200
110
V/mV
V/mV
0/3.5
–15/13 5
V
V
± 13.5
± 10.5
± 13.7
± 11.5
V
V
3.9
4.1
V
100
500
µV
85
105
dB
95
115
dB
3.2
10
µV/V
15
19
25
30
µA
µA
OP90
ELECTRICAL CHARACTERISTICS
(VS = ±1.5 V to ±15 V, –40°C ≤ TA ≤ +85°C for OP90G, unless otherwise noted.)
Unit
µV
1.2
5
µV/°C
VCM = 0 V
1.3
7
nA
IB
VCM = 0 V
4.0
25
nA
AVO
VS = ± 15 V, VO = ± 10 V
RL = 100 kΩ
300
600
RL = 10 kΩ
150
250
V/mV
RL = 2 kΩ
75
125
V/mV
Symbol
VOS
AVERAGE INPUT OFFSET
VOLTAGE DRIFT
TCVOS
INPUT OFFSET CURRENT
IOS
INPUT BIAS CURRENT
LARGE-SIGNAL VOLTAGE
GAIN
AVO
Min
Conditions
V+ = 5 V, V– = 0 V,
1 V < VO < 4 V
IVR
OUTPUT VOLTAGE SWING
VO
VOH
80
160
V/mV
RL = 10 kΩ
40
90
V/mV
V+ = 5 V, V– = 0 V
VS = ± 15 V
0/3.5
V
–15/13.5
V
VS = ± 15 V
RL = 10 kΩ
± 13.5
± 14
RL = 2 kΩ
± 10.5
± 11.8 V
V+ = 5 V, V– = 0 V
3.9
CMR
100
VS = ± 15 V,
–15 V < VCM < 13.5 V
PSRR
SUPPLY CURRENT
ISY
500
µV
V+ = 5 V, V– = 0 V,
80
0 V < VCM < 3.5 V
POWER SUPPLY REJECTION
RATIO
V
4.1
V+ = 5 V, V– = 0 V
RL = 10 kΩ
COMMON-MODE
REJECTION
V
RL = 2 kΩ
VOL
V/mV
RL = 100 kΩ
INPUT VOLTAGE RANGE*
OP90G
Typ
180
Max
675
Parameter
INPUT OFFSET VOLTAGE
VS = ± 1.5 V
VS = ± 15 V
NOTE
*Guaranteed by CMR test.
Rev. C | Page 4 of 13
dB
100
90
110
dB
5.6
17.8
µV/V
12
25
µA
16
30
µA
OP90
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
S Package . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to +150°C
P Package . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to +150°C
Operating Temperature Range
OP90G . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to +85°C
Junction Temperature (TJ) . . . . . . . . . . . . . –65°C to +150°C
Lead Temperature (Soldering 60 sec) . . . . . . . . . . . . . . 300°C
Package Type
JA2
JC
Unit
8-Lead Plastic DIP (P)
8-Lead SO (S)
103
158
43
43
°C/W
°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 P-DIP; θJA is specified for devices soldered to printed circuit
board for SO package.
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.
REV. C
–5–
WARNING!
ESD SENSITIVE DEVICE
OP90 –Typical Performance Characteristics
100
1.6
4.2
VS = ⴞ15V
60
40
20
0
–75 –50 –25 0
25
50
75
TEMPERATURE – C
1.4
1.2
1.0
0.8
0.6
TPC 1. Input Offset Voltage
vs. Temperature
3.6
3.4
3.2
VS = ⴞ15V
3.0
–75 –50 –25 0
25
50
75 100 125
TEMPERATURE – C
100 125
TPC 2. Input Offset Current
vs. Temperature
22
TPC 3. Input Bias Current
vs. Temperature
140
600
NO LOAD
TA = 25 C
OPEN-LOOP GAIN – V/mV
18
16
14
12 VS = ⴞ15V
10
8 V = ⴞ1.5V
S
6
400
120
OPEN-LOOP GAIN – dB
500
TA = 85 C
300
TA = 125 C
200
100
0
100 125
TPC 4. Supply Current vs.
Temperature
40
20
0
1k
10k
FREQUENCY – Hz
TPC 7. Closed-Loop Gain
vs. Frequency
100k
OUTPUT VOLTAGE SWING – V
6
VS = ⴞ15V
TA = 25ⴗC
100
5
10
15
20
25
SINGLE-SUPPLY VOLTAGE – V
GAIN
80
45
60
90
40
135
20
180
0
0.1
30
TPC 5. Open-Loop Gain vs.
Single-Supply Voltage
60
CLOSED-LOOP GAIN – dB
0
1
10
100
1k
FREQUENCY – Hz
10k
100k
TPC 6. Open-Loop Gain and
Phase Shift vs. Frequency
16
V+ = 5V, V– = 0V
TA = 25ⴗC
POSITIVE
14
5
NEGATIVE
OUTPUT SWING – V
2
–75 –50 –25 0
25
50
75
TEMPERATURE – C
0
100
4
–20
10
VS = ⴞ15V
TA = 25ⴗC
RL = 100k⍀
RL = 10k⍀
20
SUPPLY CURRENT – A
3.8
0.4
0.2
25
50
75
–75 –50 –25 0
TEMPERATURE – C
100 125
4.0
4
3
2
12
10
8
6
4
1
0
100
2
1k
10k
LOAD RESISTANCE – ⍀
100k
TPC 8. Output Voltage Swing
vs. Load Resistance
–6–
0
100
TA = 25ⴗC
VS = ⴞ15V
1k
10k
LOAD RESISTANCE – ⍀
100k
TPC 9. Output Voltage Swing
vs. Load Resistance
REV. C
PHASE SHIFT – DEG
80
INPUT BIAS CURRENT – nA
INPUT OFFSET CURRENT – nA
INPUT OFFSET VOLTAGE – V
VS = ⴞ15V
OP90
120
140
1000
COMMON-MODE REJECTION – dB
POWER SUPPLY REJECTION – dB
NEGATIVE SUPPLY
100
80
POSITIVE SUPPLY
60
40
20
NOISE VOLTAGE DENSITY – nV/ 兹Hz
VS = ⴞ15V
TA = 25ⴗC
TA = 25ⴗC
120
100
80
60
40
1
1k
10
100
FREQUENCY – Hz
TPC 10. Power Supply Rejection
vs. Frequency
1
10
100
FREQUENCY – Hz
1k
TPC 11. Common-Mode Rejection
vs. Frequency
VS = ⴞ15V
TA = 25ⴗC
100
10
1
0.1
1
10
100
FREQUENCY – Hz
1k
TPC 12. Noise Voltage Density
vs. Frequency
CURRENT NOISE DENSITY – pA/ 兹Hz
100
VS = ⴞ15V
TA = 25ⴗC
10
1
0.1
0.1
1
1k
10
100
FREQUENCY – Hz
TPC 13. Current Noise Density
vs. Frequency
6
3
4
–18V
Figure 2. Burn-In Circuit
REV. C
TPC 15. Large-Signal Transient
Response
APPLICATION INFORMATION
Battery-Powered Applications
7
OP90
TA = 25ⴗC
VS = ⴞ15V
AV = +1
RL = 10k⍀
CL = 500pF
TPC 14. Small-Signal Transient
Response
+18V
2
TA = 25ⴗC
VS = ⴞ15V
AV = +1
RL = 10k⍀
CL = 500pF
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 discharge characteristic of a 1Ah lithium cell powering an OP90
which, in turn, is driving full output swing into a 100 kΩ load.
–7–
OP90
Single-Supply Output Voltage Range
LITHIUM SULPHUR DIOXIDE
CELL VOLTAGE – V
4
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.
3
2
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 including ground.
1
0
0
APPLICATIONS
Battery-Powered Voltage Reference
1000 2000 3000 4000 5000 6000 7000
HOURS
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.
Figure 3. Lithium Sulphur Dioxide Cell Discharge
Characteristic with OP90 and 100 kΩ 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 damaging the amplifier.
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 VBE mismatch creates a temperature
proportional voltage across R3 which, in turn, produces a larger
temperature-proportional voltage across R4 and R5. This voltage appears at the output added to the VBE 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.
Offset Nulling
The offset null circuit of Figure 4 provides 6 mV of offset adjustment 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 TCVOS performance.
TEST CIRCUITS
V+
2
V+
(2.5V TO 36V)
7
OP90
3
C1
1000pF
6
4
R1
240k⍀
R2
1.5M⍀
5
7
2
1
6
OP90
100k⍀
3
VOUT
(1.23V @ 25ⴗC)
5
4
V–
Figure 4. Offset Nulling Circuit
1
V+
MAT-01AH
2
3
2
7
OP90
3
6
5
R3
6
4
68k⍀
5
1
7
R4
130k⍀
100k⍀
R5
20k⍀
OUTPUT
ADJUST
100k⍀
V–
Figure 5. High Resolution Offset Nulling Circuit
Figure 6. Battery-Powered Voltage Reference
–8–
REV. C
OP90
Single Op Amp Full-Wave Rectifier
2-WIRE 4 mA TO 20 mA CURRENT TRANSMITTER
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 Vp-p, 10 Hz input signal.
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:
IOUT =
1 VIN R5 5V R5
+
R6 R2
R1
For the values shown in Figure 9,
R2
16
IOUT =
V + 4 mA
100 Ω IN
10k⍀
+5V
R1
VIN
2
7
10k⍀
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.
1N914
6
OP90
VOUT
3
4
HP5082-2800
R3
100k⍀
Figure 7. Single Op Amp Full-Wave Rectifier
Figure 8. Output of Full-Wave Rectifier with 4 Vp-p,
10 Hz Input
+5V
REFERENCE
2mA MAX
6
2
V+
(10V TO 40V)
4
R1
1M⍀
2
7
6
OP90
R2
2N1711
3
+
4
5k⍀
VIN
REF-02EZ
D1
HP
50822800
R3
4.7k⍀
R4
100k⍀
–
R6
100⍀
R5
IOUT
80k⍀
IOUT = 16VIN + 4mA
100⍀
Figure 9. 2-Wire 4 mA to 20mA Transmitter
REV. C
–9–
RL
OP90
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:
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.
+5V
0.1F
fOUT = VCONTROL (V ) × 10 Hz / V
7
2
–IN
+IN
1
4
R4
3.9M⍀
R3
1M⍀
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 differential 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-
Figure 11. Micropower Single-Supply Instrumentation
Amplifier
+5V
C1
R1
2
200k⍀
R2
3
75nF
R5
200k⍀
+5V
7
6
OP90
A1
200k⍀
R3
100k⍀
VOUT
R2
500k⍀
GAIN
ADJUST
R1
4.3M⍀
Micropower Single-Supply Instrumentation Amplifier
+5V
5
3
but this is easily changed by varying C1. The circuit operates
well up to a few hundred hertz.
VCONTROL
6
OP90
2
OP90
A2
3
4
R4
200k⍀
7
6
SQUARE
OUT
4
TRIANGLE
OUT
R8
+5V
1 IN/OUT
200k⍀
CD4066
VDD
14
+5V
R6
200k⍀
R7
200k⍀
S1
CONT 13
2 OUT/IN
3 OUT/IN
S2
IN/OUT 11
4 IN/OUT
5 CONT
CONT 12
S3
OUT/IN 10
OUT/IN 9
6 CONT
+5V
S4
7
VSS
IN/OUT 8
Figure 10. Micropower Voltage Controlled Oscillator
–10–
REV. C
OP90
Single-Supply Current Monitor
V+
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 monitor, 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.
REV. C
+
TO CIRCUIT
UNDER TEST
–
3
+
7
OP90
ITEST
2
−
1
R1
1⍀
R5
100⍀
R2
100k⍀
5
6
4
VOUT = 100mV/mA (ITEST)
R4
9.9k⍀
R3
100k⍀
Figure 12. Single-Supply Current Monitor
–11–
OP90
OUTLINE DIMENSIONS
0.400 (10.16)
0.365 (9.27)
0.355 (9.02)
8
5
1
4
0.280 (7.11)
0.250 (6.35)
0.240 (6.10)
0.100 (2.54)
BSC
0.325 (8.26)
0.310 (7.87)
0.300 (7.62)
0.060 (1.52)
MAX
0.210 (5.33)
MAX
0.015
(0.38)
MIN
0.150 (3.81)
0.130 (3.30)
0.115 (2.92)
SEATING
PLANE
0.022 (0.56)
0.018 (0.46)
0.014 (0.36)
0.195 (4.95)
0.130 (3.30)
0.115 (2.92)
0.015 (0.38)
GAUGE
PLANE
0.014 (0.36)
0.010 (0.25)
0.008 (0.20)
0.430 (10.92)
MAX
0.005 (0.13)
MIN
0.070 (1.78)
0.060 (1.52)
0.045 (1.14)
070606-A
COMPLIANT TO JEDEC STANDARDS MS-001
CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
CORNER LEADS MAY BE CONFIGURED AS WHOLE OR HALF LEADS.
Figure 1. 8-Lead Plastic Dual In-Line Package [PDIP]
Narrow Body
(N-8)
Dimensions shown in inches and (millimeters)
5.00 (0.1968)
4.80 (0.1890)
1
5
6.20 (0.2441)
5.80 (0.2284)
4
1.27 (0.0500)
BSC
0.25 (0.0098)
0.10 (0.0040)
COPLANARITY
0.10
SEATING
PLANE
1.75 (0.0688)
1.35 (0.0532)
0.51 (0.0201)
0.31 (0.0122)
0.50 (0.0196)
0.25 (0.0099)
45°
8°
0°
0.25 (0.0098)
0.17 (0.0067)
1.27 (0.0500)
0.40 (0.0157)
COMPLIANT TO JEDEC STANDARDS MS-012-AA
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.
012407-A
8
4.00 (0.1574)
3.80 (0.1497)
Figure 2. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body
(R-8)
Dimensions shown in millimeters and (inches)
ORDERING GUIDE
Model1
OP90GPZ
OP90GS
OP90GS-REEL
OP90GS-REEL7
OP90GSZ
OP90GSZ-REEL
OP90GSZ-REEL7
1
Temperature Range
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
Package Description
8-Lead PDIP
8-Lead SOIC_N
8-Lead SOIC_N
8-Lead SOIC_N
8-Lead SOIC_N
8-Lead SOIC_N
8-Lead SOIC_N
Z = RoHS Compliant Part.
Rev. C | Page 12 of 13
Package Option
N-8
R-8
R-8
R-8
R-8
R-8
R-8
OP90
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
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
5/02—Rev. A to Rev. B
Edits to 8-Lead SOIC Package (R-8) ............................................ 12
©2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D00321-0-12/11(C)
Rev. C | Page 13 of 13
工商网监
湘ICP备2023018690号
