MAX44248AUA+ [MAXIM]
Operational Amplifier, 2 Func, 10uV Offset-Max, BICMOS, PDSO8, ROHS COMPLIANT, UMAX-8;型号: | MAX44248AUA+ |
厂家: | MAXIM INTEGRATED PRODUCTS |
描述: | Operational Amplifier, 2 Func, 10uV Offset-Max, BICMOS, PDSO8, ROHS COMPLIANT, UMAX-8 放大器 信息通信管理 光电二极管 |
文件: | 总15页 (文件大小:838K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
EVALUATION KIT AVAILABLE
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
General Description
Benefits and Features
The MAX44244/MAX44245/MAX44248 family of parts
provide ultra-precision, low-noise, zero-drift single/quad/
dual operational amplifiers featuring very low-power
operation with a wide supply range. The devices incor-
porate a patented auto-zero circuit that constantly mea-
sures and compensates the input offset to eliminate drift
over time and temperature as well as the effect of 1/f
noise. These devices also feature integrated EMI filters
to reduce high-frequency signal demodulation on the
output. The op amps operate from either a single 2.7V to
36V supply or dual 1.35V to 18V supply. The devices
are unity-gain stable with a 1MHz gain-bandwidth prod-
uct and a low 90µA supply current per amplifier.
● Reduces Power for Sensitive Precision Applications
• Low 90µA Quiescent Current per Amplifier
● Eliminates the Cost of Calibration with Increased
Accuracy with Maxim’s Patented Autozero Circuitry
• Very Low Input Voltage Offset 7.5µV (max)
• Low 30nV/NC Offset Drift (max)
● Low Noise Ideal for Sensor Interfaces and
Transmitters
• 50nV/√Hz at 1kHz
• 0.5µV
from 0.1Hz to 10Hz
P-P
● 1MHz Gain-Bandwidth Product
• EMI Suppression Circuitry
● Rail-to-Rail Output
The low offset and noise specifications and high supply
range make the devices ideal for sensor interfaces and
transmitters.
● Wide Supply for High-Voltage Front Ends
• 2.7V to 36V Supply Range
● µMAX, SO, SOT23, TSSOP Packages
The devices are available in FMAXM, SO, SOT23, and
TSSOP packages and are specified over the -40NC to
+125NC automotive operating temperature range.
Applications
Sensors Interfaces
4mA to 20mA and 0 to10V Transmitters
PLC Analog I/O Modules
Weight Scales
Ordering Information appears at end of data sheet.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
Portable Medical Devices
Typical Operating Circuit
LP+
V
REF
MAX6033
REF
I
SIG
R1
(4-20mA)
R2
MAX5216
DAC
MAX44244
R3
FLOATING
GROUND
R
SENSE
LP-
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-6367; Rev 5; 9/15
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
ABSOLUTE MAXIMUM RATINGS
V
to V ............................................................-0.3V to +40V
Operating Temperature Range........................ -40NC to +125NC
Storage Temperature ....................................... -65NC to +150NC
Junction Temperature .....................................................+150NC
Lead Temperature (soldering, 10s) ................................+300NC
Soldering Temperature (reflow) ......................................+260NC
DD
SS
Common-Mode Input Voltage........(V - 0.3V) to (V
+ 0.3V)
SS
DD
Differential Input Voltage IN_+, IN_- ......................................6V
Continuous Input Current Into Any Pin ........................... Q20mA
Output Voltage to V (OUT_) ................– 0.3V to (V
+ 0.3V)
SS
DD
Output Short-Circuit Duration (OUT_)..................................... 1s
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional opera-
tion of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
PACKAGE THERMAL CHARACTERISTICS (Note 1)
SO-8
Junction-to-Ambient Thermal Resistance (B ) ........132NC/W
TSSOP
Junction-to-Ambient Thermal Resistance (B ) ........110NC/W
JA
JA
Junction-to-Case Thermal Resistance (B )...............38NC/W
Junction-to-Case Thermal Resistance (B )...............30NC/W
JC
JC
SO-14
FMAX
Junction-to-Ambient Thermal Resistance (B ) ........120NC/W
Junction-to-Ambient Thermal Resistance (B ) .....206.3NC/W
JA
JA
Junction-to-Case Thermal Resistance (B )...............37NC/W
SOT23
Junction-to-Case Thermal Resistance (B )...............42NC/W
JC
JC
Junction-to-Ambient Thermal Resistance (B ) .....324.3NC/W
JA
Junction-to-Case Thermal Resistance (B )...............82NC/W
JC
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
ELECTRICAL CHARACTERISTICS
(V
= 10V, V = 0V, V
= V = V /2, R = 5kI to V /2, T = -40NC to +125NC, unless otherwise noted. Typical values are
DD
SS
IN+
IN-
DD
L
DD
A
at +25NC.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
POWER SUPPLY
Supply Voltage Range
V
Guaranteed by PSRR
= +25NC, V = V = V /2 - 1V
2.7
140
133
36
V
DD
T
148
100
90
Power-Supply Rejection Ratio
(Note 3)
A
IN+
IN-
DD
PSRR
dB
-40NC < T < +125NC
A
T
= +25NC
160
190
130
145
Quiescent Current Per Amplifier
(MAX4244 Only)
A
I
I
FA
FA
DD
DD
-40NC < T < +125NC
A
T
= +25NC
Quiescent Current Per Amplifier
(MAX44245/MAX44248 Only)
A
-40NC < T < +125NC
A
DC SPECIFICATIONS
V
0.05
-
V
1.5
-
SS
DD
Input Common-Mode Range
V
Guaranteed by CMRR test
V
CM
Maxim Integrated
2
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
ELECTRICAL CHARACTERISTICS (continued)
(V
= 10V, V = 0V, V
= V = V /2, R = 5kI to V /2, T = -40NC to +125NC, unless otherwise noted. Typical values are
DD
SS
IN+
IN-
DD
L
DD
A
at +25NC.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
T
1.5V
= +25NC, V
= V - 0.05V to V
-
A
CM
SS
DD
126
130
Common-Mode Rejection Ratio
(Note 3)
CMRR
dB
-40NC < T < +125NC, V
= V - 0.05V
A
CM
SS
120
to V
- 1.5V
DD
T
= +25NC
2
7.5
10
A
Input Offset Voltage (Note 3)
V
FV
nV/NC
pA
OS
-40NC < T < +125NC
A
Input Offset Voltage Drift
(Note 3)
TC V
10
30
OS
T
= +25NC
150
300
700
A
Input Bias Current (Note 3)
Input Offset Current (Note 3)
I
B
-40NC < T < +125NC
A
T
= +25NC
300
150
600
A
I
pA
OS
-40NC < T < +125NC
1400
A
T
= +25NC
140
135
A
V
V
0.5V
+ 0.5V P
SS
Open-Loop Gain (Note 3)
Output Short-Circuit Current
A
PV -
dB
VOL
OUT
DD
-40NC < T < +125NC
A
To V
or V , noncontinuous
40
mA
DD
SS
T
= +25NC
80
110
50
V
V
-
A
DD
-40NC < T < +125NC
OUT
A
Output Voltage Swing
mV
T
= +25NC
V
-
A
OUT
V
-40NC < T < +125NC
75
SS
A
AC SPECIFICATIONS
Input Voltage-Noise Density
Input Voltage Noise
e
f = 1kHz
50
500
0.1
1
nV/√Hz
N
0.1Hz < f < 10Hz
f = 1kHz
nV
P-P
Input Current-Noise Density
Gain-Bandwidth Product
Slew Rate
i
pA/√Hz
MHz
V/Fs
pF
N
GBW
SR
A
= 1V/V, V
= 2V
P-P
0.7
400
V
OUT
Capacitive Loading
C
No sustained oscillation, A = 1V/V
V
L
Total Harmonic Distortion Plus
Noise
THD+N
V
= 2V , A = +1V/V, f = 1kHz
-100
dB
OUT
P-P
V
f = 400MHz
f = 900MHz
f = 1800MHz
f = 2400MHz
75
78
80
90
EMI Rejection Ratio
EMIRR
V
= 100mV
dB
RF_PEAK
Maxim Integrated
3
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
ELECTRICAL CHARACTERISTICS
(V
= 30V, V = 0V, V
= V = V /2, R = 5kI to V /2, T = -40NC to +125NC, unless otherwise noted. Typical values are
DD
SS
IN+
IN-
DD
L
DD
A
at +25NC.) (Note 2)
PARAMETER
POWER SUPPLY
SYMBOL
CONDITIONS
MIN
TYP
100
90
MAX
UNITS
T
= +25NC
160
190
130
145
Quiescent Current Per Amplifier
(MAX44244 Only)
A
I
I
FA
FA
DD
DD
-40NC < T < +125NC
A
T
= +25NC
Quiescent Current Per Amplifier
(MAX44245/MAX44248 Only)
A
-40NC < T < +125NC
A
DC SPECIFICATIONS
V
0.05
-
V
1.5
-
SS
DD
Input Common-Mode Range
V
Guaranteed by CMRR test
V
CM
T
1.5V
= +25NC, V
= V - 0.05V to V
-
A
CM
SS
DD
130
126
140
2
Common-Mode Rejection Ratio
(Note 3)
CMRR
dB
-40NC < T < +125NC, V
to V
= V - 0.05V
A
CM
SS
- 1.5V
DD
T
= +25NC
7.5
10
A
Input Offset Voltage (Note 3)
V
FV
nV/°C
pA
OS
-40NC < T < +125NC
A
Input Offset Voltage Drift
(Note 3)
TC V
10
30
OS
T
= +25NC
150
300
700
600
A
Input Bias Current (Note 3)
Input Offset Current (Note 3)
I
B
-40NC < T < +125NC
A
T
= +25NC
300
150
40
A
I
pA
OS
-40NC < T < +125NC
1400
A
T
= +25NC
146
140
V
+ 0.5V PV
A
SS
OUT
Open-Loop Gain (Note 3)
Output Short-Circuit Current
A
dB
VOL
PV
- 0.5V
-40NC < T < +125NC
DD
A
To V
or V , noncontinuous
mA
DD
SS
T
= +25NC
200
270
140
220
V
V
-
A
DD
-40NC < T < +125NC
OUT
A
Output Voltage Swing
mV
T
= +25NC
V
-
A
OUT
V
-40NC < T < +125NC
SS
A
AC SPECIFICATIONS
Input Voltage-Noise Density
Input Voltage Noise
e
f = 1kHz
50
500
0.1
1
nV/√Hz
N
0.1Hz < f < 10Hz
f = 1kHz
nV
P-P
Input Current-Noise Density
Gain-Bandwidth Product
i
pA/√Hz
N
GBW
MHz
Maxim Integrated
4
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
ELECTRICAL CHARACTERISTICS (continued)
(V
= 30V, V = 0V, V
= V = V /2, R = 5kI to V /2, T = -40NC to +125NC, unless otherwise noted. Typical values are
DD
SS
IN+
IN-
DD
L
DD
A
at +25NC.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
0.7
MAX
UNITS
V/Fs
pF
Slew Rate
SR
A
= 1V/V, V
= 2V
V
OUT P-P
Capacitive Loading
C
No sustained oscillation, A = 1V/V
400
L
V
Total Harmonic Distortion Plus
Noise
THD+N
V
= 2V , A = +1V/V, f = 1kHz
-100
dB
OUT
P-P
V
f = 400MHz
f = 900MHz
f = 1800MHz
f = 2400MHz
75
78
80
90
V
=
RF_PEAK
EMI Rejection Ratio
EMIRR
dB
100mV
Note 2: All devices are 100% production tested at T = +25NC. Temperature limits are guaranteed by design.
A
Note 3: Guaranteed by design.
Note 4: At IN+ and IN-. Defined as 20log (V
/δV ).
OS
RF_PEAK
Typical Operating Characteristics
(V= 10V, V = 0V, V
= V = V /2, R = 5kω to V /2. Typical values are at T = +25°C.)
DD SS IN+
IN-
DD
L
DD
A
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
INPUT OFFSET VOLTAGE HISTOGRAM
INPUT OFFSET VOLTAGE DRIFT
45
40
35
30
25
20
15
10
5
35
30
25
20
15
10
5
100
98
96
94
92
90
88
86
84
82
80
0
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
INPUT OFFSET VOLTAGE (µV)
4
5
6
7
8
9
10 11 12 13 14
0
10
20
30
40
INPUT OFFSET VOLTAGE DRIFT (nV/°C)
SUPPLY VOLTAGE (V)
Maxim Integrated
5
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Typical Operating Characteristics (continued)
(V
= 10V, V = 0V, V
= V = V /2, R = 5kω to V /2. Typical values are at T = +25°C.)
DD
SS
IN+
IN-
DD
L
DD
A
INPUT OFFSET VOLTAGE
vs. COMMON-MODE VOLTAGE
INPUT OFFSET VOLTAGE
VS. TEMPERATURE
SUPPLY CURRENT
vs. TEMPERATURE
2
1
3
2
100
98
96
94
92
90
88
86
84
82
80
1
0
-1
-2
-3
-4
0
-1
-2
-3
-4
-5
-6
-4
-2
0
2
4
6
-50 -25
0
25
50
75 100 125
-50 -25
0
25
50
75 100 125
COMMON-MODE VOLTAGE (V)
TEMPERATURE (°C)
TEMPERATURE (°C)
INPUT BIAS CURRENT
VS. COMMON-MODE VOLTAGE
INPUT BIAS CURRENT
vs. TEMPERATURE
180
160
140
120
100
80
800
600
400
200
0
60
40
-200
-400
20
0
0
2
4
6
8
10
-50 -25
0
25
50
75 100 125
COMMON-MODE VOLTAGE (V)
TEMPERATURE (°C)
COMMON-MODE REJECTION RATIO
vs. FREQUENCY
COMMON-MODE REJECTION RATIO
vs. TEMPERATURE
-100
-105
-110
-115
-120
-125
-130
-135
0
-20
-40
-60
-80
-100
-120
-140
-50 -25
0
25
50
75 100 125
10
100
1k
10k
100k
1M
TEMPERATURE (°C)
FREQUENCY (Hz)
Maxim Integrated
6
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Typical Operating Characteristics (continued)
(V
= 10V, V = 0V, V
= V = V /2, R = 5kω to V /2. Typical values are at T = +25°C.)
DD
SS
IN+
IN-
DD
L
DD
OUTPUT VOLTAGE HIGH
vs. TEMPERATURE
A
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
OUTPUT VOLTAGE LOW
vs. TEMPERATURE
0
80
70
60
50
40
30
60
50
40
30
20
10
0
-20
-40
-60
-80
-100
-120
-140
-160
20
10
0
10
100
1k
10k
100k
1M
-50 -25
0
25
50
75 100 125
-50 -25
0
25
50
75 100 125
FREQUENCY (Hz)
TEMPERATURE (°C)
TEMPERATURE (°C)
OUTPUT VOLTAGE HIGH
vs. SOURCE CURRENT
OUTPUT VOLTAGE LOW
vs. SINK CURRENT
1000
100
10
1000
100
10
1
1
0.1
1
10
0.1
1
10
SOURCE CURRENT (mA)
SINK CURRENT (mA)
INPUT VOLTAGE NOISE
vs. FREQUENCY
INPUT VOLTAGE 0.1Hz TO 10Hz NOISE
MAX44248 toc17
200
180
160
140
120
100
80
400nV/div
60
40
20
0
1s/div
10
100
1k
10k
100k
FREQUENCY (Hz)
Maxim Integrated
7
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Typical Operating Characteristics (continued)
(V
= 10V, V = 0V, V
= V = V /2, R = 5kω to V /2. Typical values are at T = +25°C.)
DD
SS
IN+ IN- DD L DD A
INPUT CURRENT NOISE
vs. FREQUENCY
LARGE-SIGNAL GAIN vs. FREQUENCY
SMALL-SIGNAL GAIN vs. FREQUENCY
140
120
100
80
140
120
100
80
10
9
8
7
6
5
4
3
2
1
0
60
60
40
40
20
20
0
0
-20
-40
-20
-40
0.1
1
10 100 1k
FREQUENCY (Hz)
10k 100k 1M
0.1
1
10 100 1k
FREQUENCY (Hz)
10k 100k 1M
10
100
1k
10k
100k
FREQUENCY (Hz)
LARGE-SIGNAL STEP RESPONSE
SMALL-SIGNAL STEP RESPONSE
MAX44248 toc22
MAX44248 toc21
V
IN
2V/div
V
IN
100mV/div
V
OUT
V
OUT
50mV/div
500mV/div
4µs/div
4µs/div
TOTAL HARMONIC DISTORTION
vs. FREQUENCY
POWER-UP TIME
MAX44248 toc23
0
-20
V
DD
10V/div
-40
R
= 1kI
LOAD
-60
R
= 600I
LOAD
-80
V
OUT
2V/div
-100
-120
-140
R
= 5kI
LOAD
10
100
1k
10k
100k
20µs/div
FREQUENCY (Hz)
Maxim Integrated
8
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Typical Operating Characteristics (continued)
(V
= 10V, V = 0V, V
SS
= V = V /2, R = 5kω to V /2. Typical values are at T = +25°C.)
DD
IN+
IN-
DD
L
DD
A
OUTPUT STABILITY
vs. CAPACITIVE LOAD
OUTPUT STABILITY
vs. ISOLATION RESISTANCE
10k
1k
10k
1k
UNSTABLE
STABLE
100
10
100
10
1
STABLE
UNSTABLE
1
100
1000
10,000
100,000
100
1000
10,000
100,000
CAPACITIVE LOAD (pF)
CAPACITIVE LOAD (pF)
OUTPUT IMPEDANCE
vs. FREQUENCY
CROSSTALK vs. FREQUENCY
0
-20
100
90
80
70
60
50
40
30
20
10
0
-40
-60
-80
-100
-120
-140
100
1k
10k
100k
1M
100
1k
10k
100k
1M
FREQUENCY (Hz)
FREQUENCY (Hz)
EMIRR vs. FREQUENCY
120
100
80
60
40
20
0
10
100
1,000
10,000
FREQUENCY (MHz)
Maxim Integrated
9
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Pin Configurations
TOP VIEW
+
OUTA
1
2
3
5
4
V
DD
+
N.C.
INA-
INA+
1
2
3
4
8
7
6
5
N.C.
MAX44244
V
DD
V
SS
MAX44244
OUTA
N.C.
V
SS
INA+
INA-
µMAX
SOT23
+
+
OUTA
INA-
1
2
3
4
5
6
7
14 OUTD
OUTA
INA-
1
2
3
4
5
6
7
14 OUTD
13 IND-
12 IND+
13 IND-
12 IND+
INA+
INA+
MAX44245
MAX44245
V
11
V
SS
DD
V
11 V
SS
DD
INB+
INB-
10 INC+
INB+
INB-
10 INC+
9
8
INC-
9
8
INC-
OUTB
OUTC
OUTB
OUTC
TSSOP
SO-14
+
OUTA
INA-
1
2
3
4
8
7
6
5
V
DD
+
OUTA
1
2
3
4
8
7
6
5
V
DD
MAX44248
OUTB
INB-
INA-
INA+
OUTB
INB-
MAX44248
INA+
V
INB+
SS
µMAX
V
SS
INB+
SO-8
Maxim Integrated
10
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Pin Description
PIN
MAX44245
MAX44244
MAX44248
NAME
FUNCTION
SOT23
µMAX
6
SO-14
TSSOP
SO-8
µMAX
1
1
1
11
3
1
11
3
1
4
OUTA
Channel A Output
2
4
4
V
Negative Supply Voltage
Channel A Positive Input
Channel A Negative Input
Positive Supply Voltage
Channel B Positive Input
Channel B Negative Input
Channel B Output
SS
3
3
3
3
INA+
INA-
4
2
2
2
2
2
5
7
4
4
8
8
V
DD
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
5
5
5
5
INB+
INB-
6
6
6
6
7
7
7
7
OUTB
OUTC
INC-
8
8
—
—
—
—
—
—
—
—
—
—
—
—
Channel C Output
9
9
Channel C Negative Input
Channel C Positive Input
Channel D Positive Input
Channel D Negative Input
Channel D Output
10
12
13
14
10
12
13
14
INC+
IND+
IND-
OUTD
No Connection. Not internally
connected.
—
1, 5, 8
—
—
—
—
N.C.
Detailed Description
Applications Information
The MAX44244/MAX44245/MAX44248 are high-precision
amplifiers with less than 2FV (typ) input-referred
offset and low input voltage-noise density at 10Hz.
1/f noise, in fact, is eliminated to improve the performance
in low-frequency applications. These characteristics are
achieved through an auto-zeroing technique that cancels
the input offset voltage and 1/f noise of the amplifier.
The devices feature ultra-high precision operational
amplifiers with a high supply voltage range designed
for load cell, medical instrumentation, and precision
instrument applications.
4–20mA Current-Loop Communication
Industrial environments typically have a large amount of
broadcast electromagnetic interference (EMI) from high-
voltage transients and switching motors. This combined
with long cables for sensor communication leads to
high-voltage noise on communication lines. Current-Loop
communication is resistant to this noise because the EMI
induced current is low. This configuration also allows for
low-power sensor applications to be powered from the
communication lines.
External Noise Suppression in EMI Form
These devices have input EMI filters to prevent effects
of radio frequency interference on the output. The EMI
filters comprise passive devices that present significant
higher impedance to higher frequency signals. See the
EMIRR vs. Frequency graph in the Typical Operating
Characteristics section for details.
The Typical Operating Circuit shows how the device can
be used to make a current loop driver.
High Supply Voltage Range
The devices feature 90µA current consumption per chan-
nel and a voltage supply range from either 2.7V to 36V
single supply or 1.35V to 18V split supply.
The circuit uses low-power components such as the
MAX44244 op amp, the 16-bit MAX5216 DAC, and the
high-precision 60µA-only MAX6033 reference. In this
Maxim Integrated
11
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
circuit, both the DAC and the reference are referred to
a high-accuracy internal oscillator that requires no
external components.
the local ground. The MAX44244 op-amp inputs are
capable of swinging to the negative supply (which is the
local ground in this case). R3 acts as a current mirror with
Layout Guidelines
The MAX44244/MAX44245/MAX44248 feature ultra-low
input offset voltage and noise. Therefore, to get optimum
performance follow the layout guidelines.
R
. Therefore, if R
= 50Ω (i.e. 20mA will drop
SENSE
SENSE
1V) and if the current through R3 is 10µA when I
is
OUT
20mA (0.05% error) then R3 = 100kΩ. R1 is chosen along
with the reference voltage to provide the 4mA offset. R2
= 512kΩ for 20mA full scale or R2 = 614kΩ for 20% over-
Avoid temperature tradients at the junction of two
dissimilar metals. The most common dissimilar metals
used on a PCB are solder-to-component lead and
solder-to-board trace. Dissimilar metals create a local
thermocouple. A variation in temperature across the
board can cause an additional offset due to Seebeck
effect at the solder junctions. To minimize the Seebeck
effect, place the amplifier away from potential heat
sources on the board, if possible. Orient the resistors
such that both the ends are heated equally. It is a good
practice to match the input signal path to ensure that the
type and number of thermoelectric juntions remain the
same. For example, consider using dummy 0ω resistors
oriented in such a way that the thermoelectric source, due
to the real resistors in the signal path, are cancelled. It is
recommended to flood the PCB with ground plane. The
ground plane ensures that heat is distributed uniformly
reducing the potential offset voltage degradation due to
Seebeck effect.
range. R
is ratiometric with R3, R1 independently
SENSE
sets the offset current and R2 independently sets the
DAC scaling.
Driving High-Performance ADCs
The MAX44244/MAX44245/MAX44248’s low input offset
voltage and low noise make these amplifiers ideal for
ADC buffering. Weight scale applications require a low-
noise, precision amplifier in front of an ADC. Figure 1
details an example of a load cell and amplifier driven
from the same 5V supply, along with a 16-bit delta sigma
ADC such as the MAX11205.
The MAX11205 is an ultra-low-power (< 300FA, max
active current), high-resolution, serial output ADC. It
provides the highest resolution per unit power in the
industry and is optimized for applications that require
very high dynamic range with low power such as sensors
on a 4–20mA industrial control loop. The devices provide
5V
5V
½ MAX44248
AMP A
V
DD
5V
MICRO-
CONTROLLER
R
R
F
V
DD
SCLK
RDY/DOUT
MAX11205
SCK
V
V
IN+
IN-
MISO
R
G
F
V
SS
5V
V
SS
AMP B
½ MAX44248
Figure 1. Weight Application
Maxim Integrated
12
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Chip Information
Package Information
For the latest package outline information and land patterns (foot-
prints), go to www.maximintegrated.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but the
drawing pertains to the package regardless of RoHS status.
PROCESS: BiCMOS
Ordering Information
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
PIN-
TOP
PART
TEMP RANGE
PACKAGE MARK
21-0057
21-0041
21-0036
21-0041
21-0066
90-0174
90-0096
90-0092
90-0112
90-0113
5 SOT23
8 SO
U5+1
S8+4
MAX44244AUK+
MAX44244AUA+
MAX44245ASD+
MAX44245AUD+
MAX44248AUA+
MAX44248ASA+
-40°C to +125°C 5 SOT23
-40°C to +125°C 8 µMAX
-40°C to +125°C 14 SO
-40°C to +125°C 14 TSSOP
-40°C to +125°C 8 µMAX
-40°C to +125°C 8 SO
AFMR
—
8 µMAX
14 SO
U8+1
—
—
S14M+4
U14M+1
—
14 TSSOP
—
+Denotes a lead(Pb)-free/RoHS-compliant package.
Maxim Integrated
13
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
DESCRIPTION
CHANGED
0
7/12
Initial release
—
Added the MAX44244/MAX44245 to data sheet. Updated the Electrical
Characteristics, Absolute Maximum Ratings, Pin Description, and Pin
Configurations.
1
6/13
1–13
Released the MAX44244 for introduction. Revised the Electrical
Characteristics
2
9/13
2–5, 13
3
4
5
6/14
12/14
9/15
Corrected Figure 1 and Package Information
Updated Benefits and Features section
Updated Typical Operating Circuit
12, 13
1
1
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent
licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and
max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000
14
©
2015 Maxim Integrated
The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc.
MAX44244/MAX44245/MAX44248
36V, Precision, Low-Power, 90µA,
Single/Quad/Dual Op Amps
Maxim Integrated
15
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