19-4194; Rev 6; 9/09
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
The MAX410/MAX412/MAX414 single/dual/quad op
amps set a new standard for noise performance in
high-speed, low-voltage systems. Input voltage-noise
density is guaranteed to be less than 2.4nV/√Hz at
1kHz. A unique design not only combines low noise
with ±5V operation, but also consumes 2.5mA supply
current per amplifier. Low-voltage operation is guaranteed with an output voltage swing of 7.3VP-P into 2kΩ
from ±5V supplies. The MAX410/MAX412/MAX414 also
operate from supply voltages between ±2.4V and ±5V
for greater supply flexibility.
Unity-gain stability, 28MHz bandwidth, and 4.5V/µs
slew rate ensure low-noise performance in a wide variety of wideband and measurement applications. The
MAX410/MAX412/MAX414 are available in DIP and SO
packages in the industry-standard single/dual/quad op
amp pin configurations. The single comes in an ultrasmall TDFN package (3mm 3mm).
Applications
Features
o Voltage Noise: 2.4nV/√Hz (max) at 1kHz
o 2.5mA Supply Current Per Amplifier
o Low Supply Voltage Operation: ±2.4V to ±5V
o 28MHz Unity-Gain Bandwidth
o 4.5V/µs Slew Rate
o 250µV (max) Offset Voltage (MAX410/MAX412)
o 115dB (min) Voltage Gain
o Available in an Ultra-Small TDFN Package
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX410CPA
0°C to +70°C
8 Plastic DIP
MAX410BCPA
0°C to +70°C
8 Plastic DIP
MAX410CSA
0°C to +70°C
8 SO
MAX410BCSA
0°C to +70°C
8 SO
MAX410EPA
-40°C to +85°C
8 Plastic DIP
Low-Noise Frequency Synthesizers
MAX410BEPA
-40°C to +85°C
8 Plastic DIP
Infrared Detectors
MAX410ESA
-40°C to +85°C
8 SO
High-Quality Audio Amplifiers
MAX410BESA
-40°C to +85°C
8 SO
MAX410ETA
-40°C to +85°C
8 TDFN-EP*
Ultra Low-Noise Instrumentation Amplifiers
Bridge Signal Conditioning
MAX410MSA/PR
-55°C to +125°C
8 SO**
MAX410MSA/PR-T
-55°C to +125°C
8 SO**
*EP = Exposed pad. Top Mark—AGQ.
**Contact factory for availability.
Typical Operating Circuit
Ordering Information continued at end of data sheet.
Pin Configurations
1kΩ*
42.2kΩ**
1%
TOP VIEW
200Ω
1%
2
1
-IN
42.2kΩ
1%
3
200Ω
1%
6
1/2 MAX412
7
5
1/2 MAX412
+IN
OUT
NULL
1
IN-
2
7
V+
IN+
3
6
OUT
V- 4
5
N.C.
8
NULL
8
V+
DIP/SO/TDFN
*TRIM FOR GAIN.
**TRIM FOR COMMON-MODE REJECTION.
LOW-NOISE INSTRUMENTATION AMPLIFIER
MAX410
OUT1
1
IN1-
2
7
OUT2
IN1+
3
6
IN2-
V- 4
5
IN2+
MAX412
DIP/SO
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim's website at www.maxim-ic.com.
1
MAX410/MAX412/MAX414
General Description
MAX410/MAX412/MAX414
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
ABSOLUTE MAXIMUM RATINGS
Supply Voltage .......................................................................12V
Differential Input Current (Note 1) ....................................±20mA
Input Voltage Range........................................................V+ to VCommon-Mode Input Voltage ..............(V+ + 0.3V) to (V- - 0.3V)
Short-Circuit Current Duration....................................Continuous
Continuous Power Dissipation (TA = +70°C)
MAX410/MAX412
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C) ...727mW
8-Pin SO (derate 5.88mW/°C above +70°C)................471mW
8-Pin TDFN (derate 18.5mW/°C above +70°C) .........1482mW
MAX414
14-Pin Plastic DIP (derate 10.00mW/°C above +70°C)800mW
14-Pin SO (derate 8.33mW/°C above +70°C)..............667mW
Operating Temperature Ranges:
MAX41_C_ _ .......................................................0°C to +70°C
MAX41_E_ _.....................................................-40°C to +85°C
MAX41_M_ _ ..................................................-55°C to +125°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1: The amplifier inputs are connected by internal back-to-back clamp diodes. In order to minimize noise in the input stage, currentlimiting resistors are not used. If differential input voltages exceeding ±1.0V are applied, limit input current to 20mA.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation 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.
ELECTRICAL CHARACTERISTICS
(V+ = 5V, V- = -5V, TA = +25°C, unless otherwise noted.)
PARAMETER
Input Offset Voltage
Input Bias Current
SYMBOL
VOS
TYP
MAX
MAX410, MAX410B, MAX412, MAX412B
CONDITIONS
MIN
±120
±250
MAX414, MAX414B
±150
±320
UNITS
µV
IB
±80
±150
nA
IOS
±40
±80
nA
Differential Input Resistance
RIN(Diff)
20
kΩ
Common-Mode Input Resistance
RIN(CM)
40
MΩ
CIN
4
pF
Input Offset Current
Input Capacitance
MAX410, MAX412,
MAX414
Input Noise-Voltage Density
Input Noise-Current Density
Common-Mode Input Voltage
en
in
MAX410B, MAX412B,
MAX414B
10Hz
7
1000Hz (Note 2)
1.5
2.4
1000Hz (Note 2)
2.4
4.0
fO = 10Hz
2.6
fO = 1000Hz
1.2
VCM
nV√Hz
pA√Hz
±3.5
+3.7/
-3.8
V
115
130
dB
dB
Common-Mode Rejection Ratio
CMRR
VCM = ±3.5V
Power-Supply Rejection Ratio
PSRR
VS = ±2.4V to ±5.25V
96
103
RL = 2kΩ, VO = ±3.6V
115
122
RL = 600Ω, VO = ±3.5V
110
120
RL = 2kΩ
+3.6
-3.7
+3.7/
-3.8
V
35
mA
Large-Signal Gain
AVOL
Output Voltage Swing
VOUT
Short-Circuit Output Current
Slew Rate
Unity-Gain Bandwidth
ISC
dB
SR
10kΩ || 20pF load
4.5
V/µs
GBW
10kΩ || 20pF load
28
MHz
Settling Time
tS
To 0.1%
1.3
µs
Channel Separation
CS
fO = 1kHz
135
dB
2
_______________________________________________________________________________________
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
MAX410/MAX412/MAX414
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 5V, V- = -5V, TA = +25°C, unless otherwise noted.)
PARAMETER
SYMBOL
Operating Supply-Voltage Range
VS
Supply Current
IS
CONDITIONS
MIN
TYP
±2.4
Per amplifier
MAX
UNITS
±5.25
V
2.7
mA
TYP
MAX
UNITS
±150
±350
µV
2.5
ELECTRICAL CHARACTERISTICS
(V+ = 5V, V- = -5V, TA = 0°C to +70°C, unless otherwise noted.)
PARAMETER
Input Offset Voltage
SYMBOL
CONDITIONS
MIN
VOS
Offset Voltage Tempco
Input Bias Current
∆VOS/∆T
Over operating temperature range
±1
µV/°C
IB
±100
±200
nA
Input Offset Current
IOS
±80
±150
nA
Common-Mode Input Voltage
VCM
±3.5
+3.7/
-3.8
V
105
121
dB
dB
Common-Mode Rejection Ratio
CMRR
VCM = ±3.5V
Power-Supply Rejection Ratio
PSRR
VS = ±2.4V to ±5.25V
90
97
RL = 2kΩ, VO = ±3.6V
110
120
RL = 600Ω, VO = ±3.5V
90
119
±3.5
+3.7/
-3.6
Large-Signal Gain
AVOL
Output Voltage Swing
VOUT
Supply Current
IS
RL = 2kΩ
Per amplifier
dB
V
3.3
mA
MAX
UNITS
ELECTRICAL CHARACTERISTICS
(V+ = 5V, V- = -5V, TA = -40°C to +85°C, unless otherwise noted.) (Note 3)
PARAMETER
Input Offset Voltage
SYMBOL
VOS
Offset Voltage Tempco
Input Bias Current
∆VOS/∆T
CONDITIONS
MIN
TYP
MAX410, MAX410B, MAX412, MAX412B
±200
±400
MAX414, MAX414B
±200
±450
Over operating temperature range
±1
µV
µV/°C
IB
±130
±350
nA
Input Offset Current
IOS
±100
±200
nA
Common-Mode Input Voltage
VCM
±3.5
+3.7/
-3.6
V
Common-Mode Rejection Ratio
CMRR
VCM = ±3.5V
105
120
dB
Power-Supply Rejection Ratio
PSRR
VS = ±2.4V to ±5.25V
90
94
dB
Large-Signal Gain
AVOL
RL = 2kΩ, VO = ±3.6V
110
118
RL = 600Ω, VO = +3.4V to -3.5V
90
114
Output Voltage Swing
VOUT
±3.5
+3.7/
-3.6
Supply Current
IS
RL = 2kΩ
Per amplifier
dB
V
3.3
mA
_______________________________________________________________________________________
3
MAX410/MAX412/MAX414
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
ELECTRICAL CHARACTERISTICS (MAX410 only)
(V+ = 5V, V- = -5V, TA = -55°C to +125°C, unless otherwise noted.)
PARAMETER
Input Offset Voltage
Offset Voltage Tempco
Input Bias Current
Input Offset Current
Common-Mode Input Voltage
SYMBOL
CONDITIONS
MIN
VOS
∆VOS/∆T
Over operating temperature range
TYP
MAX
±200
±400
±1
UNITS
µV
µV/°C
IB
±130
±350
nA
IOS
±100
±200
nA
VCM
±3.5
+3.7/
-3.6
V
Common-Mode Rejection Ratio
CMRR
VCM = ±3.5V
105
120
dB
Power-Supply Rejection Ratio
PSRR
VS = ±2.4V to ±5.25V
90
94
dB
Large-Signal Gain
AVOL
RL = 2kΩ, VO = ±3.5V
110
118
RL = 600Ω, VO = +3.4V to -3.5V
90
114
Output Voltage Swing
VOUT
±3.5
+3.7/
-3.6
Supply Current
IS
RL = 2kΩ
Per amplifier
dB
V
3.3
Note 2: Guaranteed by design.
Note 3: All TDFN devices are 100% tested at TA = +25°C. Limits over temperature for thin TDFNs are guaranteed by design.
4
_______________________________________________________________________________________
mA
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
VS = ±5V
TA = +25°C
CURRENT-NOISE DENSITY (pA/√Hz)
10
45
40
35
UNITS (%)
VS = ±5V
TA = +25°C
1kHz VOLTAGE NOISE DISTRIBUTION
50
100
1k
20
5
1/F CORNER = 220Hz
10k
0
1
10
FREQUENCY (Hz)
100
1k
1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9
INPUT-REFERRED VOLTAGE NOISE (nV/√Hz)
10k
FREQUENCY (Hz)
0.1Hz TO 10Hz VOLTAGE NOISE
WIDEBAND NOISE DC TO 20kHz
MAX410-14 toc04
MAX410-14 toc05
100nV/div
(INPUT-REFERRED)
2µV/div
(INPUT-REFERRED)
1s/div
0.2ms/div
80
60
40
20
0
SOURCE
40
30
MAX410-14 toc07
VS = ±5V
SINK
20
10
-20
20
60
TEMPERATURE (°C)
100
140
VS = ±5V
RL = 2kΩ
9
8
7
6
5
4
3
2
1
0
0
-60
10
OUTPUT VOLTAGE SWING (VP-P)
OPEN-LOOP GAIN (dB)
VS = ±5V
RL = 2kΩ
100
50
SHORT-CIRCUIT OUTPUT CURRENT (mA)
140
120
OUTPUT VOLTAGE SWING
vs. TEMPERATURE
SHORT-CIRCUIT OUTPUT CURRENT
vs. TEMPERATURE
MAX410-14 toc06
OPEN-LOOP GAIN
vs. TEMPERATURE
MAX410-14 toc08
10
25
10
1
1
30
15
1/F CORNER = 90Hz
1
MAX410-14 toc03
10
MAX410-14 toc01
VOLTAGE-NOISE DENSITY (nV/√Hz)
100
CURRENT-NOISE DENSITY
vs. FREQUENCY
MAX410-14 toc02
VOLTAGE-NOISE DENSITY
vs. FREQUENCY
-60
-20
20
60
TEMPERATURE (°C)
100
140
-60
-20
20
60
100
140
TEMPERATURE (°C)
_______________________________________________________________________________________
5
MAX410/MAX412/MAX414
Typical Operating Characteristics
(TA == +25°C,
(V+
5V, V- =unless
-5V, Totherwise
noted.)
unless otherwise noted.)
A = +25°C,
Typical Operating Characteristics (continued)
(V+ = 5V, V- = -5V, TA = +25°C, unless otherwise noted.)
SLEW RATE (V/µs)
8
3
2
1
7
6
5
4
3
2
50
MAX410-14 toc11
VS = ±5V
RL = 10kΩ II 20pF
9
UNITY-GAIN BANDWIDTH (MHz)
EACH AMPLIFIER
VS = ±5V
4
SUPPLY CURRENT (mA)
10
MAX410-14 toc09
5
UNITY-GAIN BANDWIDTH
vs. TEMPERATURE
SLEW RATE
vs. TEMPERATURE
MAX410-14 toc10
SUPPLY CURRENT
vs. TEMPERATURE
VS = ±5V
RL = 10kΩ II 20pF
40
30
20
10
1
0
0
0
-20
20
60
100
-60
140
-20
TEMPERATURE (°C)
20
60
100
-60
140
-20
LARGE-SIGNAL TRANSIENT RESPONSE
INPUT
3V/div
GND
INPUT
50mV/div
GND
OUTPUT
3V/div
GND
OUTPUT
50mV/div
GND
1µs/div
WIDEBAND VOLTAGE NOISE
(0.1Hz TO FREQUENCY INDICATED)
VS = ±5V
TA = +25°C
MAX410-14 toc15
RS
RS
1k
100
@10Hz
10
NLY
EO
@1kHz
RS
IS
NO
1
10k
100k
BANDWIDTH (Hz)
1M
10M
10k
RS
1k
100
@10Hz
10
@1kHz
R
LY
ON
ISE
O
N
S
1
VS = ±5V
TA = +25°C
VS = ±5V
TA = +25°C
0.1
0.1
0.01
6
TOTAL NOISE DENSITY
vs. UNMATCHED SOURCE RESISTANCE
TOTAL NOISE DENSITY (nV/√Hz)
0.1
TOTAL NOISE DENSITY (nV/√Hz)
MAX410-14 toc14
1
10k
1
140
200ns/div
AV = +1, RF = 499Ω, RL = 2kΩ II 20pF, VS = ±5V, TA = +25°C
TOTAL NOISE DENSITY
vs. MATCHED SOURCE RESISTANCE
10
100
MAX410-14 toc13
AV = +1, RF = 499Ω, RL = 2kΩ II 20pF, VS = ±5V, TA = +25°C
1k
60
SMALL-SIGNAL TRANSIENT RESPONSE
MAX410-14 toc12
100
20
TEMPERATURE (°C)
TEMPERATURE (°C)
MAX410-14 toc16
-60
RMS VOLTAGE NOISE (µV)
MAX410/MAX412/MAX414
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
10
100
1k
10k
100k
MATCHED SOURCE RESISTANCE (Ω)
1M
1
10
100
1k
10k
100k
UNMATCHED SOURCE RESISTANCE (Ω)
_______________________________________________________________________________________
1M
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
RS
2kΩ
35
-91
-94
CL
30
25
20
AV = -1, RS = 2kΩ
15
10
-97
150
VS = ±5V
TA = +25°C
140
MAX410-14 toc19
40
OVERSHOOT (%)
THD+N (dB)
VIN
7VP-P
VS = ±5V
TA = +25°C
30pF
45
CHANNEL SEPARATION (dB)
-88
50
MAX410-14 toc18
VS = ±5V
TA = +25°C
499Ω
MAX410-14 toc17
-85
MAX412/MAX414
CHANNEL SEPARATION vs. FREQUENCY
PERCENTAGE OVERSHOOT
vs. CAPACITIVE LOAD
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
130
120
500Ω
500Ω
V01
110
1kΩ
100
10Ω
V02
90
AV = -10, RS = 200Ω
5
CHANNEL SEPARATION = 20 logIN
80
0
20
100
10k
1k
50k
1
10
FREQUENCY (Hz)
100
1000
10,000
MAX410-14 toc20
120
GAIN
40
45
30
-45
PHASE
-90
-135
0
-45
GAIN
10
0
-90
-10
-20
-135
PHASE
-30
20
-180
0
-225
-50
-270
0.001
0.1
10
1,000
100,000
0.0001
0.01
1
100
10,000
FREQUENCY (kHz)
-60
-20
MAX410-14 toc21
20
VOLTAGE GAIN (dB)
60
40
0
80
1000
GAIN AND PHASE vs. FREQUENCY
90
PHASE (DEGREES)
VOLTAGE GAIN (dB)
100
100
FREQUENCY (kHz)
GAIN AND PHASE vs. FREQUENCY
140
10
1
CAPACITANCE LOAD (pF)
-40
PHASE (DEGREES)
-100
-180
-225
1
10
100
FREQUENCY (MHz)
_______________________________________________________________________________________
7
MAX410/MAX412/MAX414
Typical Operating Characteristics (continued)
(V+ = 5V, V- = -5V, TA = +25°C, unless otherwise noted.)
MAX410/MAX412/MAX414
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
Applications Information
The MAX410/MAX412/MAX414 provide low voltagenoise performance. Obtaining low voltage noise from a
bipolar op amp requires high collector currents in the
input stage, since voltage noise is inversely proportional to the square root of the input stage collector current.
However, op amp current noise is proportional to the
square root of the input stage collector current, and the
input bias current is proportional to the input stage collector current. Therefore, to obtain optimum low-noise
performance, DC accuracy, and AC stability, minimize
the value of the feedback and source resistance.
Total Noise Density vs. Source Resistance
The standard expression for the total input-referred
noise of an op amp at a given frequency is:
e t = en2 +(Rp +Rn )2 in2 + 4kT (Rp +Rn )
where:
Rn = Inverting input effective series resistance
Rp = Noninverting input effective series resistance
becomes the dominant term, eventually making the
voltage noise contribution from the MAX410/MAX412/
MAX414 negligible. As the source resistance is further
increased, current noise becomes dominant. For example, when the equivalent source resistance is greater
than 3kΩ at 1kHz, the current noise component is larger than the resistor noise. The graph of Total Noise
Density vs. Matched Source Resistance in the Typical
Operating Characteristics shows this phenomenon.
Optimal MAX410/MAX412/MAX414 noise performance
and minimal total noise achieved with an equivalent
source resistance of less than 10kΩ.
Voltage Noise Testing
RMS voltage-noise density is measured with the circuit
shown in Figure 2, using the Quan Tech model 5173
noise analyzer, or equivalent. The voltage-noise density
at 1kHz is sample tested on production units. When
measuring op-amp voltage noise, only low-value, metal
film resistors are used in the test fixture.
The 0.1Hz to 10Hz peak-to-peak noise of the
MAX410/MAX412/MAX414 is measured using the test
en = Input voltage-noise density at the frequency of
interest
in = Input current-noise density at the frequency of
interest
T = Ambient temperature in Kelvin (K)
k = 1.28 x 10-23 J/K (Boltzman’s constant)
In Figure 1, Rp = R3 and Rn = R1 || R2. In a real application, the output resistance of the source driving the
input must be included with Rp and Rn. The following
example demonstrates how to calculate the total output-noise density at a frequency of 1kHz for the
MAX412 circuit in Figure 1.
Gain = 1000
R2
100kΩ
+5V
0.1µF
R1
100Ω
et
D.U.T
R3
100Ω
0.1µF
-5V
MAX410
MAX412
MAX414
Figure 1. Total Noise vs. Source Resistance Example
10-20
4kT at +25°C = 1.64 x
Rp = 100Ω
Rn = 100Ω || 100kΩ = 99.9 W
en = 1.5nV/√Hz at 1kHz
in = 1.2pA/√Hz at 1kHz
et = [(1.5 x 10-9)2 + (100 + 99.9)2 (1.2 x 10-12)2 + (1.64
x 10-20) (100 + 99.9)]1/2 = 2.36nV/√Hz at 1kHz
Output noise density = (100)et = 2.36µV/√Hz at 1kHz.
In general, the amplifier’s voltage noise dominates with
equivalent source resistances less than 200Ω. As the
equivalent source resistance increases, resistor noise
27Ω
3Ω
en
D.U.T
MAX410
MAX412
MAX414
Figure 2. Voltage-Noise Density Test Circuit
8
_______________________________________________________________________________________
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
100kΩ
+VS
2kΩ
10Ω
+VS
D.U.T
22µF
2kΩ
TO SCOPE x1
RIN = 1MΩ
MAX410
4.7µF
-VS
-VS
110kΩ
4.7µF
100kΩ
MAX410
MAX412
MAX414
0.1µF
24.9kΩ
Figure 3. 0.1Hz to 10Hz Voltage Noise Test Circuit
Current Noise Testing
100
The current-noise density can be calculated, once the
value of the input-referred noise is determined, by
using the standard expression given below:
GAIN (dB)
80
60
in =
[
] A/
eno 2 - (A VCL )2 (4kT)(Rn +Rp )
(Rn +Rp )(A VCL )
Hz
40
where:
Rn = Inverting input effective series resistance
Rp= Noninverting input effective series resistance
20
0
0.01
0.1
1
10
100
FREQUENCY (Hz)
Figure 4. 0.1Hz to 10Hz Voltage Noise Test Circuit, Frequency
Response
circuit shown in Figure 3. Figure 4 shows the frequency
response of the circuit. The test time for the 0.1Hz to
10Hz noise measurement should be limited to 10 seconds, which has the effect of adding a second zero to
the test circuit, providing increased attenuation for frequencies below 0.1Hz.
eno = Output voltage-noise density at the frequency of
interest (V/√Hz)
i n = Input current-noise density at the frequency of
interest (A/√Hz)
AVCL = Closed-loop gain
T = Ambient temperature in Kelvin (K)
k = 1.38 x 10-23 J/K (Boltzman’s constant)
Rp and Rn include the resistances of the input driving
source(s), if any.
If the Quan Tech model 5173 is used, then the AVCL
terms in the numerator and denominator of the equation
given above should be eliminated because the Quan
_______________________________________________________________________________________
9
MAX410/MAX412/MAX414
0.1µF
MAX410/MAX412/MAX414
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
909Ω
Rf
499Ω
+5V
0.022µF
Rn
10kΩ
100Ω
D.U.T
MAX410
MAX412
MAX414
eno
D.U.T
Rp
10kΩ
MAX410
MAX412
MAX414
0.022µF
-5V
Figure 6a. Voltage Follower Circuit with 3900pF Load
Figure 5. Current-Noise Test Circuit
Tech measures input-referred noise. For the circuit in
Figure 5, assuming Rp is approximately equal to Rn
and the measurement is taken with the Quan Tech
model 5173, the equation simplifies to:
in =
[
] A/
VS = ±5V
TA = +25°C
INPUT
1V/div
GND
OUTPUT
1V/div
GND
eno 2 - (1.64 × 10-20 )(20 × 103 )
(20 × 103 )
Hz
Input Protection
To protect amplifier inputs from excessive differential
input voltages, most modern op amps contain input
protection diodes and current-limiting resistors. These
resistors increase the amplifier’s input-referred noise.
They have not been included in the MAX410/MAX412/
MAX414, to optimize noise performance. The MAX410/
MAX412/MAX414 do contain back-to-back input protection diodes which will protect the amplifier for differential input voltages of ±0.1V. If the amplifier must be
protected from higher differential input voltages, add
external current-limiting resistors in series with the op
amp inputs to limit the potential input current to less
than 20mA.
Capacitive-Load Driving
Driving large capacitive loads increases the likelihood
of oscillation in amplifier circuits. This is especially true
for circuits with high loop gains, like voltage followers.
The output impedance of the amplifier and a capacitive
load form an RC network that adds a pole to the loop
response. If the pole frequency is low enough, as when
driving a large capacitive load, the circuit phase margin is degraded.
In voltage follower circuits, the MAX410/MAX412/
MAX414 remain stable while driving capacitive loads
as great as 3900pF (see Figures 6a and 6b).
10
VOUT
3900pF
VIN
1µs/div
Figure 6b. Driving 3900pF Load as Shown in Figure 6a
When driving capacitive loads greater than 3900pF,
add an output isolation resistor to the voltage follower
circuit, as shown in Figure 7a. This resistor isolates the
load capacitance from the amplifier output and restores
the phase margin. Figure 7b is a photograph of the
response of a MAX410/MAX412/MAX414 driving a
0.015µF load with a 10Ω isolation resistor
The capacitive-load driving performance of the
MAX410/MAX412/MAX414 is plotted for closed-loop
gains of -1V/V and -10V/V in the % Overshoot vs.
Capacitive Load graph in the Typical Operating
Characteristics.
Feedback around the isolation resistor RI increases the
accuracy at the capacitively loaded output (see Figure 8).
The MAX410/MAX412/MAX414 are stable with a 0.01µF
load for the values of RI and CF shown. In general, for
decreased closed-loop gain, increase RI or CF. To drive
larger capacitive loads, increase the value of CF.
______________________________________________________________________________________
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
MAX410
MAX412
MAX414
CF
82pF
VIN
1kΩ
RI
10Ω
RI
10Ω
D.U.T
D.U.T
VOUT
CL
0.01µF
VOUT
VIN
CL > 0.015µF
MAX410
MAX412
MAX414
909Ω
Figure 8. Capacitive-Load Driving Circuit with Loop-Enclosed
Isolation Resistor
Figure 7a. Capacitive-Load Driving Circuit
VS = ±5V
TA = +25°C
INPUT
1V/div
10kΩ
GND
1
OUTPUT
1V/div
GND
NULL 8
NULL
MAX410
V+
7
1µs/div
Figure 7b. Driving a 0.015µF Load with a 10Ω Isolation Resistor
TDFN Exposed Paddle Connection
On TDFN packages, there is an exposed paddle that
does not carry any current but should be connected to
V- (not the GND plane) for rated power dissipation.
Total Supply Voltage Considerations
Although the MAX410/MAX412/MAX414 are specified
with ±5V power supplies, they are also capable of single-supply operation with voltages as low as 4.8V. The
minimum input voltage range for normal amplifier operation is between V- + 1.5V and V+ - 1.5V. The minimum
room-temperature output voltage range (with 2kΩ load)
Figure 9. MAX410 Offset Null Circuit
is between V+ - 1.4V and V- + 1.3V for total supply voltages between 4.8V and 10V. The output voltage range,
referenced to the supply voltages, decreases slightly
over temperature, as indicated in the ±5V Electrical
Characteristics tables. Operating characteristics at total
supply, voltages of less than 10V are guaranteed by
design and PSRR tests.
MAX410 Offset Voltage Null
The offset null circuit of Figure 9 provides approximately
±450µV of offset adjustment range, sufficient for zeroing
offset over the full operating temperature range.
______________________________________________________________________________________
11
MAX410/MAX412/MAX414
10kΩ
499Ω
MAX410/MAX412/MAX414
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
Ordering Information (continued)
PART
TEMP RANGE
PIN-PACKAGE
MAX412CPA
0°C to +70°C
8 Plastic DIP
MAX412BCPA
0°C to +70°C
8 Plastic DIP
MAX412CSA
0°C to +70°C
8 SO
MAX412BCSA
0°C to +70°C
8 SO
MAX412EPA
-40°C to +85°C
-40°C to +85°C
8 Plastic DIP
MAX412ESA
-40°C to +85°C
8 SO
14 OUT4
OUT1 1
IN1-
13 IN4-
2
4
1
IN1+
V+ 4
-40°C to +85°C
8 SO
MAX414CPD
0°C to +70°C
14 Plastic DIP
MAX414BCPD
0°C to +70°C
14 Plastic DIP
MAX414CSD
0°C to +70°C
14 SO
-40°C to +85°C
14 Plastic DIP
MAX414BEPD
-40°C to +85°C
14 Plastic DIP
MAX414ESD
-40°C to +85°C
14 SO
MAX414BESD
-40°C to +85°C
14 SO
11 V-
MAX414
2
3
10 IN3+
IN2- 6
9
IN3-
OUT2 7
8
OUT3
DIP/SO
14 SO
MAX414EPD
12 IN4+
3
IN2+ 5
MAX412BESA
0°C to +70°C
TOP VIEW
8 Plastic DIP
MAX412BEPA
MAX414BCSD
Pin Configurations (continued)
Chip Information
MAX410 TRANSISTOR COUNT: 132
MAX412 TRANSISTOR COUNT: 262
MAX414 TRANSISTOR COUNT: 2 262 (hybrid)
PROCESS: Bipolar
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.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.
PACKAGE TYPE
12
PACKAGE CODE
DOCUMENT NO.
8 Plastic DIP
P8-1
21-0043
8 SO (MAX410)
S8-2
21-0041
8 SO (MAX412)
S8-4
21-0041
8 TDFN-EP
T833-2
21-0137
14 Plastic DIP
P14-3
21-0043
14 SO
S14-1
21-0041
______________________________________________________________________________________
Single/Dual/Quad, 28MHz, Low-Noise,
Low-Voltage, Precision Op Amps
REVISION
NUMBER
REVISION
DATE
5
10/08
Added rugged plastic product.
9/09
Added military temperature operating range and new Electrical
Characteristics table for the MAX410. Updated Package Information table.
6
DESCRIPTION
PAGES
CHANGED
1, 11
1, 2, 4, 12–13
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 13
© 2009 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
MAX410/MAX412/MAX414
Revision History
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