ICL7650MTV1/HR
更新时间:2024-09-18 19:04:17
品牌:MAXIM
描述:Operational Amplifier, 1 Func, 10uV Offset-Max, CMOS, MBCY8, TO-99, 8 PIN
ICL7650MTV1/HR 概述
Operational Amplifier, 1 Func, 10uV Offset-Max, CMOS, MBCY8, TO-99, 8 PIN 运算放大器
ICL7650MTV1/HR 规格参数
是否Rohs认证: | 不符合 | 生命周期: | Obsolete |
零件包装代码: | TO-99 | 包装说明: | TO-99, 8 PIN |
针数: | 8 | Reach Compliance Code: | not_compliant |
ECCN代码: | EAR99 | HTS代码: | 8542.33.00.01 |
风险等级: | 5.68 | Is Samacsys: | N |
放大器类型: | OPERATIONAL AMPLIFIER | 架构: | CHOPPER-STAB |
最大平均偏置电流 (IIB): | 0.0001 µA | 25C 时的最大偏置电流 (IIB): | 0.00001 µA |
标称共模抑制比: | 130 dB | 频率补偿: | YES |
最大输入失调电压: | 10 µV | JESD-30 代码: | O-MBCY-W8 |
JESD-609代码: | e0 | 低-偏置: | YES |
低-失调: | YES | 微功率: | NO |
负供电电压上限: | -9 V | 标称负供电电压 (Vsup): | -5 V |
功能数量: | 1 | 端子数量: | 8 |
最高工作温度: | 70 °C | 最低工作温度: | |
封装主体材料: | METAL | 封装等效代码: | CAN8,.2 |
封装形状: | ROUND | 封装形式: | CYLINDRICAL |
峰值回流温度(摄氏度): | NOT SPECIFIED | 功率: | NO |
电源: | +-5 V | 可编程功率: | NO |
认证状态: | Not Qualified | 筛选级别: | MIL-STD-883 Class B (Modified) |
标称压摆率: | 2.5 V/us | 子类别: | Operational Amplifiers |
最大压摆率: | 2 mA | 供电电压上限: | 9 V |
标称供电电压 (Vsup): | 5 V | 表面贴装: | NO |
技术: | CMOS | 温度等级: | COMMERCIAL |
端子面层: | Tin/Lead (Sn/Pb) | 端子形式: | WIRE |
端子位置: | BOTTOM | 处于峰值回流温度下的最长时间: | NOT SPECIFIED |
标称均一增益带宽: | 2000 kHz | 宽带: | NO |
Base Number Matches: | 1 |
ICL7650MTV1/HR 数据手册
通过下载ICL7650MTV1/HR数据手册来全面了解它。这个PDF文档包含了所有必要的细节,如产品概述、功能特性、引脚定义、引脚排列图等信息。
PDF下载19-0960; Rev 2; 1/00
Chopper-Stabilized Op Amps
General Description
Features
Maxim’s ICL7650/ICL7653 are chopper-stabilized
amplifiers, ideal for low-level signal processing applica-
tions. Featuring high performance and versatility, these
devices combine low input offset voltage, low input bias
current, wide bandwidth, and exceptionally low drift
over time and temperature. Low offset is achieved
through a nulling scheme that provides continuous
error correction. A nulling amplifier alternately nulls
itself and the main amplifier. The result is an input offset
voltage that is held to a minimum over the entire operat-
ing temperature range.
ꢀ ICL7650/53 are Improved Second Sources to
ICL7650B/53B
ꢀ Lower Supply Current: 2mA
ꢀ Low Offset Voltage: 1µV
ꢀ No Offset Voltage Trimming Needed
ꢀ High-Gain CMRR and PSRR: 120dB min
ꢀ Lower Offset Drift with Time and Temperature
ꢀ Extended Common-Mode Voltage Range
ꢀ Low DC Input Bias Current: 10pA
ꢀ Monolithic, Low-Power CMOS Design
The ICL7650B/ICL7653B are exact replacements for
Intersil’s ICL7650B/ICL7653B. These devices have a
10µV max offset voltage, a 0.1µV/°C max input offset
voltage temperature coefficient, and a 20pA max bias
current—all specified over the commercial temperature
range.
Ordering Information
A 14-pin version is available that can be used with
either an internal or external clock. The 14-pin version
has an output voltage clamp circuit to minimize over-
load recovery time.
PART
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
-20°C to +85°C
-20°C to +85°C
-55°C to +125°C
-55°C to +125°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
-20°C to +85°C
-55°C to +125°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
8 SO
ICL7650CSA
ICL7650CSD
ICL7650CPA
ICL7650CPD
ICL7650CTV
ICL7650C/D
ICL7650IJA
14 SO
8 Plastic DIP
14 Plastic DIP
8 TO-99
Applications
Condition Amplifier
Precision Amplifier
Instrumentation Amplifier
Thermocouples
Dice
8 CERDIP
14 CERDIP
8 CERDIP
14 CERDIP
8 SO
ICL7650IJD
ICL7650MTV
ICL7650MJD
ICL7650BCSA
ICL7650BCSD
ICL7650BCPA
ICL7650BCPD
ICL7650BCTV
ICL7650BC/D
ICL7653CSA
ICL7653CPA
ICL7653CTV
ICL7653IJA
Thermistors
Strain Gauges
14 SO
8 Plastic DIP
14 Plastic DIP
8 TO-99
Typical Operating Circuit
Dice
8 SO
8 Plastic DIP
8 TO-99
CLAMP
INPUT
8 CERDIP
8 CERDIP
8 SO
OUTPUT
ICL7653MTV
ICL7653BCSA
ICL7653BCPA
ICL7653BCTV
ICL7650
ICL7653
C
8 Plastic DIP
8 TO-99
R
C
INVERTING AMPLIFIER
WITH OPTIONAL CLAMP
Pin Configurations appear at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
Chopper-Stabilized Op Amps
ABSOLUTE MAXIMUM RATINGS
Total Supply Voltage (V+ to V-)..............................................18V
Input Voltage ........................................(V+ + 0.3V) to (V- - 0.3V)
Voltage on Oscillator Control Pins
(except EXT/CLOCK IN).............................................V+ to V-
Voltage on EXT/CLOCK IN..................(V+ + 0.3V) to (V+ - 6.0V)
Duration of Output Short Circuit ....................................Indefinite
Current into Any Pin ............................................................10mA
Current into Any Pin while Operating (Note 1)...................100µA
8-Pin TO-99 (derate 6.7mW/°C above +70°C)............533mW
14-Pin SO (derate 8.3mW/°C above +70°C)...............667mW
14-Pin PDIP (derate 10.0mW/°C above +70°C)..........800mW
14-Pin CERDIP (derate 9.1mW/°C above +70°C).......727mW
Operating Temperature Ranges
ICL765_C__/ICL755_BC__ ...............................0°C to +70°C
ICL765_I__/ICL755_BI__................................-20°C to +85°C
ICL765_M__/ICL755_BM__..........................-55°C to +125°C
Storage Temperature Range.............................-65°C to +150°C
Junction Temperature......................................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
Continuous Total Power Dissipation (T = +70°C)
A
8-Pin SO (derate 5.88mW/°C above +70°C)...............471mW
8-Pin PDIP (derate 6.9mW/°C above +70°C)...............552mW
8-Pin CERDIP (derate 8.0mW/°C above +70°C).........640mW
Note 1: Maxim recommends limiting the input current to 100µA to avoid latchup problems. A value of 1mA is typically safe; however,
this is not guaranteed.
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—ICL7650B/ICL7653B
(Circuit of Figure 1, V+ = +5V, V- = -5V, T = +25°C, unless otherwise noted.)
A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
0.7
10
MAX
UNITS
T
A
= +25°C
5
Input Offset Voltage
V
OS
-55°C < T < +85°C
µV
A
-55°C < T < +125°C
5.0
A
T
= +25°C
50
0.01
1.5
35
A
∆V
Average Temperature Coefficient
of Input Offset Voltage
OS
∆T
µV/°C
pA
-20°C < T < +85°C
A
0.05
10
T
= +25°C
A
Input Bias Current
I
Doubles every 10°
0°C < T < +70°C
A
BIAS
-20°C < T < +85°C
100
0.5
A
Input Offset Current (Note 2)
Input Resistance
I
T
A
= +25°C
pA
Ω
OS
12
R
IN
10
5
8
Large-Signal Voltage Gain
A
VOL
R = 10kΩ
L
V/V
1 · 10
5 · 10
R = 10kΩ
4.7
4.85
L
Output Voltage Swing (Note 3)
V
OUT
V
R = 100kΩ
L
4.95
Common-Mode Voltage Range
Common-Mode Rejection Ratio
Power-Supply Rejection Ratio
Input Noise Voltage
Input Noise Current
Unity-Gain Bandwidth
Slew Rate
CMVR
CMRR
PSRR
-5.0 -5.2 to +2.0 1.6
V
dB
CMVR = -5V to +1.6V
V+ to V- = 3V to 8V
120
120
130
130
2
dB
e
np-p
R = 100Ω, f = 0 to 10Hz
S
µVp-p
pA/√Hz
MHz
V/µs
µs
I
n
f = 10Hz
0.01
2.0
2.5
0.2
20
GBW
SR
C = 50pF, R = 10kΩ
L
L
Rise Time
t
r
Overshoot
%
Operating Supply Range
Supply Current
V+ to V-
4.5
16
V
I
No load
2.0
3.5
mA
SUPP
2
_______________________________________________________________________________________
Chopper-Stabilized Op Amps
ELECTRICAL CHARACTERISTICS—ICL7650B/ICL7653B (continued)
(Circuit of Figure 1, V+ = +5V, V- = -5V, T = +25°C, unless otherwise noted.)
A
PARAMETER
SYMBOL
CONDITIONS
Pins 12–14 open (DIP)
R = 100kΩ
MIN
120
25
TYP
200
70
MAX
375
UNITS
Hz
Internal Chopping Frequency
Clamp On Current (Note 4)
Clamp Off Current (Note 4)
f
ch
200
µA
L
-4.0V < V
< +4.0V
1
pA
OUT
nV/
√month
Offset Voltage vs. Time
No load
100
Note 2: I = 2 · I
BIAS
OS
Note 3: OUTPUT and CLAMP pins not connected.
Note 4: See Output Clamp section for details.
ELECTRICAL CHARACTERISTICS—ICL7650/ICL7653
(Circuit of Figure 1, V+ = +5V, V- = -5V, T = +25°C, unless otherwise noted.) (Note 5)
A
PARAMETER
SYMBOL
CONDITIONS
ICL765_
ICL765_B
0°C ≤ T ≤ +70°C
MIN
TYP
0.7
1.0
1.0
1.0
10
MAX
5.0
10
UNITS
T
= +25°C
A
Input Offset Voltage
V
OS
10
µV
A
ICL765_
(Note 6)
-20°C ≤ T ≤ +85°C
10
A
-55°C ≤ T ≤ +125°C
50
A
ICL765_B, 0°C ≤ T ≤ +70°C
0.01
0.01
0.01
0.01
0.25
4
0.05
0.1
0.05
0.05
1.5
10
A
0°C ≤ T ≤ +70°C
A
∆V
∆T
Average Temperature Coefficient
of Input Offset Voltage (Note 6)
OS
-20°C ≤ T ≤ +85°C
µV/°C
A
ICL765_
-55°C ≤ T ≤ +85°C
A
+85°C ≤ T ≤ +125°C
A
ICL765_
T
A
= +25°C
ICL765_B
12
20
Input Bias Current
I
B
0°C ≤ T ≤ +70°C
20
100
200
10
pA
A
ICL765_
-20°C ≤ T ≤ +85°C
50
A
-55°C ≤ T ≤ +125°C
0.3
A
12
Input Resistance
R
IN
Ω
10
8
8
R = 10kΩ, T = +25°C
1 · 10
5 · 10
L
A
8
8
8
0°C ≤ T ≤ +70°C
0.5 · 10
0.5 · 10
0.2 · 10
4.7
A
Large-Signal Voltage Gain
A
V/V
VOL
-20°C ≤ T ≤ +85°C
A
-55°C ≤ T ≤ +125°C
A
R = 10kΩ
L
4.85
4.95
Output Voltage Swing (Note 3)
Common-Mode Voltage Range
V
OUT
V
V
R = 100kΩ
L
0°C ≤ T ≤ +70°C
-5.0 -5.2 to +3.0 2.5
-5.0 -5.2 to +3.0 2.5
-4.5 -4.0 to +3.0 2.5
A
CMVR
-20°C ≤ T ≤ +85°C
A
-55°C ≤ T ≤ +125°C
A
_______________________________________________________________________________________
3
Chopper-Stabilized Op Amps
ELECTRICAL CHARACTERISTICS—ICL7650/ICL7653 (continued)
(Circuit of Figure 1, V+ = +5V, V- = -5V, T = +25°C, unless otherwise noted.) (Note 5)
A
PARAMETER
Common-Mode Rejection Ratio
Power-Supply Rejection Ratio
Input Noise Voltage
Input Noise Current
Unity-Gain Bandwidth
Slew Rate
SYMBOL
CMRR
CONDITIONS
CMVR = -5V to +2.5V
V+ to V- = 3V to 8V
MIN
120
120
TYP
130
130
2
MAX
UNITS
dB
PSRR
dB
e
np-p
R = 100Ω, f = 0 to 10Hz
S
µVp-p
pA/√Hz
MHz
V/µs
µs
I
n
f = 10Hz
0.01
2.0
2.5
0.2
20
GBW
SR
C = 50pF, R = 10kΩ
L
L
Rise Time
t
r
Overshoot
%
Operating Supply Range
Supply Current
V+ to V-
4.5
16
2.0
V
I
No load
1.2
200
70
1
mA
SUPP
Internal Chopping Frequency
Clamp On Current (Note 4)
Clamp Off Current (Note 4)
f
Pins 13 and 14 open (DIP)
R = 100kΩ
120
25
375
200
Hz
CLKOUT
µA
L
-4.0 ≤ V
≤ +4.0V
pA
OUT
nV/
√month
Offset Voltage vs. Time
100
Note 3: OUTPUT and CLAMP pins not connected.
Note 4: See Output Clamp section for details.
Note 5: All pins are designed to withstand electrostatic discharge (ESD) levels in excess of 2000V (MIL STD 8838 Method 3015.1
test circuit).
Note 6: Sample tested. Limits are not used to calculate outgoing quality level.
Typical Operating Characteristics
(Circuit of Figure 1, V+ = +5V, V- = -5V, T = +25°C, unless otherwise noted.)
A
MAXIMUM OUTPUT CURRENT
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
CLOCK RIPPLE REFERRED TO INPUT
vs. SUPPLY VOLTAGE
vs. TEMPERATURE
4
3
1k
100
10
3
2
1
0
0.1µF
1µF
SOURCE CURRENT
2
1
BROADBAND
NOISE
0
(A = 1000)
V
-10
-20
-30
1
SINK CURRENT
0.1
2
4
6
8
10
12
14
16
25
50
75
100
125
150
4
6
8
10
12
14
16
TOTAL SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
TOTAL SUPPLY VOLTAGE (V)
4
_______________________________________________________________________________________
Chopper-Stabilized Op Amps
Typical Operating Characteristics (continued)
(Circuit of Figure 1, V+ = +5V, V- = -5V, T = +25°C, unless otherwise noted.)
A
SUPPLY CURRENT vs.
AMBIENT TEMPERATURE
COMMON-MODE INPUT VOLTAGE RANGE
vs. SUPPLY VOLTAGE
INPUT OFFSET VOLTAGE
vs. CHOPPING FREQUENCY
8
7
6
5
4
3
2
1
0
3
2
1
0
-10
-8
-6
-4
-2
0
NEGATIVE LIMIT
POSITIVE LIMIT
-50 -25
0
25
50
75 100 125
0
1
2
3
4
5
6
7
8
10
100
1k
10k
AMBIENT TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
CHOPPING FREQUENCY (CLOCK OUT) (Hz)
INPUT OFFSET VOLTAGE CHANGE
vs. SUPPLY VOLTAGE
10Hzp-p NOISE VOLTAGE
vs. CHOPPING FREQUENCY
OPEN-LOOP GAIN AND PHASE SHIFT
vs. FREQUENCY
ICL7650toac09
-3
-2
-1
0
5
4
3
2
1
0
160
140
120
100
80
50
70
90
110
130
1
60
2
R = 10kΩ
EXT
40
L
C
= 0.1µF
3
20
4
6
8
10
12
14
16
10
100
1k
10k
0.01 0.1
1
10 100 1k
FREQUENCY (Hz)
10k 100k
TOTAL SUPPLY VOLTAGE (V)
CHOPPING FREQUENCY (CLOCK-OUT) (Hz)
OPEN-LOOP GAIN AND PHASE SHIFT
vs. FREQUENCY
VOLTAGE FOLLOWER LARGE-SIGNAL
PULSE RESPONSE
VOLTAGE FOLLOWER LARGE-SIGNAL
PULSE RESPONSE
ICL7650toac10
160
140
120
100
80
3
3
2
2
1
50
CLOCK OUT LOW
1
70
CLOCK OUT LOW
90
0
0
110
130
CLOCK OUT HIGH
-1
-2
-3
-1
-2
-3
60
CLOCK OUT HIGH
R = 10kΩ
EXT
40
L
C
= 1.0µF
20
0.01 0.1
1
10 100 1k
FREQUENCY (Hz)
10k 100k
-1.0 -0.5
0
0.5 1.0 1.5 2.0 2.5 3.0
-1.0 -0.5
0
0.5 1.0 1.5 2.0 2.5 3.0
TIME (µs)
TIME (µs)
_______________________________________________________________________________________
5
Chopper-Stabilized Op Amps
R2
1M
ICL7650
A
A
B
C
INT/EXT
EXT CLK IN
CLK OUT
OSC
R1
1M
OUTPUT
ICL7650
ICL7653
INTERNAL
BIAS
P
C
+
+IN
C
R
OUTPUT
CLAMP
MAIN
C
-
-IN
A
+
C
N
0.1µF 0.1µF
NULL
A
-
B
Figure 1. ICL7650 Test Circuit
CAP RETURN
C
EXTA
C
EXTB
Detailed Description
Figure 2 shows the major elements of the ICL7650/
ICL7653. Two amplifiers are illustrated, the main amplifi-
er and the nulling amplifier, both of which have offset-
null capability. The main amplifier is connected full time
from the input to the output. The nulling amplifier, under
control of the chopper-frequency oscillator and clock
circuit, alternately nulls itself and the main amplifier. This
nulling arrangement, which is independent of the output
level, operates over the full power-supply and common-
mode ranges. The ICL7650/ICL7653 exhibit an excep-
EXT CLK IN
A = CLK OUT
A
B
C
Figure 2. Block Diagram
tionally high CMRR, PSRR, and A
. Their nulling
VOL
connections, which are MOSFET back gates, have inher-
ently high impedance. Two external capacitors provide
storage for the nulling potentials and the necessary
nulling-loop time constants.
Intermodulation
Intermodulation effects can cause problems in older
chopper-stabilized amplifier modules. Intermodulation
occurs since the amplifier has a finite AC gain, and
therefore will have a small AC signal at the input. In a
chopper-stabilized module, this small AC signal is
detected, chopped, and fed into the offset-correction
circuit. This results in spurious outputs at the sum and
difference frequencies of the chopping and input signal
frequencies. Other intermodulation effects in chopper-
stabilized modules include gain and phase anomalies
near the chopping frequency.
The ICL7650/ICL7653 minimize chopper-frequency
charge injection at the input terminals by carefully bal-
ancing the input switches. Feed-forward injection into
the compensation capacitor, the main cause of output
spikes in this type of circuit, is also minimized.
Output Clamp (ICL7650 Only)
The output clamp reduces the overload recovery time
inherent with chopper-stabilized amplifiers. When tied to
the summing junction or inverting input pin, a current path
between this point and the output occurs just before the
output device saturates. This prevents uncontrolled input
differential and the consequent charge build-up on the
correction-storage capacitors, while causing only a slight
reduction in the output swing.
These effects are substantially reduced in the
ICL7650/ICL7653, which add to the nulling circuit a
dynamic current that compensates for the AC signal on
the inputs. Unlike modules, the ICL7650/ICL7653 can
precisely compensate for the finite AC gain, since both
the AC gain rolloff and the intermodulation compensation
current are controlled by internal matched capacitors.
6
_______________________________________________________________________________________
Chopper-Stabilized Op Amps
leakage at the null capacitor pins) becomes excessive
and 1µF external capacitors are required.
Nulling Capacitor Connection
Separate pins are provided for CRETN and CLAMP in
the ICL7650. If you do not need the clamp feature,
order the ICL7653; this device only offers the CRETN pin
and will produce slightly lower noise and improved AC
common-mode rejection. If you need to use the clamp
feature, order the ICL7650 and connect the external
capacitors to V-. To prevent load-current IR drops and
other extraneous signals from being injected into the
capacitors, use a separate PC board trace to connect
the capacitor commons directly to the V- pin. The out-
side foil of the capacitors should be connected to the
low-impedance side of the null storage circuit, V- or
Output Stage/Load Driving
The ICL7650/ICL7653 somewhat resemble a transcon-
ductance amplifier whose open-loop gain is proportional
to load resistance. This behavior is apparent when loads
are less than the high-impedance stage (approximately
18kΩ for one output circuit). The open-loop gain, for
example, will be 17dB lower with a 1kΩ load than with a
10kΩ load. This lower gain is of little consequence if the
amplifier is used strictly for DC since the DC gain is typi-
cally greater than 120dB, even with a 1kΩ load. For
wideband applications, however, the best frequency
response will be achieved with a load resistor of 10kΩ or
higher. The result will be a smooth 6dB per octave
response from 0.1Hz to 2MHz, with phase shifts of less
than 10° in the transition region where the main amplifier
takes over from the null amplifier.
C
. This will act as an ESD voltage shield.
RETN
Clock Operation
The ICL7650’s internal oscillator generates a 200Hz fre-
quency, which is available at the CLK OUT pin. The
device can also be operated with an external clock, if
desired. An internal pull-up permits the INT/EXT pin to
be left open for normal operation. However, the internal
clock must be disabled and INT/EXT must be tied to V-
if an external clock is used. An external clock signal
may then be applied to the EXT CLK IN pin. The duty
cycle of the external clock is not critical at low frequen-
cies. However, a 50% to 80% positive duty cycle is pre-
ferred for frequencies above 500Hz, since the
capacitors are charged only when EXT CLK IN is high.
This ensures that any transients have time to settle
before the capacitors are turned off. The external clock
should swing between ground and V+ for power sup-
plies up to 6V, and between V+ and (V+ - 6V) for
higher supply voltages.
Component Selection
, the two required capacitors, have
EXTB
C
and C
EXTA
optimum values depending on the clock or chopping
frequency. The correct value is 0.1µF for the preset
internal clock. When using an external clock, scale this
component value in proportion to the relationship
between the chopping frequency and the nulling time
constant. A low-leakage ceramic capacitor may prove
suitable for many applications; however, a high-quality
film-type capacitor (such as mylar) is preferred. For
lowest settling time at initial turn-on, use capacitors with
low dielectric absorption (such as polypropylene
types). With low-dielectric-absorption capacitors, the
ICL7650/ICL7653 will settle to 1µV offset in 100ms, but
several seconds may be required if ceramic capacitors
are used.
To avoid a capacitor imbalance during overload, use a
strobe signal. Neither capacitor will be charged if a
strobe signal is connected to EXT CLK IN so that it is
low while the overload signal is being applied to the
amplifier. A typical amplifier will drift less than 10µVs
since the leakage of the capacitor pins is quite low at
room temperature. Relatively long measurements may
be made with little change in offset.
Thermoelectric Effects
Thermoelectric effects developed in thermocouple
junctions of dissimilar materials (metals, alloys, silicon,
etc.) ultimately limit precision DC measurements.
Unless all junctions are at the same temperature, ther-
moelectric voltages (typically around 10µV/°C, but up
to hundreds of µV/°C for some materials) will be gener-
ated. In order to realize the extremely low offset volt-
ages that the chopper amplifier can provide, take
special precautions to avoid temperature gradients. To
eliminate air movement, enclose all components (par-
ticularly those caused by power-dissipating elements in
the system). Minimize power-supply voltages and
power dissipation, and use low-thermoelectric-coeffi-
cient connections where possible. It is advisable to
separate the device surrounding heat-dissipating ele-
ments, and to use high-impedance loads.
Applications Information
Device Selection
In applications that require lowest noise, Maxim’s
ICL7652 may be preferred over the ICL7650/ICL7653.
The ICL7650/ICL7653 offer a higher gain-bandwidth
product and lower input bias currents, while the
ICL7652 reduces noise by using larger input FETs.
These larger FETs, however, increase the leakage at
the ICL7652’s external null pins. Therefore, the
ICL7650/ICL7653 can operate to a higher temperature
with 0.1µF capacitors before the clock ripple (due to
_______________________________________________________________________________________
7
Chopper-Stabilized Op Amps
ing to decrease the voltage difference between inputs
Input Guarding
Low-leakage, high-impedance CMOS inputs allow the
ICL7650/ICL7653 to measure high-impedance sources.
Stray leakage paths can decrease input resistance and
increase input currents unless inputs are guarded.
Boards must be thoroughly cleaned with TCE or alcohol
and blown dry with compressed air. The board should
be coated with epoxy or silicone after cleaning to pre-
vent contamination.
and adjacent metal runs. Use a 10-lead pin circle, with
the leads of the device formed so that the holes adja-
cent to the inputs are empty when it is inserted in the
board to accomplish input guarding of the 8-pin TO-99
package. A conductive ring surrounding the inputs, the
“guard,” is connected to a low-impedance point that is
approximately the same voltage as the inputs. The
guard then absorbs the leakage current from the high-
voltage pins. Typical guard connections are shown in
Figure 3.
Leakage currents may cause trouble even with properly
cleaned and coated boards, particularly since the input
pins are adjacent to pins that are at supply potentials.
Leakage can be significantly reduced by using guard-
R2
R1
INPUT
R3*
OUTPUT
OUTPUT
INPUT
R3*
INVERTING AMPLIFIER
FOLLOWER
*
USE R3 TO COMPENSATE FOR LARGE
SOURCE RESISTANCES, OR FOR CLAMP
OPERATION (FIGURE 5).
R2
EXTERNAL
CAPACITORS
V+
V-
R3*
OUTPUT
OUTPUT
7 8
4
1
6
5
2
EXTERNAL
CAPACITORS
3
R1
GUARD
INPUT
NONINVERTING AMPLIFIER
BOTTOM VIEW
R1 R2
SHOULD BE LOW IMPEDANCE FOR
R1 + R2 OPTIMUM GUARDING.
BOARD LAYOUT FOR INPUT GUARDING
WITH TO-99 PACKAGE.
NOTE:
Figure 3. Input Guard Connection
_______________________________________________________________________________________
8
Chopper-Stabilized Op Amps
The 14-pin DIP configuration has been specifically
designed to ease input guarding. The pins adjacent to
the inputs are not used.
the amplifier’s inverting input, integrate the error, and
drive the amplifier’s noninverting input to correct for the
offset voltage detected at the inverting input. The cir-
cuit’s DC offset characteristics are determined by the
ICL7650/ICL7653, and its AC performance is deter-
mined by the high-speed amplifier. While this circuit
continuously and automatically adjusts the amplifier’s
offset to less than 5µV, it does not correct for errors
caused by the input bias current, so the value of resis-
Pin Compatibility
The ICL7653’s pinout generally corresponds to that of
industry-standard 8-pin devices such as the LM741 or
LM101. However, its external null storage capacitors
are connected to pins 1 and 8; whereas most op amps
leave these pins open or use them for offset null or
compensation capacitors.
tor R should be as low as is practical. This technique
F
can be used with any op amp that is configured as an
inverting amplifier.
The OP05 and OP07 op amps can be converted for
ICL7650/ICL7653 operation. This can be accomplished
by removing the offset null potentiometer, which is con-
nected from pins 1 and 8 to V+, and replacing it with
two capacitors connected from pins 1 and 8 to V-. For
LM108 devices, the compensation capacitor is
replaced by the external nulling capacitors. Pin 5 is the
output clamp connection on the ICL7650/ICL7653. By
removing any circuit connections from this pin, the
LM101/LM748/LM709 devices can undergo a similar
conversion.
Figures 5 and 6 illustrate basic inverting and noninvert-
ing amplifier circuits. Both figures show an output
clamping circuit being used to enhance overload
recovery performance. Supply voltage ( 8V max) and
output drive capability (10kΩ load for full swing) are the
only limitations to consider when replacing other op
amps with the ICL7650/ICL7653. Use a simple booster
circuit to overcome these limitations (Figure 7). This
enables the full output capabilities of the LM118 (or any
other standard device) to be combined with the input
capabilities of the ICL7650/ICL7653. Observe the loop
gain stability carefully when the feedback network is
added, particularly when a slower amplifier such as the
LM741 is used.
Typical Applications
Figure 4 shows the ICL7650/ICL7653 automatically
nulling the offset voltage of a high-speed amplifier. The
ICL7650/ICL7653 continuously monitor the voltage at
A lower voltage supply is required when mixing the
ICL7650/ICL7653 with circuits that operate at 15V sup-
plies. One approach is to use a highly efficient voltage
divider. This is illustrated in Figure 8, where the ICL7660
voltage converter is used to convert +15V to +7.5V.
R
F
R
IN
R2
V
HIGH-
SPEED
AMP
OUT
CLAMP
R1
1k
INPUT
OUTPUT
ICL7650
47Ω
10k
C
(R1 || R2) ≥ 100kΩ
FOR FULL CLAMP EFFECT
R
0.1µF
100k
C
NOTE: R1 || R2 INDICATES THE
PARALLEL COMBINATION OF
R1 || R2.
0.1µF 0.1µF
ICL7650
ICL7653
Figure 5. Inverting Amplifier with Optional Clamp
Figure 4. Nulling a High-Speed Amplifier
_______________________________________________________________________________________
9
Chopper-Stabilized Op Amps
0.1µF 0.1µF
+7.5V
CLAMP
+15V
-15V
C
+
INPUT
OUT
R
741
IN
ICL7650
C
OUTPUT
-
ICL7650
R2
R1
CLAMP
R3
-7.5V
10k
0.1µF 0.1µF
10k
R3 + (R1 || R2) > 100kΩ
FOR FULL CLAMP EFFECT
NOTE: R1 || R2 INDICATES THE
PARALLEL COMBINATION OF
R1 || R2.
Figure 7. Using an Industry-Standard 741 to Boost Output
Drive Capability
Figure 6. Noninverting Amplifier with Optional Clamp
Chip Topography
INT/EXT
EXT/CLK IN
8
3
2
4
+15V
C
EXTB
INT/
CLK OUT
ICL7660
10µF
+7.5V
0V
C
EXTA
10µF
5
V+
6
OUTPUT
1M
0.090"
(2.29mm)
Figure 8. Splitting +15V with an ICL7660, 95% Efficiency
(Same for -15V)
-INPUT
+INPUT
V-
CLAMP
C
RETN
0.069"
(1.75mm)
10 ______________________________________________________________________________________
Chopper-Stabilized Op Amps
Pin Configurations
TOP VIEW
C
EXTB
7
C
1
2
3
4
5
6
7
14 INT/EXT
13 EXT/CLK IN
12 INT/CLK OUT
11 V+
EXTB
EXTA
8
C
V+
6
EXTA
C
C
1
2
3
4
8
7
6
5
C
EXTB
1
3
EXTA
N.C. (GUARD)
-INPUT
-INPUT
+INPUT
V-
V+
ICL7650
MAX7650
-INPUT
2
OUTPUT
ICL7650
OUTPUT
CLAMP
+INPUT
10 OUTPUT
N.C. (GUARD)
V-
9
8
CLAMP
5
+INPUT
CLAMP
4
V-
TO-99
C
RETN
SO/DIP/CERDIP
SO/DIP/CERDIP
N.C. = NO INTERNAL CONNECTION
C
EXTB
8
C
V+
EXTA
1
3
7
C
1
2
3
4
8
C
EXTB
EXTA
-INPUT
+INPUT
V-
7
6
5
V+
OUTPUT
-INPUT
2
6
OUTPUT
ICL7653
ICL7653
5
C
RETN
+INPUT
C
RETN
4
V-
SO/DIP/CERDIP
TO-99
______________________________________________________________________________________ 11
Chopper-Stabilized Op Amps
Package Information
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.
12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2000 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
ICL7650MTV1/HR 相关器件
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ICL7650S | INTERSIL | 2MHz, Super Chopper-Stabilized Operational Amplifier | 获取价格 | |
ICL7650S | RENESAS | 2MHz, Super Chopper-Stabilized Operational Amplifier | 获取价格 | |
ICL7650SCBA-1 | INTERSIL | 2MHz, Super Chopper-Stabilized Operational Amplifier | 获取价格 | |
ICL7650SCBA-1 | ROCHESTER | Operational Amplifier, 1 Func, 8uV Offset-Max, CMOS, PDSO8, PLASTIC, MS-012AA, SOIC-8 | 获取价格 | |
ICL7650SCBA-1T | INTERSIL | 2MHz, Super Chopper-Stabilized Operational Amplifier | 获取价格 | |
ICL7650SCBA-1Z | INTERSIL | 2MHz, Super Chopper-Stabilized Operational Amplifier | 获取价格 | |
ICL7650SCBA-1ZT | INTERSIL | 2MHz, Super Chopper-Stabilized Operational Amplifier | 获取价格 | |
ICL7650SCBD | RENESAS | Operational Amplifier, 1 Func, 8uV Offset-Max, CMOS, PDSO14 | 获取价格 | |
ICL7650SCPA-1 | INTERSIL | 2MHz, Super Chopper-Stabilized Operational Amplifier | 获取价格 | |
ICL7650SCPA-1Z | INTERSIL | 2MHz, Super Chopper-Stabilized Operational Amplifier | 获取价格 |
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