Exar CLC2023 Dual, low distortion, low offset, rrio amplifier Datasheet

CLC2023
Dual, Low Distortion, Low Offset, RRIO Amplifier
General Description
The CLC2023 is a dual channel, high-performance, voltage feedback
amplifier with low input voltage noise and ultra low distortion. The CLC2023
offers 6mV maximum input offset voltage, 3.5nV/√Hz broadband input
voltage noise, and 0.00005% THD at 1kHz. It also provides 55MHz gain
bandwidth product and 12V/μs slew rate making them well suited for
applications requiring precision DC performance and high AC performance.
This high-performance amplifier also offers a rail-to-rail input and output,
simplifying single supply designs and offering larger dynamic range
possibilities. The input range extends beyond the rails by 300mV.
The CLC2023 is designed to operate from 2.5V to 12V supplies and
operate over the extended temperature range of -40°C to +125°.
FE ATU R E S
■■ 6mV maximum input offset voltage
■■ 0.00005% THD at 1kHz
■■ 5.3nV/√Hz input voltage noise > 10kHz
■■ -90dB/-85dB HD2/HD3 at 100kHz, R = 100Ω
L
■■ <-100dB HD2 and HD3 at 10kHz, R = 1kΩ
L
■■ Rail-to-rail input and output
■■ 55MHz unity gain bandwidth
■■ 12V/μs slew rate
■■ -40°C to +125°C operating temperature
range
■■ Fully specified at 3 and ±5V supplies
■■ CLC2023: ROHS compliant MSOP-8,
SOIC-8 package options
A P P LICATION S
■■ Active filters
■■ Sensor interface
■■ HIgh-speed transducer amp
■■ Medical instrumentation
■■ Probe equipment
■■ Test equipment
■■ Smoke detectors
■■ Hand-held analytic instruments
■■ Current sense applications
Ordering Information - back page
Crosstalk vs. Frequency
Typical Application
-60
+2.7
-65
6.8μF
+
Crosstalk (dB)
-70
0.1μF
In
+ ½
CLC2023
RIN
Out
-80
-85
-90
ROUT
-
-75
-95
Rf
Rg
© 2007-2014 Exar Corporation -100
0.01
Vs = +/- 5V, RL = 150Ω, VOUT = 2Vpp
0.1
1
Frequency (MHz)
1 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Absolute Maximum Ratings
Operating Conditions
Stresses beyond the limits listed below may cause
permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect
device reliability and lifetime.
Supply Voltage Range.................................................. 2.5V to 12V
Operating Temperature Range................................-40°C to 125°C
Junction Temperature............................................................ 150°C
Storage Temperature Range....................................-65°C to 150°C
Lead Temperature (Soldering, 10s).......................................260°C
VS.................................................................................. 0V to +14V
VIN............................................................. -VS - 0.5V to +VS +0.5V
Package Thermal Resistance
θJA (MSOP-8)................................................................... 200°C/W
θJA (SOIC-8)......................................................................150°C/W
Package thermal resistance (θJA), JEDEC standard, multi-layer
test boards, still air.
© 2007-2014 Exar Corporation 2 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Electrical Characteristics at +3V
TA = 25°C, VS = +3V, Rf = 1kΩ, RL = 1kΩ to VS/2; G = 2; unless otherwise noted.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Frequency Domain Response
GBWP
-3dB Gain Bandwidth Product
G = 10, VOUT = 0.05Vpp
31
MHz
UGBW
Unity Gain Bandwidth
VOUT = 0.05Vpp, Rf = 0
50
MHz
BWSS
-3dB Bandwidth
VOUT = 0.05Vpp
24
MHz
BWLS
Large Signal Bandwidth
VOUT = 2Vpp
3.3
MHz
tR, tF
Rise and Fall Time
VOUT = 2V step; (10% to 90%)
150
ns
tS
Settling Time to 0.1%
VOUT = 2V step
78
ns
OS
Overshoot
VOUT = 2V step
0.3
%
SR
Slew Rate
2V step
11
V/μs
2Vpp, 10kHz, RL = 1kΩ
-98
dBc
2Vpp, 100kHz, RL = 100Ω
-85
dBc
2Vpp, 10kHz, RL = 1kΩ
-95
dBc
2Vpp, 100kHz, RL = 100Ω
-81
dBc
0.0005
%
>10kHz
5.5
nV/√Hz
>100kHz
3.9
nV/√Hz
1MHz
70
dB
Time Domain
Distortion/Noise Response
HD2
2nd Harmonic Distortion
HD3
3rd Harmonic Distortion
THD
Total Harmonic Distortion
en
Input Voltage Noise
XTALK
Crosstalk
1Vpp, 1kHz, G = 1, RL = 2kΩ
DC Performance
VIO
dVIO
IB
dIB
Input Offset Voltage
Average Drift
Input Bias Current
Average Drift
0.088
mV
1.3
μV/°C
-0.340
μA
0.8
nA/°C
0.2
μA
dB
IOS
Input Offset Current
PSRR
Power Supply Rejection Ratio
DC
100
AOL
Open Loop Gain
VOUT = VS / 2
104
dB
IS
Supply Current
per channel
1.85
mA
30
MΩ
1.1
pF
Input Characteristics
RIN
Input Resistance
CIN
Input Capacitance
CMIR
Common Mode Input Range
CMRR
Common Mode Rejection Ratio
Non-inverting, G = 1
DC, VCM = 0.5V to 2.5V
-0.3 to 3.3
V
75
dB
Output Characteristics
VOUT
Output Swing
IOUT
Output Current
ISC
Short Circuit Current
RL = 1kΩ
0.085 to
2.80
0.04 to
2.91
+57, -47
mA
VOUT = VS / 2
+65, -52
mA
RL = 150Ω
© 2007-2014 Exar Corporation 3 / 18
V
V
exar.com/CLC2023
Rev 1D
CLC2023
Electrical Characteristics at ±5V
TA = 25°C, VS = ±5V, Rf = 1kΩ, RL = 1kΩ to GND; G = 2; unless otherwise noted.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Frequency Domain Response
GBWP
-3dB Gain Bandwidth Product
G = 10, VOUT = 0.05Vpp
35
MHz
UGBW
Unity Gain Bandwidth
VOUT = 0.05Vpp, Rf = 0
55
MHz
BWSS
-3dB Bandwidth
VOUT = 0.05Vpp
25
MHz
BWLS
Large Signal Bandwidth
VOUT = 2Vpp
3.6
MHz
tR, tF
Rise and Fall Time
VOUT = 2V step; (10% to 90%)
125
ns
tS
Settling Time to 0.1%
VOUT = 2V step
80
ns
OS
Overshoot
VOUT = 2V step
0.3
%
SR
Slew Rate
4V step
12
V/μs
2Vpp, 10kHz, RL = 1kΩ
-125
dBc
2Vpp, 100kHz, RL = 100Ω
-90
dBc
2Vpp, 10kHz, RL = 1kΩ
-127
dBc
2Vpp, 100kHz, RL = 100Ω
-85
dBc
0.00005
%
>10kHz
5.3
nV/√Hz
>100kHz
3.5
nV/√Hz
1MHz
70
dB
Time Domain
Distortion/Noise Response
HD2
2nd Harmonic Distortion
HD3
3rd Harmonic Distortion
THD
Total Harmonic Distortion
en
Input Voltage Noise
XTALK
Crosstalk
1Vpp, 1kHz, G = 1, RL = 2kΩ
DC Performance
VIO
dVIO
IB
dIB
Input Offset Voltage
-6
Average Drift
0.050
6
1.3
Input Bias Current
-2.6
Average Drift
-0.30
2.6
0.85
0.2
mV
μV/°C
μA
nA/°C
IOS
Input Offset Current
0.7
μA
PSRR
Power Supply Rejection Ratio
DC
82
100
AOL
Open Loop Gain
VOUT = VS / 2
95
115
IS
Supply Current
per channel
2.2
Non-inverting, G = 1
30
MΩ
1
pF
dB
dB
2.75
mA
Input Characteristics
RIN
Input Resistance
CIN
Input Capacitance
CMIR
Common Mode Input Range
CMRR
Common Mode Rejection Ratio
DC, VCM = -3V to 3V
70
±5.3
V
85
dB
Output Characteristics
VOUT
Output Swing
RL = 150Ω
RL = 1kΩ
IOUT
Output Current
ISC
Short Circuit Current
-4.7
VOUT = VS / 2
© 2007-2014 Exar Corporation 4 / 18
-4.826 to
4.534
-4.93 to
4.85
V
4.7
V
+60, -48
mA
+65, -52
mA
exar.com/CLC2023
Rev 1D
CLC2023
CLC2023 Pin Configuration
CLC2023 Pin Assignments
MSOP-8 / SOIC-8
MSOP-8 / SOIC-8
OUT1
1
-IN1
2
+IN1
3
-Vs
4
8
+
+
+Vs
7
OUT2
6
-IN2
5
+IN2
© 2007-2014 Exar Corporation Pin No.
Pin Name
1
OUT1
2
-IN1
Negative input, channel 1
3
+IN1
Positive input, channel 1
4
-VS
5
+IN2
Positive input, channel 2
6
-IN2
Negative input, channel 2
7
OUT2
8
+VS
5 / 18
Description
Output, channel 1
Negative supply
Output, channel 2
Positive supply
exar.com/CLC2023
Rev 1D
CLC2023
Typical Performance Characteristics
TA = 25°C, VS = ±5V, Rf = 1kΩ, RL = 1kΩ, G = 2; unless otherwise noted.
Non-Inverting Frequency Response
Inverting Frequency Response
3
1
0
0
-1
Normalized Gain (dB)
Normalized Gain (dB)
G=1
Rf = 0
G=2
-3
G=5
G = 10
-6
G = -1
-2
G = -2
-3
G = -5
G = -10
-4
-5
VOUT = 0.05Vpp
-6
-9
0.1
1
10
VOUT = 0.05Vpp
-7
100
0.1
Frequency (MHz)
1
10
100
Frequency (MHz)
Frequency Response vs. CL
Frequency Response vs. CL without RS
1
4
-1
2
CL = 500pF
Rs = 10Ω
-2
Normalized Gain (dB)
Normalized Gain (dB)
0
CL = 1000pF
Rs = 7.5Ω
-3
CL = 3000pF
Rs = 4Ω
-4
-5
CL = 500pF
0
CL = 300pF
-2
CL = 100pF
-4
CL = 50pF
-6
-6
-7
-8
0.1
1
10
100
CL = 10pF
VOUT = 0.05Vpp
Rs = 0Ω
VOUT = 0.05Vpp
0.1
1
Frequency (MHz)
10
Frequency Response vs. VOUT
Frequency Response vs. RL
3
2
RL = 50Ω
1
0
Normalized Gain (dB)
Normalized Gain (dB)
100
Frequency (MHz)
VOUT = 1Vpp
VOUT = 2Vpp
-3
VOUT = 4Vpp
-6
RL = 150Ω
0
RL = 2.5KΩ
-1
RL = 1KΩ
-2
-3
-4
-5
-9
VOUT = 0.05Vpp
-6
0.1
1
10
100
0.1
Frequency (MHz)
© 2007-2014 Exar Corporation 1
10
100
Frequency (MHz)
6 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Typical Performance Characteristics
TA = 25°C, VS = ±5V, Rf = 1kΩ, RL = 1kΩ, G = 2; unless otherwise noted.
Non-Inverting Frequency Response at VS = 3V
Inverting Frequency Response at VS = 3V
1
3
0
-1
0
Normalized Gain (dB)
Normalized Gain (dB)
G=1
Rf = 0
G=2
-3
G=5
G = 10
G = -1
-2
G = -2
-3
G = -5
G = -10
-4
-5
-6
-6
VOUT = 0.05Vpp
VOUT = 0.05Vpp
-7
-9
0.1
1
10
0.1
100
1
10
Frequency Response vs. VOUT at VS = 3V
Frequency Response vs. RL at VS = 3V
3
2
RL = 50Ω
1
0
Normalized Gain (dB)
Normalized Gain (dB)
100
Frequency (MHz)
Frequency (MHz)
VOUT = 1Vpp
VOUT = 2Vpp
-3
VOUT = 2.5Vpp
-6
RL = 150Ω
0
RL = 2.5KΩ
-1
RL = 1KΩ
-2
-3
-4
-5
-9
VOUT = 0.05Vpp
-6
0.1
1
10
100
0.1
1
Frequency (MHz)
10
100
Frequency (MHz)
-3dB Bandwidth vs. Output Voltage at VS = 3V
-3dB Bandwidth vs. Output Voltage
24
24
21
18
-3dB Bandwidth (MHz)
-3dB Bandwidth (MHz)
21
15
12
9
6
3
18
15
12
9
6
3
0
0.0
0.5
1.0
1.5
2.0
0
2.5
0.0
VOUT (VPP)
© 2007-2014 Exar Corporation 0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
VOUT (VPP)
7 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Typical Performance Characteristics
TA = 25°C, VS = ±5V, Rf = 1kΩ, RL = 1kΩ, G = 2; unless otherwise noted.
Open Loop Gain and Phase vs.
80
0.5
0
-75
PHASE
-150
20
-225
GAIN
0
-300
-20
-375
-40
-450
-60
0.3
PHASE (°)
40
0.4
Vout (V)
60
GAIN (dB)
CMIR
0.1
0
-525
10
100
1,000
10,000
100,000
0.2
-0.1
1,000,000
-6
-4
-2
0
FREQ (KHz)
2
4
6
Vcm(V)
Input Voltage Noise
CMIR at VS = 3V 0.5
14
12
0.4
11
10
0.3
9
Vout (V)
Input Voltage Noise (nV/√Hz)
13
8
7
6
0.2
0.1
5
4
0
3
2
0.0001
0.001
0.01
0.1
-0.1
1
-1
-0.5
0
0.5
Frequency (MHz)
2
2.5
3
3.5
4
PSRR vs. Frequency
110
110
100
100
90
90
PSRR (dB)
CMRR (dB)
1.5
Vcm(V)
CMRR vs. Frequency
80
70
80
70
60
60
50
40
0.001
1
0.01
0.1
1
10
100
50
0.001
1000
1000
Frequency (MHz)
© 2007-2014 Exar Corporation 0.01
0.1
1
10
100
1000
1000
Frequency (MHz)
8 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Typical Performance Characteristics
TA = 25°C, VS = ±5V, Rf = 1kΩ, RL = 1kΩ, G = 2; unless otherwise noted.
2nd Harmonic Distortion vs. RL
3rd Harmonic Distortion vs. RL
-50
-50
-60
RL = 100Ω
RL = 10KΩ
-70
Distortion (dBc)
Distortion (dBc)
-60
-80
-90
RL = 10KΩ
RL = 1KΩ
-70
RL = 100Ω
-80
-90
RL = 500Ω
RL = 1KΩ
RL = 500Ω
-100
-100
VOUT = 2Vpp
VOUT = 2Vpp
-110
-110
100
200
300
400
500
600
700
800
900
1000
100
200
300
400
Frequency (KHz)
2nd Harmonic Distortion vs. VOUT
600
700
800
900
1000
3rd Harmonic Distortion vs. VOUT
-40
-30
-50
-40
-50
-60
RF=RL=1K
Distortion (dBc)
Distortion (dBc)
500
Frequency (KHz)
-70
-80
RF=RL=10K
-100
2.5
3.5
4.5
5.5
-70
-90
FREQ = 500KHz
1.5
RF=RL=1K
-80
RF=RL=10K
-90
0.5
-60
6.5
7.5
8.5
FREQ = 500KHz
-100
9.5
0.5
Output Amplitude (Vpp)
1.5
2.5
3.5
4.5
5.5
6.5
7.5
8.5
9.5
Output Amplitude (Vpp)
THD vs. Frequency
-65
-70
THD (dB)
-75
-80
-85
-90
VOUT = 1Vpp
RL = 1K
AV+1
-95
-100
100
200
300
400
500
600
700
800
900
1000
Frequency (kHz)
© 2007-2014 Exar Corporation 9 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Typical Performance Characteristics
TA = 25°C, VS = ±5V, Rf = 1kΩ, RL = 1kΩ, G = 2; unless otherwise noted.
3rd Harmonic Distortion vs. RL at VS = 3V
-40
-40
-50
-50
RL = 100Ω
-60
-70
-80
RL = 10KΩ
RL = 1KΩ
RL = 500Ω
Distortion (dBc)
Distortion (dBc)
2nd Harmonic Distortion vs. RL at VS = 3V
-60
RL = 100Ω
-70
-80
RL = 500Ω
RL = 10KΩ
RL = 1KΩ
-90
-90
VOUT = 2Vpp
VOUT = 2Vpp
-100
-100
100
200
300
400
500
600
700
800
900
100
1000
200
300
-40
-40
-50
-50
-60
RF=RL=10K
-70
RF=RL=1K
-90
1
1.25
1.5
700
800
900
1000
1.75
2
2.25
-60
RF=RL=10K
-70
-80
RF=RL=1K
FREQ = 500KHz
-100
0.75
600
-90
FREQ = 500KHz
0.5
500
3rd Harmonic Distortion vs. VOUT at VS = 3V
Distortion (dBc)
Distortion (dBc)
2nd Harmonic Distortion vs. VOUT at VS = 3V
-80
400
Frequency (KHz)
Frequency (KHz)
-100
2.5
0.5
Output Amplitude (Vpp)
0.75
1
1.25
1.5
1.75
2
2.25
2.5
Output Amplitude (Vpp)
THD vs. Frequency at VS = 3V
-65
-70
THD (dB)
-75
-80
-85
-90
VOUT = 1Vpp
RL = 1K
AV+1
-95
-100
100
200
300
400
500
600
700
800
900
1000
Frequency (kHz)
© 2007-2014 Exar Corporation 10 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Typical Performance Characteristics
TA = 25°C, VS = ±5V, Rf = 1kΩ, RL = 1kΩ, G = 2; unless otherwise noted.
Small Signal Pulse Response
Small Signal Pulse Response at VS = 3V
0.5
1.6
0.25
1.55
Voltage (V)
1.65
Voltage (V)
0.75
0
-0.25
1.5
1.45
-0.5
1.4
-0.75
0
0.5
1
1.5
1.35
2
0
Time (ns)
1
1.5
2
Time (ns)
Large Signal Pulse Response
Large Signal Pulse Response at VS = 3V
6
3
4
2.5
2
2
Voltage (V)
Voltage (V)
0.5
0
-2
1.5
1
-4
0.5
-6
0
1
2
3
4
5
6
7
8
9
0
10
0
Time (ns)
© 2007-2014 Exar Corporation 0.5
1
1.5
2
Time (ns)
11 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Application Information
Where TAmbient is the temperature of the working
environment.
Basic Information
Figures 1 and 2 illustrate typical circuit configurations for
non-inverting, inverting, and unity gain topologies for dual
supply applications. They show the recommended bypass
capacitor values and overall closed loop gain equations.
+Vs
6.8μF
In order to determine PD, the power dissipated in the load
needs to be subtracted from the total power delivered by the
supplies.
PD = Psupply - Pload
Supply power is calculated by the standard power equation.
Psupply = Vsupply × IRMSsupply
Input
0.1μF
+
Vsupply = VS+ - VSOutput
RL
0.1μF
Rg
6.8μF
-Vs
Power delivered to a purely resistive load is:
Rf
Pload = ((Vload)RMS2)/Rloadeff
G = 1 + (Rf/Rg)
Figure 1: Typical Non-Inverting Gain Circuit
+Vs
R1
Input
Rg
+
The effective load resistor (Rloadeff) will need to include the
effect of the feedback network. For instance,
Rloadeff in Figure 2 would be calculated as:
6.8μF
RL || (Rf + Rg)
0.1μF
These measurements are basic and are relatively easy to
perform with standard lab equipment. For design purposes
however, prior knowledge of actual signal levels and load
impedance is needed to determine the dissipated power.
Here, PD can be found from
Output
RL
0.1μF
6.8μF
-Vs
Rf
G = - (Rf/Rg)
For optimum input offset
voltage set R1 = Rf || Rg
PD = PQuiescent + PDynamic - Pload
Quiescent power can be derived from the specified IS values
along with known supply voltage, Vsupply. Load power can
be calculated as above with the desired signal amplitudes
using:
Figure 2: Typical Inverting Gain Circuit
(Vload)RMS = Vpeak / √2
( Iload)RMS = ( Vload)RMS / Rloadeff
Power Dissipation
Power dissipation should not be a factor when operating
under the stated 500Ω load condition. However, applications
with low impedance, DC coupled loads should be analyzed
to ensure that maximum allowed junction temperature is
not exceeded. Guidelines listed below can be used to verify
that the particular application will not cause the device to
operate beyond it’s intended operating range.
Maximum power levels are set by the absolute maximum
junction rating of 150°C. To calculate the junction
temperature, the package thermal resistance value ThetaJA
(θJA) is used along with the total die power dissipation.
TJunction = TAmbient + (θJA × PD)
© 2007-2014 Exar Corporation The dynamic power is focused primarily within the output
stage driving the load. This value can be calculated as:
PDynamic = (VS+ - Vload)RMS × ( Iload)RMS
Assuming the load is referenced in the middle of the power
rails or Vsupply/2.
Figure 3 shows the maximum safe power dissipation in
the package vs. the ambient temperature for the packages
available.
12 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Overdrive Recovery
Maximum Power Dissipation (W)
1.5
An overdrive condition is defined as the point when either
one of the inputs or the output exceed their specified
voltage range. Overdrive recovery is the time needed for the
amplifier to return to its normal or linear operating point. The
recovery time varies based on whether the input or output
is overdriven and by how much the ranges are exceeded.
The CLC2023 will typically recover in less than 20ns from
an overdrive condition. Figure 5 shows the CLC2023 in an
overdriven condition.
SOIC-8
1
0.5
MSOP-8
3
0
-40
-20
0
20
40
60
80
100
2
VIN = .8Vpp
G=5
120
Ambient Temperature (°C)
2
2
1
Input Voltage (V)
Driving Capacitive Loads
Increased phase delay at the output due to capacitive loading
can cause ringing, peaking in the frequency response, and
possible unstable behavior. Use a series resistance, RS,
between the amplifier and the load to help improve stability
and settling performance. Refer to Figure 4.
1
Input
1
0
0
Output
-1
-1
Output Voltage (V)
Figure 3. Maximum Power Derating
-1
-2
-2
-3
-2
0
0.25
0.5
0.75
1
1.25
1.5
1.75
2
Time (us)
Input
+
Figure 5: Overdrive Recovery
Rs
Rf
Output
CL
RL
Considerations for Offset and Noise Performance
Offset Analysis
Rg
Figure 4. Addition of RS for Driving Capacitive Loads
The CLC2023 is capable of driving up to 300pF directly, with
no series resistance. Directly driving 500pF causes over
4dB of frequency peaking, as shown in the plot on page 6.
Table 1 provides the recommended RS for various capacitive
loads. The recommended RS values result in ≤ 1dB peaking
in the frequency response. The Frequency Response vs.
CL plots, on page 6, illustrate the response of the CLC2023.
There are three sources of offset contribution to consider;
input bias current, input bias current mismatch, and input
offset voltage. The input bias currents are assumed to be
equal with and additional offset current in one of the inputs
to account for mismatch. The bias currents will not affect
the offset as long as the parallel combination of Rf and Rg
matches Rt. Refer to Figure 6.
–
Rt
CL (pF)
RS (Ω)
-3dB BW (MHz)
500
10
27
1000
7.5
20
3000
4
15
Table 1: Recommended RS vs. CL
For a given load capacitance, adjust RS to optimize the
tradeoff between settling time and bandwidth. In general,
reducing RS will increase bandwidth at the expense of
additional overshoot and ringing.
© 2007-2014 Exar Corporation +Vs
Rf
Rg
IN
CLC2023
+
RL
-Vs
Figure 6: Circuit for Evaluating Offset
The first place to start is to determine the source resistance.
If it is very small an additional resistance may need to be
added to keep the values of Rf and Rg to practical levels.
For this analysis we assume that Rt is the total resistance
present on the non-inverting input. This gives us one
equation that we must solve:
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CLC2023
Rt = Rg||Rf
The complete equation can be simplified to:
This equation can be rearranged to solve for Rg:
2
v
o
Rg = (Rt * Rf) / (Rf - Rt)
The other consideration is desired gain (G) which is:
(
2
) ( )
= 3 ∗ 4kT ∗ G ∗ RT + enG
(
+ 2 ∗ in ∗ RT
2
)
It’s easy to see that the effect of amplifier voltage noise
is proportionate to gain and will tend to dominate at large
gains. The other terms will have their greatest impact at
large Rt values at lower gains.
G = (1 + Rf/Rg)
By plugging in the value for Rg we get
Rf = G * Rt
And Rg can be written in terms of Rt and G as follows:
Rg = (G * Rt) / (G - 1)
The complete input offset equation is now only dependent
on the voltage offset and input offset terms given by:
VI OS =
2
2
Layout Considerations
General layout and supply bypassing play major roles in
high frequency performance. Exar has evaluation boards to
use as a guide for high frequency layout and as an aid in
device testing and characterization. Follow the steps below
as a basis for high frequency layout:
( VIO ) + (IOS ∗ RT)
■■
And the output offset is:
VO OS = G ∗
2
2
( V IO ) + (I OS ∗ RT )
Include 6.8µF and 0.1µF ceramic capacitors for power supply
decoupling
■■
Place the 6.8µF capacitor within 0.75 inches of the power pin
■■
Place the 0.1µF capacitor within 0.1 inches of the power pin
■■
■■
Remove the ground plane under and around the part,
especially near the input and output pins to reduce parasitic
capacitance
Minimize all trace lengths to reduce series inductances
Refer to the evaluation board layouts below for more
information.
Noise analysis
The complete equivalent noise circuit is shown in Figure 7.
Rg
Evaluation Board Information
Rf
+–
+–
The following evaluation boards are available to aid in the
testing and layout of these devices:
–
CLC2023
Rg
+–
+
+–
w
+
–
Evaluation Board #
RL
Figure 7: Complete Equivalent Noise Circuit
2
RF
= vorext + en 1 +
RG
2
+ ibp ∗ RT 1 +
RF
RG
2
(
+ ibn ∗ RF
CEB006
CLC2023 in SOIC-8
CEB010
CLC2023 in MSOP-8
Evaluation Board Schematics
The complete noise equation is given by:
2
v
o
Products
2
)
Evaluation board schematics and layouts are shown in
Figures 8-12 These evaluation boards are built for dualsupply operation. Follow these steps to use the board in a
single-supply application:
1. Short -VS to ground.
Where Vorext is the noise due to the external resistors and
is given by:
2
v
o
= en 1 +
RF
RG
2
+ eG ∗
RF
RG
2
2. Use C3 and C4, if the -VS pin of the amplifier is not
directly connected to the ground plane.
2
+ eF
© 2007-2014 Exar Corporation 14 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Figure 10. CEB006 Bottom View
Figure 8. CEB006 & CEB010 Schematic
Figure 11. CEB010 Top View
Figure 9. CEB006 Top View
Figure 12. CEB010 Bottom View
© 2007-2014 Exar Corporation 15 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Mechanical Dimensions
SOIC-8 Package
© 2007-2014 Exar Corporation 16 / 18
exar.com/CLC2023
Rev 1D
CLC2023
MSOP-8 Package
© 2007-2014 Exar Corporation 17 / 18
exar.com/CLC2023
Rev 1D
CLC2023
Ordering Information
Part Number
Package
Green
Operating Temperature Range
Packaging
CLC2023IMP8X
MSOP-8
Yes
-40°C to +125°C
Tape & Reel
CLC2023IMP8MTR
MSOP-8
Yes
-40°C to +125°C
Mini Tape & Reel
CLC2023IMP8EVB
Evaluation Board
N/A
N/A
N/A
CLC2023ISO8X
SOIC-8
Yes
-40°C to +125°C
Tape & Reel
CLC2023ISO8MTR
SOIC-8
Yes
-40°C to +125°C
Mini Tape & Reel
CLC2023ISO8EVB
Evaluation Board
N/A
N/A
N/A
CLC2023 Ordering Information
Moisture sensitivity level for all parts is MSL-1.
Revision History
Revision
1D (ECN 1451-06)
Date
December
2014
Description
Reformat into Exar data sheet template. Updated ordering information table to include MTR and EVB
part numbers. Increased “I” temperature range from +85 to +125°C. Removed “A” temp grade parts,
since “I” is now equivalent. Updated thermal resistance numbers and package outline drawings.
For Further Assistance:
Email: [email protected] or [email protected]
Exar Technical Documentation: http://www.exar.com/techdoc/
Exar Corporation Headquarters and Sales Offices
48760 Kato Road
Tel.: +1 (510) 668-7000
Fremont, CA 94538 - USA
Fax: +1 (510) 668-7001
NOTICE
EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. EXAR Corporation
assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free
of patent infringement. Charts and schedules contained here in are only for illustration purposes and may vary depending upon a user’s specific application. While the information
in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies.
EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected
to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation
receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes all such risks; (c) potential liability of EXAR
Corporation is adequately protected under the circumstances.
Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.
© 2007-2014 Exar Corporation 18 / 18
exar.com/CLC2023
Rev 1D
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