Data Sheet
Comlinear CLC1002
®
Ultra-Low Noise Amplifier
The COMLINEAR CLC1002(single) is a high-performance, voltage feedback amplifier with ultra-low input voltage noise, 0.6nV/√Hz. The CLC1002
provides 965MHz gain bandwidth product and 170V/μs slew rate making it
well suited for high-speed data acquisition systems requiring high levels of
sensitivity and signal integrity. This COMLINEAR high-performance amplifier
also offers low input offset voltage.
The COMLINEAR CLC1002 is designed to operate from 4V to 12V supplies.
It consumes only 13mA of supply current per channel and offers a power
saving disable pin that disables the amplifier and decreases the supply current to below 225μA. The CLC1002 amplifier operates over the extended
temperature range of -40°C to +125°C.
APPLICATIONS
n Transimpedance amplifiers
n Pre-amplifier
n Low noise signal processing
n Medical instrumentation
n Probe equipment
n Test equipment
n Ultrasound channel amplifier
If larger bandwidth or slew rate is required, a higher minimum stable gain
version is available, the CLC1001 offers a minimum stable gain of 10 with
2.1GHz GBWP and 410V/μs slew rate.
Typical Application - Single Supply Photodiode Amplifier
Comlinear CLC1002 Ultra-Low Noise Amplifier
General Description
FEATURES
n 0.6 nV/√Hz input voltage noise
n 1mV maximum input offset voltage
n 965MHz gain bandwidth product
n Minimum stable gain of 5
n 170V/μs slew rate
n 130mA output current
n -40°C to +125°C operating temperature
range
n Fully specified at 5V and ±5V supplies
n CLC1002: Lead-free SOT23-6
Rev 1G
Ordering Information
Part Number
Package
Pb-Free
RoHS Compliant
Operating Temperature Range
Packaging Method
CLC1002IST6X
SOT23-6
Yes
Yes
-40°C to +125°C
Reel
CLC1002ISO8X
SOIC-8
Yes
Yes
-40°C to +125°C
Reel
CLC1002ISO8
SOIC-8
Yes
Yes
-40°C to +125°C
Rail
Moisture sensitivity level for all parts is MSL-1.
Exar Corporation
48720 Kato Road, Fremont CA 94538, USA
www.exar.com
Tel. +1 510 668-7000 - Fax. +1 510 668-7001
Data Sheet
CLC1002 Pin Assignments
CLC1002 Pin Configuration
1
-V S
2
+IN
3
+
-
6
+VS
5
DIS
-IN
4
SOIC Pin Configuration
Pin Name
Description
1
OUT
Output
2
-VS
Negative supply
3
+IN
Positive input
4
-IN
Negative input
5
DIS
Disable. Enabled if pin is left floating or pulled
above VON, disabled if pin is grounded or pulled
below VOFF.
6
+VS
Positive supply
SOIC Pin Assignments
NC
1
8
DIS
-IN1
2
7
+VS
+IN1
3
6
OUT
-V S
4
5
NC
Pin Name
Description
1
NC
No connect
2
-IN1
Negative input
3
+IN1
Positive input
4
-VS
Negative supply
5
NC
No connect
6
OUT
Output
7
+VS
Positive supply
8
DIS
Disable. Enabled if pin is left floating or pulled
above VON, disabled if pin is grounded or pulled
below VOFF.
©2007-2013 Exar Corporation
2/17
Rev 1G
Rev 1G
Pin No.
Comlinear CLC1002 Ultra-Low Noise Amplifier
OUT
Pin No.
Data Sheet
Absolute Maximum Ratings
The safety of the device is not guaranteed when it is operated above the “Absolute Maximum Ratings”. The device
should not be operated at these “absolute” limits. Adhere to the “Recommended Operating Conditions” for proper device function. The information contained in the Electrical Characteristics tables and Typical Performance plots reflect the
operating conditions noted on the tables and plots.
Supply Voltage
Input Voltage Range
Min
Max
Unit
0
-Vs -0.5V
14
+Vs +0.5V
V
V
Comlinear CLC1002 Ultra-Low Noise Amplifier
Parameter
Reliability Information
Parameter
Junction Temperature
Storage Temperature Range
Lead Temperature (Soldering, 10s)
Package Thermal Resistance
6-Lead SOT23
8-Lead SOIC
Min
Typ
-65
Max
Unit
150
150
260
°C
°C
°C
177
100
°C/W
°C/W
Notes:
Package thermal resistance (qJA), JDEC standard, multi-layer test boards, still air.
ESD Protection
Product
SOT23-6
Human Body Model (HBM)
Charged Device Model (CDM)
2kV
2kV
Rev 1G
Recommended Operating Conditions
Parameter
Min
Operating Temperature Range (CLC1002I)
Operating Temperature Range (CLC1002A)
Supply Voltage Range
-40
-40
4
©2007-2013 Exar Corporation
3/17
Typ
Max
Unit
+85
+125
12
°C
°C
V
Rev 1G
Data Sheet
Electrical Characteristics at +5V
TA = 25°C, Vs = +5V, -Vs = GND, Rf = 100Ω, RL = 500Ω to VS/2, G = 5; unless otherwise noted.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Frequency Domain Response
GBWP
-3dB Gain Bandwidth Product
910
MHz
BWSS
-3dB Bandwidth
G = +5, VOUT = 0.2Vpp
265
MHz
BWLS
Large Signal Bandwidth
G = +5, VOUT = 2Vpp
54
MHz
BW0.1dBSS
0.1dB Gain Flatness Small Signal
G = +5, VOUT = 0.2Vpp
37
MHz
BW0.1dBLS
0.1dB Gain Flatness Large Signal
G = +5, VOUT = 2Vpp
29
MHz
Time Domain Response
tR, tF
Rise and Fall Time
VOUT = 1V step; (10% to 90%)
4.2
ns
tS
Settling Time to 0.1%
VOUT = 1V step
12
ns
OS
Overshoot
VOUT = 1V step
3
%
SR
Slew Rate
4V step
160
V/µs
Distortion/Noise Response
HD2
2nd Harmonic Distortion
1Vpp, 10MHz
-72
dBc
HD3
3rd Harmonic Distortion
1Vpp, 10MHz
-74
dBc
THD
Total Harmonic Distortion
1Vpp, 10MHz
-70
dB
en
Input Voltage Noise
> 100kHz
0.6
nV/√Hz
in
Input Current Noise
> 100kHz
4.2
pA/√Hz
DC Performance
Input Offset Voltage
0.1
mV
dVIO
Average Drift
2.7
µV/°C
Ib
Input Bias Current
28
µA
dIb
Average Drift
46
nA/°C
Io
Input Offset Current
0.1
µA
PSRR
Power Supply Rejection Ratio
DC
83
dB
AOL
Open-Loop Gain
VOUT = VS / 2
80
dB
IS
Supply Current
per channel
12.5
mA
Disable Characteristics
tON
Turn On Time
tOFF
Turn Off Time
OFFISO
Off Isolation
OFFCOUT
Off Output Capacitance
VOFF
Power Down Voltage
VON
ISD
1V step, 1% settling
2Vpp, 5MHz
80
ns
220
ns
73
dB
5.8
pF
Disabled if DIS pin is grounded or pulled below VOFF
Disabled if DIS < 1.5
V
Enable Voltage
Enabled if DIS pin is floating or pulled above VON
Enabled if DIS > 3
V
Disable Supply Current
No Load, DIS pin tied to ground
130
µA
Non-inverting
4.2
MΩ
2
pF
0.8 to
5.1
V
94
dB
RL = 500Ω
0.97 to
4
V
RL = 2kΩ
0.96 to
4.1
V
±125
mA
±150
mA
Input Characteristics
RIN
Input Resistance
CIN
Input Capacitance
CMIR
Common Mode Input Range
CMRR
Common Mode Rejection Ratio
DC , Vcm=1.5V to 4V
Output Characteristics
VOUT
Output Voltage Swing
IOUT
Output Current
ISC
Short-Circuit Output Current
VOUT = VS / 2
Notes:
1. 100% tested at 25°C
©2007-2013 Exar Corporation
4/17
Rev 1G
Rev 1G
VIO
Comlinear CLC1002 Ultra-Low Noise Amplifier
G = +21, VOUT = 0.2Vpp
Data Sheet
Electrical Characteristics at ±5V
TA = 25°C, Vs = ±5V, Rf = 100Ω, RL = 500Ω , G = 5; unless otherwise noted.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Frequency Domain Response
GBWP
-3dB Gain Bandwidth Product
965
MHz
BWSS
-3dB Bandwidth
G = +5, VOUT = 0.2Vpp
290
MHz
BWLS
Large Signal Bandwidth
G = +5, VOUT = 2Vpp
61
MHz
BW0.1dBSS
0.1dB Gain Flatness Small Signal
G = +5, VOUT = 0.2Vpp
45
MHz
BW0.1dBLS
0.1dB Gain Flatness Large Signal
G = +5, VOUT = 2Vpp
32
MHz
Time Domain Response
tR, tF
Rise and Fall Time
VOUT = 1V step; (10% to 90%)
3.8
ns
tS
Settling Time to 0.1%
VOUT = 1V step
12
ns
OS
Overshoot
VOUT = 1V step
2
%
SR
Slew Rate
2V step
170
V/µs
Distortion/Noise Response
HD2
2nd Harmonic Distortion
2Vpp, 10MHz
-75
dBc
HD3
3rd Harmonic Distortion
2Vpp, 10MHz
-66
dBc
THD
Total Harmonic Distortion
2Vpp, 5MHz
-65.5
dB
en
Input Voltage Noise
> 100kHz
0.6
nV/√Hz
in
Input Current Noise
> 100kHz
4.2
pA/√Hz
DC Performance
VIO
dVIO
Ib
Input Offset Voltage(1)
-1
0.5
Average Drift
1
4.3
Input Bias Current (1)
-60
30
mV
µV/°C
60
44
µA
Average Drift
Io
Input Offset Current
PSRR
Power Supply Rejection Ratio
DC
78
83
AOL
Open-Loop Gain (1)
VOUT = VS / 2
70
83
IS
Supply Current (1)
per channel
13
1V step, 1% settling
115
ns
210
ns
nA/°C
0.3
(1)
6
µA
dB
dB
16
mA
Disable Characteristics
tON
Turn On Time
tOFF
Turn Off Time
OFFISO
Off Isolation
OFFCOUT
Off Output Capacitance
VOFF
Power Down Voltage
VON
ISD
2Vpp, 5MHz
73
dB
5.7
pF
Disabled if DIS pin is grounded or pulled below VOFF
Disabled if DIS < 1.3
V
Enable Voltage
Enabled if DIS pin is floating or pulled above VON
Enabled if DIS > 3
Disable Supply Current (1)
No Load, DIS pin tied to ground
180
V
225
µA
Input Characteristics
RIN
Input Resistance
CIN
Input Capacitance
CMIR
Common Mode Input Range
CMRR
Common Mode Rejection Ratio (1)
Non-inverting
DC , Vcm=-3.5V to 4V
9.4
MΩ
1.82
pF
-4.3 to 5
V
75
90
dB
-3.3
±4
Output Characteristics
VOUT
Output Voltage Swing
IOUT
Output Current
ISC
Short-Circuit Output Current
RL = 500Ω (1)
RL = 2kΩ
VOUT = VS / 2
3.6
V
±4
V
±130
mA
±165
mA
Notes:
1. 100% tested at 25°C
©2007-2013 Exar Corporation
5/17
Rev 1G
Rev 1G
dIb
Comlinear CLC1002 Ultra-Low Noise Amplifier
G = +21, VOUT = 0.2Vpp
Data Sheet
Typical Performance Characteristics
TA = 25°C, Vs = ±5V, Rf = 100Ω, RL = 500Ω , G = 5; unless otherwise noted.
Non-Inverting Frequency Response
Inverting Frequency Response
Normalized Gain (dB)
Normalized Gain (dB)
3
0
G = +5
-3
G = +10
G = +20
-6
0
G = -5
-3
G = -10
G = -20
-6
VOUT = 0.2Vpp
VOUT = 0.2Vpp
-9
-9
0.1
1
10
100
1000
0.1
1
10
Frequency (MHz)
100
1000
Frequency (MHz)
Frequency Response vs. CL
Frequency Response vs. RL
3
3
Normalized Gain (dB)
0
CL = 100pF
Rs = 12Ω
-3
CL = 47pF
Rs = 20Ω
CL = 22pF
Rs = 30Ω
-6
VOUT = 0.2Vpp
0
Rl = 1K
Rl = 2K
Rl = 5K
-3
Rev 1G
Normalized Gain (dB)
CL = 470pF
Rs = 4.3Ω
CL = 10pF
Rs = 43Ω
VOUT = 0.2Vpp
-9
-6
0.1
1
10
100
1000
0.1
1
Frequency (MHz)
0
300
-3dB Bandwidth (MHz)
Normalized Gain (dB)
350
VOUT = 4Vpp
-2
VOUT = 3Vpp
-3
100
1000
-3dB Bandwidth vs. Output Voltage
1
-1
10
Frequency (MHz)
Frequency Response vs. VOUT
VOUT = 2Vpp
-4
-5
250
200
150
100
50
-6
-7
0
0.1
1
10
100
1000
0.0
Frequency (MHz)
©2007-2013 Exar Corporation
1.0
2.0
3.0
4.0
VOUT (VPP)
6/17
Comlinear CLC1002 Ultra-Low Noise Amplifier
3
Rev 1G
Data Sheet
Typical Performance Characteristics
TA = 25°C, Vs = ±5V, Rf = 100Ω, RL = 500Ω , G = 5; unless otherwise noted.
Non-Inverting Frequency Response at VS = 5V
Inverting Frequency Response at VS = 5V
Normalized Gain (dB)
Normalized Gain (dB)
3
0
G = +5
G = +10
-3
G = +20
-6
0
G = -5
-3
G = -10
G = -20
-6
VOUT = 0.2Vpp
VOUT = 0.2Vpp
-9
-9
0.1
1
10
100
1000
0.1
1
Frequency (MHz)
10
100
1000
Frequency (MHz)
Frequency Response vs. CL at VS = 5V
Frequency Response vs. RL at VS = 5V
3
3
Normalized Gain (dB)
0
CL = 100pF
Rs = 13Ω
-3
CL = 47pF
Rs = 20Ω
CL = 22pF
Rs = 33Ω
-6
VOUT = 0.2Vpp
0
Rl = 1K
Rl = 2K
Rl = 5K
-3
Rev 1G
Normalized Gain (dB)
CL = 470pF
Rs = 4.3Ω
CL = 10pF
Rs = 50Ω
VOUT = 0.2Vpp
-9
-6
0.1
1
10
100
1000
0.1
1
Frequency (MHz)
0
300
-3dB Bandwidth (MHz)
Normalized Gain (dB)
350
VOUT = 2Vpp
-2
VOUT = 1.5Vpp
-3
100
1000
-3dB Bandwidth vs. Output Voltage at VS = 5V
1
-1
10
Frequency (MHz)
Frequency Response vs. VOUT at VS = 5V
VOUT = 1Vpp
-4
-5
250
200
150
100
50
-6
-7
0
0.1
1
10
100
1000
0.0
Frequency (MHz)
©2007-2013 Exar Corporation
0.5
1.0
1.5
2.0
VOUT (VPP)
7/17
Comlinear CLC1002 Ultra-Low Noise Amplifier
3
Rev 1G
Data Sheet
Typical Performance Characteristics - Continued
TA = 25°C, Vs = ±5V, Rf = 100Ω, RL = 500Ω , G = 5; unless otherwise noted.
Input Voltage Noise at VS = 5V
2.8
2.6
2.6
2.4
2.4
Input Voltage Noise (nV/√Hz)
2.8
2.2
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
2.2
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
0
0.0001
0.001
0.01
0.1
1
10
0.0001
0.001
0.01
Frequency (MHz)
Input Voltage Noise (>10kHz)
1
10
Input Voltage Noise at VS = 5V (>10kHz)
0.9
0.85
0.85
Input Voltage Noise (nV/√Hz)
0.9
0.8
0.75
0.7
0.65
0.6
0.55
0.8
0.75
0.7
0.65
Rev 1G
Input Voltage Noise (nV/√Hz)
0.1
Frequency (MHz)
0.6
0.55
0.5
0.5
0.01
0.1
10
10
1
0.01
Frequency (MHz)
0.1
1
10
10
Frequency (MHz)
ROUT vs. Frequency
ROUT (Ω)
10
1
0.1
0.01
0.001
0.01
0.1
1
10
100
Frequency (MHz)
©2007-2013 Exar Corporation
8/17
Comlinear CLC1002 Ultra-Low Noise Amplifier
Input Voltage Noise (nV/√Hz)
Input Voltage Noise
Rev 1G
Data Sheet
Typical Performance Characteristics - Continued
TA = 25°C, Vs = ±5V, Rf = 100Ω, RL = 500Ω , G = 5; unless otherwise noted.
2nd Harmonic Distortion vs. RL
3rd Harmonic Distortion vs. RL
-55
-65
RL = 500Ω
Distortion (dBc)
Distortion (dBc)
-65
-75
-85
RL = 1kΩ
RL = 500Ω
-75
-85
-95
RL = 1kΩ
-95
VOUT = 1Vpp
VOUT = 1Vpp
-105
-105
5
10
15
20
5
10
Frequency (MHz)
2nd Harmonic Distortion vs. VOUT
-45
-50
-50
-55
Distortion (dBc)
-60
-65
-70
-75
-80
-65
-70
-75
-80
-85
10MHz
-90
-95
-95
RL = 500Ω
-100
0.5
0.75
RL = 500Ω
-100
1
1.25
1.5
1.75
2
2.25
2.5
0.5
0.75
Output Amplitude (Vpp)
1
1.25
1.5
1.75
2
2.25
2.5
Output Amplitude (Vpp)
2nd Harmonic Distortion vs. Gain
3rd Harmonic Distortion vs. Gain
-50
-50
-55
-55
AV+20
-65
-70
-75
AV+10
-80
-65
-70
-75
AV+5
-80
AV+5
VOUT = 1Vpp
-85
AV+20
-60
Distortion (dBc)
-60
Distortion (dBc)
5MHz
10MHz
-90
5MHz
Rev 1G
Distortion (dBc)
20MHz
-55
20MHz
-85
20
3rd Harmonic Distortion vs. VOUT
-45
-60
15
Frequency (MHz)
AV+10
VOUT = 1Vpp
-85
RL = 500Ω
-90
RL = 500Ω
-90
5
Comlinear CLC1002 Ultra-Low Noise Amplifier
-55
10
15
20
5
Frequency (MHz)
©2007-2013 Exar Corporation
10
15
20
Frequency (MHz)
9/17
Rev 1G
Data Sheet
Typical Performance Characteristics - Continued
TA = 25°C, Vs = ±5V, Rf = 100Ω, RL = 500Ω , G = 5; unless otherwise noted.
2nd Harmonic Distortion vs. RL at VS = 5V
3rd Harmonic Distortion vs. RL at VS = 5V
-55
RL = 500Ω
RL = 500Ω
-65
Distortion (dBc)
Distortion (dBc)
-65
-75
RL = 1kΩ
-85
-75
RL = 1kΩ
-85
-95
-95
VOUT = 1Vpp
VOUT = 1Vpp
-105
-105
5
10
15
20
5
10
Frequency (MHz)
2nd Harmonic Distortion vs. VOUT at VS = 5V
-45
-50
-50
-55
Distortion (dBc)
-60
-65
-70
-75
10MHz
-85
-65
-70
-75
-80
-85
5MHz
-90
-95
-95
RL = 500Ω
-100
0.5
0.75
RL = 500Ω
-100
1
1.25
1.5
1.75
2
2.25
2.5
0.5
0.75
Output Amplitude (Vpp)
1
1.25
1.5
1.75
2
2.25
2.5
Output Amplitude (Vpp)
2nd Harmonic Distortion vs. Gain at VS = 5V
3rd Harmonic Distortion vs. Gain Freq at VS = 5V
-50
-50
-55
-55
AV+20
-60
AV+10
-65
-70
-75
AV+20
-60
Distortion (dBc)
Distortion (dBc)
5MHz
10MHz
-90
Rev 1G
Distortion (dBc)
20MHz
-55
20MHz
-80
20
3rd Harmonic Distortion vs. VOUT at VS = 5V
-45
-60
15
Frequency (MHz)
AV+5
-80
-65
-70
AV+5
-75
AV+10
-80
VOUT = 1Vpp
-85
-90
5
VOUT = 1Vpp
-85
RL = 500Ω
RL = 500Ω
-90
10
15
20
5
Frequency (MHz)
©2007-2013 Exar Corporation
10
15
20
Frequency (MHz)
10/17
Comlinear CLC1002 Ultra-Low Noise Amplifier
-55
Rev 1G
Data Sheet
Typical Performance Characteristics - Continued
TA = 25°C, Vs = ±5V, Rf = 100Ω, RL = 500Ω , G = 5; unless otherwise noted.
Small Signal Pulse Response
Small Signal Pulse Response at VS = 5V
2.6
0.05
2.55
Voltage (V)
0.1
Voltage (V)
2.65
0
2.5
-0.05
2.45
-0.1
2.4
-0.15
2.35
0
50
100
150
200
0
50
100
Large Signal Pulse Response
200
Large Signal Pulse Response at VS = 5V
3
4
2
3.5
1
3
Voltage (V)
Voltage (V)
150
Time (ns)
Time (ns)
0
2.5
2
-2
1.5
-3
Rev 1G
-1
1
0
50
100
150
200
0
50
100
Time (ns)
150
200
Time (ns)
Enable Response
Disable Response
5.5
1.5
5.5
1.5
Disable
Enable
4.5
4.5
1.5
Disable Voltage (V)
0.5
Output
3.5
Output
2.5
0.5
1.5
0
Output Voltage (V)
2.5
1
Output Voltage (V)
Enable Voltage (V)
1
3.5
0
0.5
0.5
-0.5
-0.5
-50
0
50
100
150
-0.5
200
-100
Time (ns)
©2007-2013 Exar Corporation
-0.5
0
100
200
300
400
Time (ns)
11/17
Comlinear CLC1002 Ultra-Low Noise Amplifier
0.15
Rev 1G
Data Sheet
Typical Performance Characteristics - Continued
TA = 25°C, Vs = ±5V, Rf = 100Ω, RL = 500Ω , G = 5; unless otherwise noted.
Enable Response at VS = 5V
Disable Response at VS = 5V
1.5
5.5
1.5
Disable
Enable
4.5
4.5
0.5
Output
1.5
Disable Voltage (V)
2.5
1
3.5
Output
2.5
0.5
1.5
0
0
0.5
0.5
-0.5
-0.5
-50
0
50
100
150
-0.5
200
-0.5
-100
0
100
Time (ns)
300
400
Off Isolation at VS = 5V
-40
-45
-45
-50
-50
-55
-55
Off Isolation (dB)
-40
-60
-65
-70
-75
-80
-60
-65
-70
-75
Rev 1G
Off Isolation (dB)
200
Time (ns)
Off Isolation
-80
-85
-85
-90
-90
VOUT = 2Vpp
-95
VOUT = 2Vpp
-95
1
10
100
1
10
Frequency (MHz)
PSRR vs. Frequency
100
80
80
60
60
PSRR (dB)
100
40
20
40
20
0
0.001
100
Frequency (MHz)
CMRR vs. Frequency
CMRR (dB)
Output Voltage (V)
3.5
Output Voltage (V)
Enable Voltage (V)
1
0
0.01
0.1
1
10
100
0.001
Frequency (MHz)
©2007-2013 Exar Corporation
0.01
0.1
1
10
100
Frequency (MHz)
12/17
Comlinear CLC1002 Ultra-Low Noise Amplifier
5.5
Rev 1G
Data Sheet
Application Information
input referred noise also increases.
Basic Operation
3
6.8μF
Input Referred Noise (nV/rtHz)
+Vs
2.75
2.5
G = +5
2.25
G = +11
2
1.75
G = +21
1.5
1.25
1
0.75
Input
0.1μF
+
0.5
100
Output
-
RL
0.1μF
Rg
Figure 3: Input Referred Voltage Noise vs. Rf and Rg
Rf
6.8μF
G = 1 + (Rf/Rg)
-Vs
1000
Rf (Ohms)
The noise caused by a resistor is modeled with either a
voltage source in series with the resistance:
Figure 1. Typical Non-Inverting Gain Circuit
+Vs
R1
Rg
Or a current source in parallel with it:
iR =
0.1μF
+
Output
0.1μF
6.8μF
-Vs
RL
Rf
G = - (Rf/Rg)
4kT
R
Rev 1G
Input
6.8μF
4kTR
Comlinear CLC1002 Ultra-Low Noise Amplifier
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.
Op amp noise is modeled with three noise sources, en, in
and ii. These three sources are analogous to the DC input
voltage and current errors Vos, Ibn and Ibi.
For optimum input offset
voltage set R1 = Rf || Rg
Figure 2. Typical Inverting Gain Circuit
The noise models must be analyzed in-circuit to determine
the effect on the op amp output noise.
Achieving Low Noise in an Application
Making full use of the low noise of the CLC1002 requires
careful consideration of resistor values. The feedback and
gain set resistors (Rf and Rg) and the non-inverting source
impedance (Rsource) all contribute noise to the circuit and
can easily dominate the overall noise if their values are
too high. The datasheet is specified with an Rg of 25Ω, at
which point the noise from Rf and Rg is about equal to the
noise from the CLC1002. Lower value resistors could be
used at the expense of more distortion.
Figure 3 shows total input voltage noise (amp+resistors)
versus Rf and Rg. As the value of Rf increases, the total
©2007-2013 Exar Corporation
Since noise is statistical in nature rather than a continuous
signal, the set of noise sources in circuit add in an RMS
(root mean square) fashion rather than in a linear fashion.
For uncorrelated noise sources, this means you add the
squares of the noise voltages. A typical non-inverting
application (see figure 1) results in the following noise at
the output of the op amp:
e2o
=
en2
1+
Rf
Rg
2
2
+ in Rs
2
1+
Rf
Rg
2
+ ii2R2f op amp noise terms e
op amp noise terms en, in and ii
13/17
Rev 1G
Data Sheet
in figure 3 would be calculated as:
2
+ eRs
Rf
2
Rf
+ e2Rg
Rg
RL || (Rf + Rg)
2
+ e2Rf
Rg
(VLOAD)RMS = VPEAK / √2
( ILOAD)RMS = ( VLOAD)RMS / Rloadeff
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 (ӨJA) is used along with the total die power
dissipation.
TJunction = TAmbient + (ӨJA × PD)
Where TAmbient is the temperature of the working environment.
In order to determine PD, the power dissipated in the load
needs to be subtracted from the total power delivered by
the supplies.
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 4 shows the maximum safe power dissipation in the
package vs. the ambient temperature for the packages
available.
2.5
Power delivered to a purely resistive load is:
Pload = ((VLOAD)RMS2)/Rloadeff
The effective load resistor (Rloadeff) will need to include
the effect of the feedback network. For instance, Rloadeff
©2007-2013 Exar Corporation
1.5
SOT23-6
1
0.5
-40
-20
0
20
40
60
80
100
120
Ambient Temperature (°C)
Supply power is calculated by the standard power
equation.
Vsupply = VS+ - VS-
SOIC-8
0
PD = Psupply - Pload
Psupply = Vsupply × IRMS supply
2
Figure 4. Maximum Power Derating
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 5.
14/17
Rev 1G
Rev 1G
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 Dissipation (W)
Power Dissipation
Comlinear CLC1002 Ultra-Low Noise Amplifier
external resistor noiseThese
terms measurements
for Rs, Rg and Rf
are basic and are relatively easy to
perform with standard lab equipment. For design purposes
however, prior knowledge of actual signal levels and load
external resistor noise terms for RS, Rg and Rf
impedance is needed to determine the dissipated power.
Here, PD can be found from
High source impedances are sometimes unavoidable, but
PD = PQuiescent + PDynamic - PLoad
they increase noise from the source impedance and also
Quiescent power can be derived from the specified IS
make the circuit more sensitive to the op amp current
values along with known supply voltage, VSupply. Load
noise. Analyze all noise sources in the circuit, not just the
power can be calculated as above with the desired signal
op amp itself, to achieve low noise in your application.
amplitudes using:
1+
Data Sheet
3
+
Rs
-
Output
CL
2
4
RL
Figure 5. Addition of RS for Driving Capacitive Loads
Table 1 provides the recommended RS for various
capacitive loads. The recommended RS values result in
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