LTC2058
36V, Low Noise Zero-Drift
Operational Amplifier
DESCRIPTION
FEATURES
Supply Voltage Range: 4.75V to 36V
nn Offset Voltage: 5μV (Maximum)
nn Offset Voltage Drift: 0.025μV/°C (Maximum, –40°C
to 125°C)
nn Input Noise Voltage
nn 200nV
P-P, DC to 10Hz (Typ)
nn 9nV/√Hz, 1kHz (Typ)
nn Input Common Mode Range: V– – 0.1V to V+ – 1.5V
nn Rail-to-Rail Output
nn Unity Gain Stable
nn Gain Bandwidth Product: 2.5MHz (Typ)
nn Slew Rate: 1.6V/μs (Typ)
nn A
VOL: 150dB (Typ)
nn PSRR: 150dB (Typ)
nn CMRR: 150dB (Typ)
nn Shutdown Mode
nn
APPLICATIONS
The LTC®2058 is a dual, low noise, zero-drift operational
amplifier that offers precision DC performance over a
wide supply range of 4.75V to 36V. Offset voltage and 1/f
noise are suppressed, allowing this amplifier to achieve
a maximum offset voltage of 5μV and a DC to 10Hz input
noise voltage of 200nVP-P (Typ). The LTC2058’s selfcalibrating circuitry results in low offset voltage drift with
temperature, 0.025μV/°C (Max), and practically zero drift
over time. The amplifier also features an excellent power
supply rejection ratio (PSRR) of 150dB and a common
mode rejection ratio (CMRR) of 150dB (Typ).
The LTC2058 provides rail-to-rail output swing and an
input common mode range that includes the V– rail. In
addition to low offset and noise, this amplifier features
a 2.5MHz (Typ) gain-bandwidth product and a 1.6V/μs
(Typ) slew rate.
Wide supply range, combined with low noise, low offset,
and excellent PSRR and CMRR make the LTC2058 well
suited for high dynamic-range test, measurement, and
instrumentation systems.
High Resolution Data Acquisition
Reference Buffering
nn Test and Measurement
nn Electronic Scales
nn Thermocouple Amplifiers
nn Strain Gauges
nn Low Side Current Sense
nn Automotive Monitors and Control
nn
nn
All registered trademarks and trademarks are the property of their respective owners.
TYPICAL APPLICATION
18-Bit Voltage Output DAC with Software-Selectable Ranges
Output Voltage Noise, ±10V Span, VOUT = 0V
MEASUREMENT BANDWIDTH
10kHz
100kHz
+
½ LTC2058
–
RIN
RCOM
REF
ROFS
RFB
LTC2756
18-BIT DAC WITH SPAN SELECT
VDD
GND
GAIN
ADJUST
VOSADJ
GEADJ
OFFSET
ADJUST
VS = ±15V
DAC SPAN = ±10V
20pF
4
5V
0.1µF
150pF
VOUT NOISE
12μVRMS
80μVRMS
VOUT (5V/DIV)
REF
5V
SPI WITH
READBACK
20V Step Response of DAC I to V
IOUT1
–
IOUT2
+
½ LTC2058
VOUT
15µs/DIV
2058 TA01b
GND
2058 TA01a
Rev 0
Document Feedback
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1
LTC2058
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Total Supply Voltage
(V+ to V–)...............................................................40V
Input Voltage
–IN, +IN.................................... V– – 0.3V to V+ + 0.3V
SD, SDCOM.............................. V– – 0.3V to V+ + 0.3V
Input Current
–IN, +IN............................................................ ±10mA
SD, SDCOM...................................................... ±10mA
Differential Input Voltage
+IN to –IN..............................................................±6V
SD – SDCOM......................................... –0.3V to 5.3V
Output Short-Circuit Duration........................... Indefinite
Operating Temperature Range (Note 2)
LTC2058I..............................................–40°C to 85°C
LTC2058H........................................... –40°C to 125°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................... 300°C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
OUTA 1
–INA 2
+INA 3
9
V–
V– 4
8
V+
7
OUTB
6
–INB
5
+INB
SD
V–
OUTA
GUARD
–INA
+INA
1
2
3
4
5
6
13
V–
12
11
10
9
8
7
SDCOM
V+
OUTB
GUARD
–INB
+INB
S8E PACKAGE
8-LEAD PLASTIC SO
MSE PACKAGE
12-LEAD PLASTIC MSOP
TJMAX = 150°C, θJC = 5°C/W, θJA = 33°C/W
EXPOSED PAD (PIN 9) IS V–, MUST BE SOLDERED TO PCB
TJMAX = 150°C, θJC = 10°C/W, θJA = 40°C/W
EXPOSED PAD (PIN 13) IS V–, MUST BE SOLDERED TO PCB
ORDER INFORMATION
TUBES
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
SPECIFIED TEMPERATURE RANGE
LTC2058IMSE#PBF
LTC2058IMSE#TRPBF
2058
12-Lead Plastic MSOP
–40°C to 85°C
LTC2058HMSE#PBF
LTC2058HMSE#TRPBF
2058
12-Lead Plastic MSOP
–40°C to 125°C
LTC2058IS8E#PBF
LTC2058IS8E#TRPBF
2058
8-Lead Plastic Small Outline
–40°C to 85°C
LTC2058HS8E#PBF
LTC2058HS8E#TRPBF
2058
8-Lead Plastic Small Outline
–40°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Parts ending with PBF are ROHS and WEEE compliant.
For more information on tape and reel specifications, go to: Tape and reel specifications Some packages are available in 500 unit reels through designated
sales channels with #TRMPBF suffix.
Rev 0
2
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LTC2058
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. Unless otherwise noted, VS = ±2.5V; VCM = VOUT = 0V.
SYMBOL
PARAMETER
VOS
Input Offset Voltage (Note 3)
Average Input Offset Voltage Drift (Note 3)
ΔVOS
CONDITIONS
MIN
–40°C to 125°C
l
–40°C to 85°C
–40°C to 125°C
l
l
–40°C to 85°C
–40°C to 125°C
1kHz, CEXT = 0pF
1kHz
DC to 10Hz
l
l
TYP
MAX
UNITS
0.5
5
0.025
μV
μV/°C
30
100
200
4.5
200
200
300
pA
pA
nA
pA
pA
pA
pA/√Hz
nV/√Hz
nVP-P
Ω||pF
Ω||pF
dB
dB
dB
dB
dB
dB
dB
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mA
V/μs
V/μs
MHz
kHz
mA
mA
mA
µA
µA
µA
V
V
V
µA
µA
ΔT
IB
IOS
in
en
enP-P
ZIN
CMRR
PSRR
AVOL
VOL – V–
V+ – VOH
ISC
SRRISE
SRFALL
GBW
fC
IS
VSDL
VSDH
ISD
ISDCOM
Input Bias Current (Notes 4, 5)
Input Offset Current (Notes 4, 5)
Input Noise Current Spectral Density (Note 8)
Input Noise Voltage Spectral Density
Input Noise Voltage
Differential Input Impedance
Common Mode Input Impedance
Common Mode Rejection Ratio (Note 6)
Power Supply Rejection Ratio (Note 6)
Open Loop Voltage Gain (Note 6)
Output Voltage Swing Low
Output Voltage Swing High
Short-Circuit Current
Rising Slew Rate
Falling Slew Rate
Gain Bandwidth Product
Internal Chopping Frequency
Supply Current Per Amplifier
VCM = V – – 0.1V to V+ – 1.5V
–40°C to 85°C
–40°C to 125°C
VS = 4.75V to 36V
–40°C to 125°C
VOUT = V– +0.5V to V+ – 0.3V, RL =1kΩ
–40°C to 125°C
No Load
–40°C to 125°C
ISINK = 1mA
–40°C to 125°C
ISINK = 5mA
–40°C to 85°C
–40°C to 125°C
No Load
–40°C to 125°C
ISOURCE = 1mA
–40°C to 125°C
ISOURCE = 5mA
–40°C to 85°C
–40°C to 125°C
Sourcing/Sinking
AV = –1, RL = 10kΩ
AV = –1, RL = 10kΩ
No Load
–40°C to 85°C
–40°C to 125°C
In Shutdown Mode
–40°C to 85°C
–40°C to 125°C
Shutdown Threshold (SD – SDCOM) Low (Note 7) –40°C to 125°C
Shutdown Threshold (SD – SDCOM) High (Note 7) –40°C to 125°C
SDCOM Voltage Range (Note 7)
–40°C to 125°C
SD Pin Current (Note 7)
–40°C to 125°C, VSD – VSDCOM = 0
SDCOM Pin Current (Note 7)
–40°C to 125°C, VSD – VSDCOM = 0
60
l
l
l
l
123
121
118
140
140
124
120
0.5
9
200
225k||8
1012||20
150
150
150
5
l
55
l
260
l
l
5.5
l
50
l
235
l
l
20/19
31/30
1.6
1.7
2.5
100
0.95
l
l
3
l
l
l
l
l
l
l
2
V–
–1
15
20
150
200
470
750
750
16
20
75
95
315
365
400
1.15
1.4
1.55
4.25
5
0.8
V+ –2V
–0.5
0.75
1.5
Rev 0
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3
LTC2058
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. Unless otherwise noted, VS = ±15V; VCM = VOUT = 0V.
SYMBOL
PARAMETER
VOS
Input Offset Voltage (Note 3)
ΔVOS
Average Input Offset Voltage Drift (Note 3)
CONDITIONS
MIN
TYP
0.5
–40°C to 125°C
l
–40°C to 85°C
–40°C to 125°C
l
l
l
l
MAX
5
UNITS
μV
0.025
μV/°C
100
200
4.5
200
200
300
1
0.5
9
pA
pA
nA
pA
pA
pA
pA/√Hz
pA/√Hz
nV/√Hz
200
nVP-P
225k||13
1012||6
150
31/36
Ω||pF
Ω||pF
dB
dB
dB
dB
dB
dB
dB
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mA
1.6
V/μs
ΔT
IB
Input Bias Current (Note 4, 5)
IOS
Input Offset Current (Note 4, 5)
in
Input Noise Current Spectral Density (Note 8)
en
Input Noise Voltage Spectral Density
–40°C to 85°C
–40°C to 125°C
1kHz, CEXT = 0pF
1kHz, CEXT = 22pF
1kHz
enP-P
Input Noise Voltage
DC to 10Hz
ZIN
Differential Input Impedance
Common Mode Input Impedance
Common Mode Rejection Ratio (Note 6)
30
60
ISC
Short-Circuit Current
VCM = V– – 0.1V to V+ – 1.5V
–40°C to 85°C
–40°C to 125°C
VS = 4.75V to 36V
–40°C to 125°C
VOUT = V– +0.4V to V+ –0.25V, RL = 10kΩ
–40°C to 125°C
No Load
–40°C to 125°C
ISINK = 1mA
–40°C to 125°C
ISINK = 5mA
–40°C to 85°C
–40°C to 125°C
No Load
–40°C to 125°C
ISOURCE = 1mA
–40°C to 125°C
ISOURCE = 5mA
–40°C to 85°C
–40°C to 125°C
Sourcing/Sinking
SRRISE
Rising Slew Rate
AV = –1, RL = 10kΩ
SRFALL
Falling Slew Rate
AV = –1, RL = 10kΩ
1.7
V/μs
GBW
Gain Bandwidth Product
2.5
MHz
fC
Internal Chopping Frequency
100
kHz
IS
Supply Current Per Amplifier
CMRR
PSRR
AVOL
VOL – V–
V+ – VOH
VSDL
Power Supply Rejection Ratio (Note 6)
Open Loop Voltage Gain (Note 6)
Output Voltage Swing Low
Output Voltage Swing High
No Load
–40°C to 85°C
–40°C to 125°C
In Shutdown Mode
–40°C to 85°C
–40°C to 125°C
Shutdown Threshold (SD – SDCOM) Low (Note 7) –40°C to 125°C
l
l
l
l
138
137
135
140
140
137
133
150
150
5
l
55
l
270
l
l
7
l
50
l
235
l
l
20/25
1
l
l
5
l
l
l
15
20
150
200
470
750
750
18
22
75
90
315
365
400
1.2
1.45
1.6
7.5
9
0.8
mA
mA
mA
µA
µA
µA
V
Rev 0
4
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LTC2058
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. Unless otherwise noted, VS = ±15V; VCM = VOUT = 0V.
SYMBOL
PARAMETER
VSDH
CONDITIONS
MIN
Shutdown Threshold (SD – SDCOM) High (Note 7) –40°C to 125°C
l
2
SDCOM Voltage Range (Note 7)
–40°C to 125°C
l
V–
ISD
SD Pin Current (Note 7)
–40°C to 125°C, VSD – VSDCOM = 0
l
–1
ISDCOM
SDCOM Pin Current (Note 7)
–40°C to 125°C, VSD – VSDCOM = 0
l
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC2058I is guaranteed to meet specified performance
from –40°C to 85°C. The LTC2058H is guaranteed to meet specified
performance from –40°C to 125°C.
Note 3: These parameters are guaranteed by design. Thermocouple effects
preclude measurements of these voltage levels during automated testing.
VOS is measured to a limit determined by test equipment capability.
Note 4: These specifications are limited by automated test system
capability. Leakage currents and thermocouple effects reduce test
accuracy. For tighter guaranteed specifications, please contact LTC
Marketing.
TYP
MAX
UNITS
V
V+ –2V
V
–0.5
0.75
µA
1.5
µA
Note 5: Input BIAS current is measured using an equivalent source
impedance of 100MΩ || 51pF.
Note 6: Minimum specifications for these parameters are limited by
the capabilities of the automated test system, which has an accuracy of
approximately 10µV for VOS measurements. For reference, 30V/1µV is
150dB of voltage ratio.
Note 7: MSE package only.
Note 8: Refer to the Application Information section for more details.
Rev 0
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5
LTC2058
TYPICAL PERFORMANCE CHARACTERISTICS
80
N = 160
VS = ±2.5V
µ = 0.130µV
σ = 0.420µV
TA = 25°C
NUMBER OF AMPLIFIERS
60
50
70
NUMBER OF AMPLIFIERS
70
40
30
20
60
50
40
30
20
30
20
5
6 TYPICAL CHANNELS
VS = 5V
TA = 25°C
4
3
30
20
3
2
2
1
1
0
–1
–2
–2
–3
–4
–4
0
–5
4
6
8
10 12 14 16 18 20
VOS TC (nV/°C)
–1
0
1
Input Offset Voltage vs
Supply Voltage
4
–5
5
3
2
1
1
VOS (µV)
2
0
–1
0
–1
–2
–2
–3
–3
–4
–4
0
5
10
15
20 25
VS (V)
30
35
40
10
IB (nA)
3
100
78 TYPICAL CHANNELS
4 VS = ±15V
6 TYPICAL CHANNELS
VCM = VS/2
TA = 25°C
–5
5
10
15
VCM (V)
20
25
30
2058 G06
Input Bias Current vs Temperature
5
4
0
2058 G05
Long-Term Input Offset Voltage
Drift
5
VOS (µV)
3
VCM (V)
2058 G04
–5
2
8 10 12 14 16 18 20
VOS TC (nV/°C)
0
–3
2
6
–1
10
0
4
6 TYPICAL CHANNELS
VS = 30V
TA = 25°C
4
VOS (µV)
VOS (µV)
40
2
Input Offset Voltage vs
Input Common Mode Voltage
5
50
0
2058 G03
Input Offset Voltage vs
Input Common Mode Voltage
N = 160
VS = ±15V
µ = 5.469nV/°C
σ = 1.805nV/°C
60
40
2058 G02
Input Offset Voltage Drift
Distribution
70
50
0
–3 –2.5 –2 –1.5 –1 –0.5 0 0.5 1 1.5 2 2.5 3
VOS (µV)
2058 G01
80
60
10
0
–3 –2.5 –2 –1.5 –1 –0.5 0 0.5 1 1.5 2 2.5 3
VOS (µV)
N = 160
VS = ±2.5V
µ = 3.933nV/°C
σ = 1.318nV/°C
70
10
10
NUMBER OF AMPLIFIERS
80
N = 160
VS = ±15V
µ = 0.194µV
σ = 0.436µV
TA = 25°C
NUMBER OF AMPLIFIERS
80
0
Input Offset Voltage Drift
Distribution
Input Offset Voltage Distribution
Input Offset Voltage Distribution
1 TYPICAL UNIT
VS = ±15V
VCM=0V
1
0.1
0
300
600
900 1200 1500 1800 2100
TIME (HOURS)
2058 G07
2058 G08
0.01
–50 –25
0
25 50 75 100 125 150
TEMPERATURE (°C)
2058 G09
Rev 0
6
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LTC2058
TYPICAL PERFORMANCE CHARACTERISTICS
Input Bias Current vs Input
Common Mode Voltage
Input Bias Current vs Input
Common Mode Voltage
100
100
100
AVERAGE OF 6 TYPICAL CHANNELS
80 VS = 30V
T =25°C
60 A
AVERAGE OF 6 TYPICAL CHANNELS
80 VS = 5V
T =25°C
60 A
60
40
20
20
20
–20
IB (pA)
40
0
0
–20
0
–20
–40
–40
–40
–60
–60
–60
–80
–80
–80
0
1
2
3
4
INPUT–REFERRED VOLTAGE NOISE (100nV/DIV)
VCM (V)
–100
5
0
5
2058 G10
DC to 10Hz Voltage Noise
VS = ±2.5V
2058 G13
1s/DIV
10
15
VCM (V)
20
25
–100
30
IB(+IN)
IB(–IN)
0
5
10
15
2058 G11
DC to 10Hz Voltage Noise
20 25
VS (V)
30
35
40
2058 G12
Input Voltage Noise Spectrum
100
VS = ±2.5V...±15V
AV=+1
VS = ±15V
2058 G14
1s/DIV
INPUT-REFERRED
VOLTAGE NOISE DENSITY (nV/√Hz)
–1
INPUT-REFERRED VOLTAGE NOISE (100nV/DIV)
–100
AVERAGE OF 6 TYPICAL CHANNELS
VCM = VS/2
TA = 25°C
80
40
IB (pA)
IB (pA)
Input Bias Current vs
Supply Voltage
10
1
0.1
1
10
100 1k 10k 100k 1M 10M
FREQUENCY (Hz)
2058 G15
Common Mode Rejection Ratio
vs Frequency
Input Current Noise Spectrum
120
CEXT = 0 pF
TA = 25°C
140
VS = 30V
VCM= VS/2
100
60
40
0.1
0.1
1
10
100
1k
FREQUENCY (Hz)
10k
100k
0
100
80
60
40
20
VS= ±15V
VS= ±2.5V
PSRR+
PSRR–
100
PSRR (dB)
1
VS = 30V
VCM = VS /2
120
80
CMRR (dB)
INPUT–REFERRED
CURRENT NOISE DENSITY (pA/√Hz)
10
Power Supply Rejection Ratio
vs Frequency
20
1k
10k
100k
FREQUENCY (Hz)
1M
10M
2058 G17
2058 G16
0
1
10
100 1k 10k 100k
FREQUENCY (Hz)
1M
10M
2058 G18
Rev 0
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7
LTC2058
TYPICAL PERFORMANCE CHARACTERISTICS
Open Loop Gain vs Frequency
100
VS = ±15V
RL,eff = 10kΩ
50
90
60
GAIN (dB)
20
10
20
0
0
–20
–10
–40
–20
–60
10k
1k
10k
100k
1M
FREQUENCY (Hz)
10M
45
GAIN
0
CL= 0pF
CL= 50pF
CL= 200pF
90
60
PHASE
40
PHASE
40
20
0
–20
–45
10M
2058 G19
45
GAIN
0
CL= 0pF
CL= 50pF
CL= 200pF
–40
100k
1M
FREQUENCY (Hz)
–60
10k
100k
1M
FREQUENCY (Hz)
2058 G21
Shutdown Transient
with Sinusoid Input
Closed Loop Output Impedance
vs Frequency
1k
V S = ±15V, A V = +1, RL = 2kΩ
POWER SUPPLY BYPASS = 10nF
VS = ±2.5V, A V = +1, R L = 2kΩ
POWER SUPPLY BYPASS = 10nF
–45
10M
2058 G20
Shutdown Transient
with Sinusoid Input
135
VS = ±15V
RL= 10kΩ
PHASE (°C)
30
100
80
PHASE (°C)
CLOSED LOOP GAIN (dB)
VS = ±2.5V
RL= 10kΩ
80
40
Open Loop Gain vs Frequency
135
GAIN (dB)
Closed Loop Gain vs Frequency
60
VS = ±2.5V
SDB–SDCOM
2V/DIV
SUPPLY
CURRENT
2mA/DIV
SUPPLY
CURRENT
2mA/DIV
VIN ,V OUT
500mV/DIV
VIN , VOUT
500mV/DIV
2058 G22
20µs/DIV
ZOUT (Ω)
100
SD–SDCOM
2V/DIV
1
0.1
2058 G23
20µs/DIV
10
0.01
100
A V = +1
A V = +10
A V = +100
1k
10k
100k
FREQUENCY (Hz)
1M
10M
2058 G24
Closed Loop Output Impedance
vs Frequency
Output Impedance in Shutdown
vs Frequency
1k
10G
VS = ±15V
0.01
1
0.1
0.01
100
1k
10k
100k
FREQUENCY (Hz)
10M
1M
10k
1M
100
2058 G25
0.001
–100
0.0001
–120
100k
A V = +1
A V = +10
A V = +100
10M
THD +N (%)
ZOUT (Ω)
10
–80
1k
1
10
100 1k 10k 100k
FREQUENCY (Hz)
1M
10M
0.00001
0.01
AV = +1
AV = –1
0.1
1
OUTPUT AMPLITUDE (VRMS)
10
THD +N (dB)
ZOUT (Ω)
100M
–60
VS = ±15V
RL = 10kΩ
fIN = 1kHz
BW = 80kHz
VS = ±15V
1G
100
THD +N vs Amplitude
0.1
–140
2058 G27
2058 G26
Rev 0
8
For more information www.analog.com
LTC2058
TYPICAL PERFORMANCE CHARACTERISTICS
–120
0.00001
VOUT = 3.5VRMS
VOUT = 2VRMS
10
100
1k
FREQUENCY (Hz)
–140
10k
–120
0.0001
0.00001
100
1k
FREQUENCY (Hz)
7.5
5.0
–140
10k
2058 G28
10.0
0
150°C
SD = SDCOM = VS /2
20
±15V
2.5
1.5
0°C
1.0
–55°C
–40°C
2.0
1.5
10
15
20 25
VS (V)
30
35
2.0
1.5
–55°C
–40°C
25°C
85°C
125°C
150°C
1.0
0.5
1.5 2 2.5 3 3.5
SD – SDCOM (V)
4
0
150
4.5
8
1.5
0
–55°C
–40°C
25°C
85°C
125°C
150°C
0
0.5
1
1.5 2 2.5 3 3.5
SD - SDCOM (V)
4
12 16 20 24 28 32 36 40
VS (V)
VS = ±15V
SDCOM=0V
4
0.5
2058 G34
4
Shutdown Pin Current
vs Shutdown Pin Voltage
5
1.0
5
0
2058 G33
VS = ±15V
SDCOM= 0V
3.0
IS (mA)
IS (mA)
3.5
2.0
1
120
Supply Current vs Shutdown
Control Voltage
2.5
0.5
0
30
60
90
TEMPERATURE (°C)
2058 G32
2.5
0
–30
2058 G31
VS = ±2.5V
SDCOM = –2.5V
3.0
25°C
–40°C
0
–60
40
Supply Current vs Shutdown
Control Voltage
3.5
10
5
SHUTDOWN PIN CURRENT (µA)
5
85°C
–55°C
0.5
0
125°C
15
1.0
0.5
0
150°C
±2.5V
IS (µA)
IS (mA)
IS (mA)
25°C
2.0
10M
25
3.0
2.5
0
100k
1M
FREQUENCY (Hz)
Shutdown Supply Current
vs Supply Voltage
3.5
3.0
10k
2058 G30
Supply Current vs Temperature
3.5
125°C
1k
2058 G29
Supply Current vs Supply Voltage
85°C
VS = ±2.5V
2.5
VOUT = 3.5VRMS
VOUT = 2VRMS
10
OUTPUT AMPLITUDE (VP)
0.0001
–100
0.001
AV = +1
RL = 10kΩ
THD+N < 1%
VS = ±15V
12.5
THD +N (dB)
–100
15.0
VS = ±15V
AV = –1
RI = RF = 10kΩ
BW = 80kHz
–80
0.001
Maximum Undistorted Output
Amplitude vs Frequency
–80
0.01
THD +N (dB)
THD +N (%)
–60
VS = ±15V
AV = +1
RL = 10kΩ
BW = 80kHz
0.01
THD +N vs Frequency
THD +N (%)
0.1
THD +N vs Frequency
4.5
3
2
1
0
–1
–2
ISD –55°C
ISD 125°C
ISDCOM –55°C
ISDCOM 125°C
–3
–4
5
2058 G35
–5
0
0.5
1
1.5 2 2.5 3 3.5
SD – SDCOM (V)
4
4.5
5
2058 G36
Rev 0
For more information www.analog.com
9
LTC2058
TYPICAL PERFORMANCE CHARACTERISTICS
Shutdown Pin Current
vs Supply Voltage
Output Voltage Swing High
vs Load Current
10
SDCOM
1.0
100
VS = ±2.5V
SDB
0.1
–55°C
–40°C
25°C
85°C
125°C
150°C
–0.5
0.01
–1.0
SD = SDCOM = VS/2
0
5
10
15
20 25
VS (V)
30
35
40
0.001
0.001
2058 G37
Output Voltage Swing Low
vs Load Current
100
VS = ±2.5V
–55°C
–40°C
25°C
85°C
125°C
150°C
0.001
0.001
0.01
0.1
1
ISINK (mA)
10
100
VOUT - V- (V)
VOUT – V– (V)
–55°C
–40°C
25°C
85°C
125°C
150°C
0.001
0.001
0.01
2058 G38
0.1
1
ISOURCE (mA)
10
100
2058 G39
Short-Circuit Current
vs Temperature
50
VS = ±15V
45
VS = ±2.5V
40
35
0.01
1
0.1
–55°C
–40°C
25°C
85°C
125°C
150°C
0.01
0.001
0.001
0.01
2058 G40
Short-Circuit Current
vs Temperature
0.1
1
ISINK (mA)
10
100
30
25
20
15
10
SOURCING
SINKING
5
0
–50 –25
2058 G41
0
25 50 75 100 125 150
TEMPERATURE (°C)
2058 G42
Large Signal Response
Large Signal Response
VS = ±15V
VOUT (200mV/DIV)
40
35
ISC (mA)
100
10
0.1
45
10
Output Voltage Swing Low
vs Load Current
1
50
0.1
1
ISOURCE (mA)
0.1
30
25
20
VOUT (2V/DIV)
10
0.01
1
0.01
ISC (mA)
–1.5
–55°C
25°C
150°C
V+ - VOUT (V)
0.5
0
VS = ±15V
10
1
V+ – VOUT
SHUTDOWN PIN CURRENT (µA)
1.5
Output Voltage Swing High
vs Load Current
15
10
5
0
–50 –25
SOURCING
SINKING
0
25 50 75 100 125 150
TEMPERATURE (°C)
VS = ±2.5V
VIN = ±0.5V
AV = +1
CL = 200pF
2µs/DIV
2058 G44
VS = ±15V
VIN = ±5V
AV = +1
CL = 200pF
10µs/DIV
2058 G45
2058 G43
Rev 0
10
For more information www.analog.com
LTC2058
TYPICAL PERFORMANCE CHARACTERISTICS
Small Signal Response
Small Signal Overshoot
vs Capacitive Load
Small Signal Response
100
500ns/DIV
VS = ±2.5V
VIN = ±50mV
AV = +1
CL= 200pF
500ns/DIV
OVERSHOOT (%)
80
2058 G47
VS = ± 15V
AV = +1
OS+
OS–
OS+ R S = 5Ω
OS– R S = 5Ω
70
60
50
40
60
50
40
30
20
0
10p
100p
1n
10n 100n
CLOAD (F)
1µ
10µ 100µ
2058 G48
Large Signal Settling Transient
VS = ±2.5V...±15V
AV= +1
TA= 25°C
VIN
8V/DIV
100
VOUT WITH
AVERAGING
VOUT
–8V
VOUT
0.5mV/DIV
BETTER STABILITY
VS = ±15V
AV = –1
RF = 10kΩ
10
30
20
10µs/DIV
10
0
10p
100p
1n
10n 100n
CLOAD (F)
1µ
10µ 100µ
1
100p
VOUT WITH
AVERAGING
VIN
8V/DIV
1n
10n
100n
1u
CLOAD (F)
10µ
100µ
2058 G50
Large Signal Settling Transient
VOUT WITH
AVERAGING
VIN
8V/DIV
VIN
8V/DIV
10µs/DIV
2058 G52
VS = ±15V
AV = –1
RF = 10kΩ
VOUT WITH
AVERAGING
VOUT
VOUT
0.5mV/DIV
VS = ±15V
AV = –1
RF = 10kΩ CF = 22pF
Large Signal Settling Transient
–8V
–8V
VOUT
2058 G51
< 30% OVERSHOOT
< 10% OVERSHOOT
2058 G49
Large Signal Settling Transient
VOUT
0.5mV/DIV
OS+
OS–
OS+ R S = 5Ω
OS– R S = 5Ω
70
Output Series Resistance vs
CLOAD and Overshoot
1k
VS = ± 2.5V
AV = +1
10
VS = ±15V
VIN = ±50mV
AV = +1
CL= 200pF
RS (Ω)
90
OVERSHOOT (%)
2058 G46
Small Signal Overshoot
vs Capacitive Load
100
80
VOUT (25mV/DIV)
VOUT (25mV/DIV)
90
VOUT
VS = ±15V
AV = –1
RF = 10kΩ C F = 47pF
10µs/DIV
2058 G53
VOUT
0.5mV/DIV
0V
10µs/DIV
2058 G54
Rev 0
For more information www.analog.com
11
LTC2058
TYPICAL PERFORMANCE CHARACTERISTICS
Large Signal Settling Transient
Large Signal Settling Transient
Crosstalk
–80
VOUT
VIN
8V/DIV
VOUT WITH
AVERAGING
0V
VOUT
VOUT
0.5mV/DIV
VS = ±15V
AV = –1
RF= 10kΩ CF=47pF
VS = ±15V
AV = –1
RF = 10kΩ CF = 22pF
10µs/DIV
VOUT
0.5mV/DIV
VOUT WITH
AVERAGING
0V
10µs/DIV
2058 G55
–100
CROSSTALK (dB)
VIN
8V/DIV
VS = ±15V
VOUT = 3.5 VRMS
AV = +1
–90
–110
–120
–130
–140
2058 G56
–150
–160
RL = 100kΩ
RL = 1kΩ
10
100
1k
10k
FREQUENCY (Hz)
100k
2058 G57
EMIRR IN+ vs Frequency
Output Overload Recovery
Output Overload Recovery
140
120
VS = 30V
AV=+1
VIN=–10dBm
VCM= VS/2
VIN
50mV/DIV
VIN
250mV/DIV
EMIRR (dB)
100
80
VOUT
1V/DIV
60
VS = ±2.5V
AV = –100
RF = 10kΩ
CL = 100pF
5µs/DIV
40
20
10M
VOUT
5V/DIV
VS = ±15V
AV = –100
RF = 10kΩ
CL = 100pF
2µs/DIV
2058 G59
2058 G60
EMIRR = 20log(VIN,PEAK/VOUT,DC)
100M
FREQUENCY (Hz)
1G
4G
2058 G58
Input Common Mode Capacitance
vs Input Common Mode Voltage
Output Overload Recovery
Output Overload Recovery
30
VIN
50mV/DIV
VIN
250mV/DIV
25
VOUT
5V/DIV
20
CCM (pF)
V S = ±15V
A V = –100
R F = 10kΩ
C L = 100pF
VS = ±2.5V
A V = –100
R F = 10kΩ
C L = 100pF
VOUT
1V/DIV
VS=5V
VS=30V
15
10
5µs/DIV
2058 G61
2µs/DIV
2058 G62
5
0
0
5
10
15
VCM (V)
20
25
30
2058 G63
Rev 0
12
For more information www.analog.com
LTC2058
PIN FUNCTIONS
S8E
MSE12
OUTA (Pin 1): Amplifier A Output.
SD (Pin 1): Shutdown Control Pin.
–INA (Pin 2): Amplifier A Inverting Input.
V– (Pin 2): Negative Power Supply.
+INA (Pin 3): Amplifier A Noninverting Input.
OUTA (Pin 3): Amplifier A Output.
V– (Pin 4): Negative Power Supply.
GUARD (Pin 4): Guard Ring. No internal connection. (See
Applications Information)
+INB (Pin 5): Amplifier B Noninverting Input.
–INB (Pin 6): Amplifier B Inverting Input.
–INA (Pin 5): Amplifier A Inverting Input.
+INA (Pin 6): Amplifier A Noninverting Input.
OUTB (Pin 7): Amplifier B Output.
+INB (Pin 7): Amplifier B Noninverting Input.
V+ (Pin 8): Positive Power Supply.
Exposed Pad (Pin 9): Must Be Connected to V–.
–INB (Pin 8): Amplifier B Inverting Input.
GUARD/NC (Pin 9): Guard Ring. No internal connection.
(See Application Information)
OUTB (Pin 10): Amplifier B Output.
V+ (Pin 11): Positive Power Supply.
SDCOM (Pin 12): Reference Voltage for SD.
Exposed Pad (Pin 13): Must Be Connected to V–.
Rev 0
For more information www.analog.com
13
LTC2058
BLOCK DIAGRAMS
Amplifier (Each Channel)
V+
250Ω
–IN
V+
V+
–
V–
OUT
V+
+
250Ω
+IN
V–
V–
2058 BD1
V–
Shutdown Circuit (MSE12 Package Only)
V+
V+
0.5µA
10k
SD
–
V+
V–
5.25V
VTH ≈ 1.3V
10k
SDCOM
–+
SD
+
0.75µA
V–
2058 BD2
V–
Rev 0
14
For more information www.analog.com
LTC2058
APPLICATIONS INFORMATION
10
Chopper stabilized amplifiers like the LTC2058 achieve
low offset and 1/f noise by heterodyning DC and flicker
noise to higher frequencies. In a classical chopper stabilized amplifier, this process results in idle tones at the
chopping frequency and its odd harmonics.
The LTC2058 utilizes circuitry to suppress these spurious
artifacts to well below the offset voltage. The typical ripple
magnitude at 100kHz is much less than 1µVRMS.
INPUT-REFERRED
CURRENT NOISE DENSITY (pA/√Hz)
Input Voltage Noise
VS = ±15V
TA=25°C
1
0.1
0.1
The voltage noise spectrum of the LTC2058 is shown in
Figure 1. If lower noise is required, consider the following
circuit from the Typical Applications section: Paralleling
Choppers to Improve Noise.
1
10
100
1k
FREQUENCY (Hz)
10k
100k
2058 F02a
–
1M
+
VS = ±2.5V...±15V
AV=+1
CEXT
TEST CIRCUIT
2058 F02b
Figure 2. Input Current Noise Spectrum
10
chopper and auto-zero amplifiers with switched inputs,
the dominant current noise mechanism is not shot noise.
Input Bias Current
1
10
100 1k 10k 100k 1M 10M
FREQUENCY (Hz)
2058 F01
Figure 1. Input Voltage Noise Spectrum
Input Current Noise
The current noise spectrum of the LTC2058 is shown in
Figure 2. The characteristic curve shows no 1/f behavior.
As with all zero-drift amplifiers, there is a significant current noise component at the offset-nulling frequency. This
phenomenon is discussed in the Input Bias Current section.
It is important to note that the current noise is not equal
to √2qIB A/√Hz. This formula is relevant for base current
in bipolar transistors and diode currents; but for most
100
10
1 TYPICAL UNIT
VS = ±15V
VCM = 0V
1
0.1
LEAKAGE CURRENT
For applications with high source impedances, input current noise can be a significant contributor to total output
noise. For this reason, it is important to consider noise
current interaction with circuit elements placed at the
amplifier’s inputs.
The LTC2058's input bias currents are comprised of two
very different constituents, diode leakage and charge injection. Leakage currents increase with temperature, while the
charge injection from the switching inputs remains relatively constant with temperature. The composite of these
two currents over temperature is illustrated in Figure 3.
INJECTION CURRENT
1
0.1
IB (nA)
INPUT–REFERRED
VOLTAGE NOISE DENSITY (nV/√Hz)
100
CEXT = 0pF
CEXT = 22pF
25°C MAX IB SPEC
0.01
–50 –25
0
25 50 75 100 125 150
TEMPERATURE (°C)
2058 F03
Figure 3. Input Bias Current vs Temperature
For more information www.analog.com
Rev 0
15
LTC2058
APPLICATIONS INFORMATION
How the various input bias currents behave and contribute
to error depends on the nature of the source impedance.
For the input bias currents specified in the electrical tables,
the source impedances are high value resistors bypassed
with shunt filter capacitance. Figure 4 shows the effective DC error as an input referred current error (output
DC voltage error divided by gain and then by the source
resistance) as a function of the filter capacitance. Note
that the effective DC error decreases as the capacitance
increases. The added external capacitance (CEXT) also
reduces the input current noise as shown in Figure 2.
Another function of the input capacitance is to reduce
the effects of charge injection. The charge injection based
current has a frequency component at the chopping frequency and its harmonics. In time domain these frequency
components appear as current pulses (appearing at regular
intervals related to the chopping frequency). When these
small current pulses interact with source impedances or
gain setting resistors, the resulting voltage spikes are
amplified by the closed loop gain. For higher source impedances, this may cause the 100kHz chopping frequency to
be visible in the output spectrum, which is a phenomenon
known as clock feedthrough. To prevent excessive clock
VS = ±15V
Above 50°C, leakage of the ESD protection diodes begins to
dominate the input bias current and continues to increase
exponentially at elevated temperatures. Unlike injection
current, leakage currents are in the same direction for both
inputs. Therefore, the output error due to leakage currents
can be mitigated by matching the source impedances
seen by the two inputs. Keep in mind that if the sourceimpedance-matching technique is employed to cancel
the effect of the leakage currents, below 50°C there is an
offset voltage error of 2IB x R due to the charge-injection
currents. If IB = 100pA and R = 10k, the error is 2µV.
In order to achieve accuracy on the microvolt level, thermocouple effects must be considered. Any connection
of dissimilar metals forms a thermoelectric junction and
generates a small temperature-dependent voltage. Also
known as the Seebeck Effect, these thermal EMFs can be
the dominant error source in low drift circuits.
150
EFFECTIVE IB (pA)
Injection currents from the two inputs are of equal magnitude but opposite direction. Therefore, input bias current
effects on offset voltage due to injection currents will not
be canceled by placing matched impedances at both inputs.
Thermocouple Effects
200
100
50
0
feedthrough, keep gain-setting resistors and source impedances as low as possible. When DC highly resistive
source impedance is required, the capacitor across the
source impedance reduces the AC impedance, reducing
the amplitude of the input voltage spikes. Another way to
reduce clock injection effects is to bandwidth limit after
the op amp output.
0
50
1M
100
CEXT (pF)
150
200
2058 F04a
–
+
CEXT
Connectors, switches, relay contacts, sockets, resistors,
and solder are all candidates for significant thermal EMF
generation. Even junctions of copper wire from different
manufacturers can generate thermal EMFs of 200nV/°C,
which is 8 times the maximum drift specification of the
LTC2058. Figure 5 and Figure 6 illustrate the potential
magnitude of these voltages and their sensitivity to temperature.
TEST CIRCUIT
2058 F04b
Figure 4. Input Bias Current vs Input Capacitance
Rev 0
16
For more information www.analog.com
LTC2058
MICROVOLTS REFERRED TO 25°C
APPLICATIONS INFORMATION
3.0
2.8
2.6
2.4
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.800
0.600
0.400
0.200
0
25
35
30
40
In order to minimize thermocouple-induced errors, attention must be given to circuit board layout and component
selection. It is good practice to minimize the number of
junctions in the amplifier’s input signal path and avoid connectors, sockets, switches, and relays whenever possible.
If such components are required, they should be selected
for low thermal EMF characteristics. Furthermore, the
number, type, and layout of junctions should be matched
for both inputs with respect to thermal gradients on the
circuit board. Doing so may involve deliberately introducing
dummy junctions to offset unavoidable junctions.
45
TEMPERATURE (°C)
Air currents can also lead to thermal gradients and cause
significant noise in measurement systems. It is important
to prevent airflow across sensitive circuits. Doing so will
often reduce thermocouple noise substantially.
2058 F05
THERMALLY PRODUCED VOLTAGE IN MICROVOLTS
Figure 5. Thermal EMF Generated by Two Copper
Wires from Different Manufactures
A summary of techniques can be found in Figure 7.
100
SLOPE ≈ 1.5µV/°C
BELOW 25°C
50
Leakage Effects
64% SN/36% Pb
0
Leakage currents into high impedance signal nodes can
easily degrade measurement accuracy of sub-nanoamp
signals. High voltage and high temperature applications
are especially susceptible to these issues. Quality insulation materials should be used, and insulating surfaces
should be cleaned to remove fluxes and other residues.
For humid environments, surface coating may be necessary to provide a moisture barrier.
60% Cd/40% SN
SLOPE ≈ 160nV/°C
BELOW 25°C
–50
–100
10
30
0
40
50
20
SOLDER-COPPER JUNCTION DIFFERENTIAL TEMPERATURE
SOURCE: NEW ELECTRONICS 02-06-77
2058 F06
Figure 6. Solder-Copper Thermal EMFs
#
HEAT SOURCE/
POWER DISSIPATOR
RELAY
**
VTHERMAL
–+
THERMAL
GRADIENT
VTHERMAL
VIN
*
–+
RG
RF §
–IN
†
** RG
‡
LTC2058
RL§
+IN
RF
MATCHING RELAY
NC
* CUT SLOTS IN PCB FOR THERMAL ISOLATION.
** INTRODUCE DUMMY JUNCTIONS AND COMPONENTS TO OFFSET UNAVOIDABLE JUNCTIONS OR CANCEL THERMAL EMFs.
† ALIGN INPUTS SYMMETRICALLY WITH RESPECT TO THERMAL GRADIENTS.
‡ INTRODUCE DUMMY TRACES AND COMPONENTS FOR SYMMETRICAL THERMAL HEAT SINKING.
§ LOADS AND FEEDBACK CAN DISSIPATE POWER AND GENERATE THERMAL GRADIENTS. BE AWARE OF THEIR THERMAL EFFECTS.
# COVER CIRCUIT TO PREVENT AIR CURRENTS FROM CREATING THERMAL GRADIENTS.
2057 F07
Figure 7. Techniques for Minimizing Thermocouple-Induced Errors
Rev 0
For more information www.analog.com
17
LTC2058
APPLICATIONS INFORMATION
Board leakage can be minimized by encircling the input
connections with a guard ring operated at a potential very
close to that of the inputs. The ring must be tied to a low
impedance node. For inverting configurations, the guard
ring should be tied to the potential of the positive input
(+IN). For noninverting configurations, the guard ring
should be tied to the potential of the negative input (–IN).
In order for this technique to be effective, the guard ring
must not be covered by solder mask. Ringing both sides
of the printed circuit board may be required. See Figure
8a and Figure 8b for examples of proper layout.
RF**
SD
SDCOM
V–
V+
OUTA
RG
OUTB
V–
GRD
GRD
–INA
–INB
+INA
*
+INB
§
LEAKAGE CURRENT
HIGH- Z
SENSOR
GUARD RING
(NO SOLDER MASK
OVER GUARD RING)
ALL RESISTORS 0603
* MINIMIZE SPACING TO MAXIMIZE THE CLEARANCE BETWEEN
THE EXPOSED GUARD RING AND THE EXPOSED PAD
** VERROR = ILEAK RG; RG
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