LINER LT1813CS8 Dual 3ma, 100mhz, 750v/us operational amplifier Datasheet

LT1813
Dual 3mA, 100MHz, 750V/µs
Operational Amplifier
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FEATURES
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DESCRIPTIO
The LT®1813 is a low power, high speed, very high slew
rate operational amplifier with excellent DC performance.
The LT1813 features reduced supply current, lower input
offset voltage, lower input bias current and higher DC gain
than other devices with comparable bandwidth. The circuit
topology is a voltage feedback amplifier with the slewing
characteristics of a current feedback amplifier.
100MHz Gain Bandwidth
750V/µs Slew Rate
3.6mA Maximum Supply Current per Amplifier
8nV/√Hz Input Noise Voltage
Unity-Gain Stable
1.5mV Maximum Input Offset Voltage
4µA Maximum Input Bias Current
400nA Maximum Input Offset Current
40mA Minimum Output Current, VOUT = ±3V
±3.5V Minimum Input CMR, VS = ±5V
Specified at ±5V, Single 5V
Available in MS8 and SO-8 Packages
The output drives a 100Ω load to ±3.5V with ±5V supplies.
On a single 5V supply, the output swings from 1.1V to 3.9V
with a 100Ω load connected to 2.5V. The amplifier is stable
with a 1000pF capacitive load which makes it useful in
buffer and cable driver applications.
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APPLICATIO S
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Wideband Amplifiers
Buffers
Active Filters
Video and RF Amplification
Cable Drivers
Data Acquisition Systems
, LTC and LT are registered trademarks of Linear Technology Corporation.
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The LT1813 is manufactured on Linear Technology’s
advanced low voltage complementary bipolar process.
For higher supply voltage single, dual and quad operational amplifiers with up to 70MHz gain bandwidth, see the
LT1351 through LT1365 data sheets.
TYPICAL APPLICATIO
4MHz, 4th Order Butterworth Filter
Filter Frequency Response
10
232Ω
0
274Ω
665Ω
VIN
–
47pF
274Ω
220pF
562Ω
1/2 LT1813
+
470pF
–
22pF
1/2 LT1813
+
VOUT
1813 TA01
VOLTAGE GAIN (dB)
232Ω
–10
–20
–30
–40
–50
–60
–70
–80
–90
0.1
VS = ±5V
VIN = 600mVP-P
PEAKING < 0.12dB
1
10
FREQUENCY (MHz)
100
1813 TA02
1
LT1813
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ABSOLUTE MAXIMUM RATINGS (Note 1)
Total Supply Voltage (V + to V –) ............................. 12.6V
Differential Input Voltage (Transient Only, Note 2) ... ±3V
Input Voltage ........................................................... ±VS
Output Short-Circuit Duration (Note 3) ............ Indefinite
Operating Temperature Range ................ – 40°C to 85°C
Specified Temperature Range
(Notes 8, 9) ......................................... – 40°C to 85°C
Maximum Junction Temperature ......................... 150°C
Storage Temperature Range .................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................... 300°C
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PACKAGE/ORDER INFORMATION
ORDER PART
NUMBER
TOP VIEW
OUT A
–IN A
+IN A
V–
1
2
3
4
8
7
6
5
V+
OUT B
–IN B
+IN B
MS8 PACKAGE
8-LEAD PLASTIC MSOP
LT1813DMS8*
ORDER PART
NUMBER
TOP VIEW
OUT A 1
8
V+
–IN A 2
7
OUT B
6
–IN B
5
+IN B
LT1813CS8
LT1813IS8
LT1813DS8*
A
+IN A 3
V– 4
MS8 PART MARKING
TJMAX = 150°C, θJA = 250°C/ W
LTGZ
B
S8 PART MARKING
S8 PACKAGE
8-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 150°C/ W
1813
1813I
1813D
Consult factory for Military grade parts. *See note 9.
ELECTRICAL CHARACTERISTICS
TA = 25°C, VS = ±5V, VCM = 0V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
VOS
Input Offset Voltage
(Note 4)
IOS
Input Offset Current
IB
Input Bias Current
en
Input Noise Voltage
f = 10kHz
in
Input Noise Current
f = 10kHz
RIN
Input Resistance
VCM = ±3.5V
Differential
CIN
Input Capacitance
Input Voltage Range (High)
Input Voltage Range (Low)
CMRR
Common Mode Rejection Ratio
MIN
3
3.5
VCM = ±3.5V
75
TYP
MAX
UNITS
0.5
1.5
mV
50
400
nA
– 0.9
±4
µA
8
nV/√Hz
1
pA/√Hz
10
1.5
MΩ
MΩ
2
pF
4.2
– 4.2
85
– 3.5
V
V
dB
PSRR
Power Supply Rejection Ratio
VS = ±2V to ±5.5V
78
96
dB
AVOL
Large-Signal Voltage Gain
VOUT = ±3V, RL = 500Ω
VOUT = ±3V, RL = 100Ω
1.5
1.0
3.0
2.5
V/mV
V/mV
VOUT
Output Swing
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
±3.80
±3.35
±4.0
±3.5
V
V
IOUT
Output Current
VOUT = ±3V, 30mV Overdrive
±40
±60
mA
ISC
Short-Circuit Current
VOUT = 0V, VIN = ±1V
±75
±100
mA
SR
Slew Rate
AV = – 1 (Note 5)
500
750
V/µs
Full Power Bandwidth
3V Peak (Note 6)
40
MHz
2
LT1813
ELECTRICAL CHARACTERISTICS
TA = 25°C, VS = ±5V, VCM = 0V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
GBW
tr, tf
Gain Bandwidth
Rise Time, Fall Time
Overshoot
Propagation Delay
Output Resistance
Channel Separation
Supply Current
f = 200kHz
AV = 1, 10% to 90%, 0.1V, RL = 100Ω
AV = 1, 0.1V, RL = 100Ω
50% VIN to 50% VOUT, 0.1V, RL = 100Ω
AV = 1, f = 1MHz
VOUT = ±3V, RL = 100Ω
Per Amplifier
RO
IS
MIN
TYP
75
100
2
25
2.8
0.4
90
3
82
MAX
UNITS
3.6
MHz
ns
%
ns
Ω
dB
mA
TA = 25°C, VS = 5V, VCM = 2.5V, RL to 2.5V unless otherwise noted.
SYMBOL
VOS
IOS
IB
en
in
RIN
PARAMETER
Input Offset Voltage
Input Offset Current
Input Bias Current
Input Noise Voltage
Input Noise Current
Input Resistance
CIN
CMRR
AVOL
Input Capacitance
Input Voltage Range (High)
Input Voltage Range (Low)
Common Mode Rejection Ratio
Large-Signal Voltage Gain
VOUT
Output Swing (High)
Output Swing (Low)
IOUT
ISC
SR
GBW
tr, tf
RO
IS
Output Current
Short-Circuit Current
Slew Rate
Full Power Bandwidth
Gain Bandwidth
Rise Time, Fall Time
Overshoot
Propagation Delay
Output Resistance
Channel Separation
Supply Current
CONDITIONS
(Note 4)
MIN
f = 10kHz
f = 10kHz
VCM = 1.5V to 3.5V
Differential
3
3.5
VCM = 1.5V to 3.5V
VOUT = 1.5V to 3.5V, RL = 500Ω
VOUT = 1.5V to 3.5V, RL = 100Ω
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
VOUT = 3.5V or 1.5V, 30mV Overdrive
VOUT = 2.5V, VIN = ±1V
AV = – 1 (Note 5)
1V Peak (Note 6)
f = 200kHz
AV = 1, 10% to 90%, 0.1V, RL = 100Ω
AV = 1, 0.1V, RL = 100Ω
50% VIN to 50% VOUT, 0.1V, RL = 100Ω
AV = 1, f = 1MHz
VOUT = 1.5V to 3.5V, RL = 100Ω
Per Amplifier
73
1.0
0.7
3.9
3.7
±25
±55
200
65
81
TYP
0.7
50
–1
8
1
20
1.5
2
4
1
82
2.0
1.5
4.1
3.9
0.9
1.1
±35
±75
350
55
94
2.1
25
3
0.45
92
2.9
MAX
2
400
±4
1.5
1.1
1.3
3.6
UNITS
mV
nA
µA
nV/√Hz
pA/√Hz
MΩ
MΩ
pF
V
V
dB
V/mV
V/mV
V
V
V
V
mA
mA
V/µs
MHz
MHz
ns
%
ns
Ω
dB
mA
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range
0°C ≤ TA ≤ 70°C. VS = ±5V, VCM = 0V unless otherwise noted (Note 9).
SYMBOL
VOS
IOS
IB
PARAMETER
Input Offset Voltage
Input VOS Drift
Input Offset Current
Input Bias Current
CONDITIONS
(Note 4)
(Note 7)
MIN
TYP
●
●
●
●
10
MAX
2
15
500
±5
UNITS
mV
µV/°C
nA
µA
3
LT1813
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range
0°C ≤ TA ≤ 70°C. VS = ±5V, VCM = 0V unless otherwise noted (Note 9).
SYMBOL
CMRR
PSRR
AVOL
PARAMETER
Input Voltage Range (High)
Input Voltage Range (Low)
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Large-Signal Voltage Gain
VOUT
Output Swing
IOUT
ISC
SR
GBW
Output Current
Short-Circuit Current
Slew Rate
Gain Bandwidth
Channel Separation
Supply Current
IS
CONDITIONS
●
●
VCM = ±3.5V
VS = ±2V to ±5.5V
VOUT = ±3V, RL = 500Ω
VOUT = ±3V, RL = 100Ω
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
VOUT = ±3V, 30mV Overdrive
VOUT = 0V, VIN = ±1V
AV = – 1 (Note 5)
f = 200kHz
VOUT, ±3V, RL = 100Ω
Per Amplifier
●
●
●
●
●
●
●
●
●
●
●
MIN
3.5
TYP
MAX
– 3.5
73
76
1.0
0.7
±3.70
±3.25
±35
±60
400
65
81
●
4.5
●
2.5
15
500
±5
UNITS
V
V
dB
dB
V/mV
V/mV
V
V
mA
mA
V/µs
MHz
dB
mA
0°C ≤ TA ≤ 70°C, VS = 5V, VCM = 2.5V, RL to 2.5V unless otherwise noted (Note 9).
VOS
CMRR
AVOL
Input Offset Voltage
Input VOS Drift
Input Offset Current
Input Bias Current
Input Voltage Range (High)
Input Voltage Range (Low)
Common Mode Rejection Ratio
Large-Signal Voltage Gain
VOUT
Output Swing (High)
IOS
IB
Output Swing (Low)
IOUT
ISC
SR
GBW
IS
Output Current
Short-Circuit Current
Slew Rate
Gain Bandwidth
Channel Separation
Supply Current
(Note 4)
(Note 7)
4.5
mV
µV/°C
nA
µA
V
V
dB
V/mV
V/mV
V
V
V
V
mA
mA
V/µs
MHz
dB
mA
TYP
MAX
UNITS
3
mV
10
30
µV/°C
600
nA
±6
µA
– 3.5
V
V
10
●
●
●
VCM = 1.5V to 3.5V
VOUT = 1.5V to 3.5V, RL = 500Ω
VOUT = 1.5V to 3.5V, RL = 100Ω
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
VOUT = 3.5V or 1.5V, 30mV Overdrive
VOUT = 2.5V, VIN = ±1V
AV = – 1 (Note 5)
f = 200kHz
VOUT, 1.5V to 3.5V, RL = 100Ω
Per Amplifier
●
●
3.5
●
71
0.7
0.5
3.8
3.6
●
●
●
●
1.5
1.2
1.4
●
●
●
●
●
●
●
±20
±45
150
55
80
●
– 40°C ≤ TA ≤ 85°C. VS = ±5V, VCM = 0V unless otherwise noted (Notes 8, 9).
SYMBOL
PARAMETER
CONDITIONS
MIN
VOS
Input Offset Voltage
(Note 4)
●
Input VOS Drift
(Note 7)
●
IOS
Input Offset Current
●
IB
Input Bias Current
●
Input Voltage Range (High)
Input Voltage Range (Low)
●
●
3.5
CMRR
Common Mode Rejection Ratio
VCM = ±3.5V
●
72
dB
PSRR
Power Supply Rejection Ratio
VS = ±2V to ±5.5V
●
75
dB
4
LT1813
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the temperature range
– 40°C ≤ TA ≤ 85°C. VS = ±5V, VCM = 0V unless otherwise noted (Notes 8, 9).
SYMBOL
PARAMETER
CONDITIONS
AVOL
Large-Signal Voltage Gain
VOUT = ±3V, RL = 500Ω
VOUT = ±3V, RL = 100Ω
●
●
0.8
0.6
VOUT
Output Swing
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
●
●
±3.60
±3.15
IOUT
Output Current
VOUT = ±3V, 30mV Overdrive
●
±30
mA
ISC
Short-Circuit Current
VOUT = 0V, VIN = ±1V
●
±55
mA
SR
Slew Rate
AV = – 1 (Note 5)
●
350
V/µs
GBW
Gain Bandwidth
f = 200kHz
●
60
MHz
Channel Separation
VOUT, ±3V, RL = 100Ω
●
80
dB
Supply Current
Per Amplifier
●
5
mA
3.5
mV
IS
MIN
TYP
MAX
UNITS
V/mV
V/mV
V
V
– 40°C ≤ TA ≤ 85°C, VS = 5V, VCM = 2.5V, RL to 2.5V unless otherwise noted (Notes 8, 9).
VOS
Input Offset Voltage
(Note 4)
●
Input VOS Drift
(Note 7)
●
30
µV/°C
IOS
Input Offset Current
●
600
nA
IB
Input Bias Current
●
±6
µA
Input Voltage Range (High)
Input Voltage Range (Low)
●
●
3.5
1.5
V
V
10
CMRR
Common Mode Rejection Ratio
VCM = 1.5V to 3.5V
●
70
dB
AVOL
Large-Signal Voltage Gain
VOUT = 1.5V to 3.5V, RL = 500Ω
VOUT = 1.5V to 3.5V, RL = 100Ω
●
●
0.6
0.4
V/mV
V/mV
VOUT
Output Swing (High)
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
●
●
3.7
3.5
V
V
Output Swing (Low)
RL = 500Ω, 30mV Overdrive
RL = 100Ω, 30mV Overdrive
●
●
Output Current
VOUT = 3.5V or 1.5V, 30mV Overdrive
●
±17
IOUT
1.3
1.5
V
V
mA
ISC
Short-Circuit Current
VOUT = 2.5V, VIN = ±1V
●
±40
mA
SR
Slew Rate
AV = – 1 (Note 5)
●
125
V/µs
GBW
Gain Bandwidth
f = 200kHz
●
50
MHz
Channel Separation
VOUT, 1.5V to 3.5V, RL = 100Ω
●
79
Supply Current
Per Amplifier
●
IS
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: Differential inputs of ±3V are appropriate for transient operation
only, such as during slewing. Large sustained differential inputs can cause
excessive power dissipation and may damage the part.
Note 3: A heat sink may be required to keep the junction temperature
below absolute maximum when the output is shorted indefinitely.
Note 4: Input offset voltage is pulse tested and is exclusive of warm-up
drift.
Note 5: Slew rate is measured between ±2V on the output with ±3V input
for ±5V supplies and 2VP-P on the output with a 3VP-P input for single 5V
supplies.
dB
5
mA
Note 6: Full power bandwidth is calculated from the slew rate:
FPBW = SR/2πVP.
Note 7: This parameter is not 100% tested.
Note 8: The LT1813C is guaranteed to meet specified performance from
0°C to 70°C and is designed, characterized and expected to meet these
extended temperature limits, but is not tested at – 40°C and 85°C. The
LT1813I is guaranteed to meet the extended temperature limits.
Note 9: The LT1813D is 100% production tested at 25°C. It is designed,
characterized and expected to meet the 0°C to 70°C specifications
although it is not tested or QA sampled at these temperatures. The
LT1813D is guaranteed functional from –40°C to 85°C but may not meet
those specifications.
5
LT1813
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TYPICAL PERFOR A CE CHARACTERISTICS
Input Common Mode Range
vs Supply Voltage
Supply Current vs Temperature
V+
5
PER AMPLIFIER
VS = ± 2.5V
2
1
–1.0
INPUT BIAS CURRENT (µA)
INPUT COMMON MODE RANGE (V)
VS = ± 5V
3
0
– 0.5
4
SUPPLY CURRENT (mA)
Input Bias Current
vs Common Mode Voltage
–1.5
– 2.0
TA = 25°C
∆VOS < 1mV
2.0
1.5
1.0
TA = 25°C
VS = ± 5V
– 0.5
–1.0
–1.5
0.5
50
25
0
75
TEMPERATURE (°C)
100
V–
125
0
1
4
3
2
5
SUPPLY VOLTAGE (± V)
1813 G01
INPUT VOLTAGE NOISE (nV/√Hz)
– 0.9
–1.0
–1.1
in
10
1
en
1
50
25
75
0
TEMPERATURE (°C)
100
10
125
100
1k
10k
FREQUENCY (Hz)
TA = 25°C
– 0.5 VIN = 30mV
OUTPUT VOLTAGE SWING (V)
OPEN-LOOP GAIN (dB)
67.5
RL = 500Ω
RL = 100Ω
65.0
62.5
50
25
75
0
TEMPERATURE (°C)
100
125
1813 G07
6
VS = ± 5V
67.5
VS = ± 2.5V
65.0
62.5
0.1
100k
60
100
1k
LOAD RESISTANCE (Ω)
Output Voltage Swing
vs Load Current
V+
– 0.5
RL = 500Ω
RL = 100Ω
– 2.0
2.0
RL = 100Ω
1.5
1.0
RL = 500Ω
1
4
3
2
5
SUPPLY VOLTAGE (± V)
–1.0
–1.5
VS = ± 5V
VIN = 30mV
85°C
25°C
– 40°C
– 2.0
2.0
1.5
1.0
0.5
V–
0
10k
1813 G06
–1.0
–1.5
0.5
60.0
–50 –25
70.0
V+
VS = ± 5V
VO = ± 3V
70.0
72.5
Output Voltage Swing
vs Supply Voltage
Open-Loop Gain vs Temperature
72.5
TA = 25°C
1813 G05
1813 G04
75.0
75.0
OUTPUT VOLTAGE SWING (V)
INPUT BIAS CURRENT (µA)
10
TA = 25°C
VS = ± 5V
AV = 101
RS = 10k
INPUT CURRENT NOISE (pA/√Hz)
– 0.8
–1.2
– 50 – 25
Open-Loop Gain
vs Resistive Load
100
VS = ± 5V
5.0
1813 G03
Input Noise Spectral Density
– 0.7
0
2.5
– 2.5
INPUT COMMON MODE VOLTAGE (V)
1813 G02
Input Bias Current
vs Temperature
– 0.6
– 2.0
– 5.0
7
6
OPEN-LOOP GAIN (dB)
0
–50 –25
6
7
1813 G02
V–
–60
–40
0
20
40
–20
OUTPUT CURRENT (mA)
60
1813 G09
LT1813
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TYPICAL PERFOR A CE CHARACTERISTICS
Output Short-Circuit Current
vs Temperature
Settling Time vs Output Step
VS = ± 5V
100
4
SOURCE
3
100
SINK
90
2
1
0
–1
VS = ± 5V
AV = –1
RF = 500Ω
CF = 3pF
0.1% SETTLING
–2
–3
–4
–5
100
125
0
5
20
15
10
25
SETTLING TIME (ns)
0
–20
±2.5V
±2.5V
±5V
40
±5V
20
20
10
0
0
CROSSTALK (dB)
60
30
100k
1M
10M
FREQUENCY (Hz)
100M
–30
–40
–50
–60
1M
10M
100M
FREQUENCY (Hz)
–2
–50 –25
VS = ±2.5V
–6
–8
–10
40
50
25
0
75
TEMPERATURE (°C)
4
2
VS = ±2.5V
38
125
100
Frequency Response
vs Capacitive Load, AV = – 1
TA = 25°C
AV = 2
RL = 100Ω
6
VS = ±5V
42
1813 G15
12
8
–4
VS = ±5V
0
–2
TA = 25°C
AV = –1
V = ±5V
8 S
RF = RG = 500Ω
NO RL
CL= 1000pF
CL= 500pF
CL= 200pF
4
CL= 100pF
CL= 50pF
CL= 0
0
–4
–4
–12
–14
1M
1000M
Frequency Response
vs Supply Voltage, AV = 2
VOLTAGE MAGNITUDE (dB)
VOLTAGE MAGNITUDE (dB)
0
PHASE MARGIN
VS = ±5V
1813 G14
6
2
GBW
VS = ±2.5V
85
PHASE MARGIN
VS = ±2.5V
–90
100k
–40
1000M
Frequency Response
vs Supply Voltage, AV = 1
TA = 25°C
AV = 1
NO RL
95
–80
1813 G13
4
GBW
VS = ± 5V
105
–70
–20
–10
10k
100M
PHASE MARGIN (DEG)
80
40
1M
10M
FREQUENCY (Hz)
115
TA = 25°C
AV = 10
VIN = 0dBm
RL = 100Ω
–10
100
PHASE (DEG)
GAIN (dB)
120
PHASE
GAIN
100k
Gain Bandwidth and Phase
Margin vs Temperature
Crosstalk vs Frequency
50
TA = 25°C
VS = ± 5V
1813 G12
GAIN BANDWIDTH (MHz)
60
0.1
1813 G11
Gain and Phase vs Frequency
TA = 25°C
AV = –1
RF = RG = 500Ω
AV = 1
1
0.001
10k
35
30
1813 G10
70
AV = 10
0.01
VOLTAGE MAGNITUDE (dB)
75
0
25
50
TEMPERATURE (°C)
AV = 100
10
OUTPUT IMPEDANCE (Ω)
110
80
–50 –25
Output Impedance vs Frequency
5
OUTPUT STEP (V)
OUTPUT SHORT-CIRCUIT CURRENT (mA)
120
10M
100M
FREQUENCY (Hz)
500M
1813 G16
–6
1M
–8
10M
100M
FREQUENCY (Hz)
500M
1813 G17
1
10M
FREQUENCY (Hz)
100M 200M
1813 G18
7
LT1813
U W
TYPICAL PERFOR A CE CHARACTERISTICS
105
GBW
RL = 100Ω
90
85
44
PHASE MARGIN
RL = 100Ω
80
42
POWER SUPPLY REJECTION RATIO (dB)
95
PHASE MARGIN (DEG)
GBW
RL = 500Ω
40
PHASE MARGIN
RL = 500Ω
1
4
3
5
2
SUPPLY VOLTAGE (±V)
6
TA = 25°C
AV = 1
VS = ±5V
80
–PSRR
+PSRR
60
40
20
7
Slew Rate vs Supply Voltage
10k
1M
100k
FREQUENCY (Hz)
10M
20
1k
100M
400
300
TA =25°C
AV = –1
V = ±5V
1000 RS = R = R = 500Ω
F
G
L
350
SR +
SR –
300
250
200
100M
Slew Rate vs Input Level
SLEW RATE (V/µs)
SR –
500
10M
1200
TA =25°C
AV = –1
V = ±1V
400 RIN= R = R = 500Ω
F
G
L
+
600
1M
100k
FREQUENCY (Hz)
10k
1813 G21
Slew Rate vs Supply Voltage
450
SLEW RATE (V/µs)
SLEW RATE (V/µs)
40
1813 G20
1000
SR
60
0
1k
1813 G19
TA =25°C
900 AV = –1
/2
V =V
800 RIN= R S(TOTAL)
F
G = RL = 500Ω
700
TA = 25°C
VS = ±5V
80
0
38
0
Common Mode Rejection Ratio
vs Frequency
100
100
TA = 25°C
100
GAIN BANDWIDTH (MHz)
Power Supply Rejection Ratio
vs Frequency
COMMON MODE REJECTION RATIO (dB)
Gain Bandwidth and Phase
Margin vs Supply Voltage
SR +
800
SR –
600
400
100
200
0
1
4
3
2
5
SUPPLY VOLTAGE (±V)
200
7
6
0
1
4
3
2
5
SUPPLY VOLTAGE (±V)
SLEW RATE (V/µs)
800
TOTAL HARMONIC DISTORTION + NOISE (%)
1100
900
SR –
VS = ± 5V
700
600
500
400
300
200
–50
SR – VS = ±2.5V
SR + VS = ±2.5V
–25
0
75
50
25
TEMPERATURE (°C)
100
125
1813 G25
8
0
1
2
4
3
5
6
INPUT LEVEL (VP-P)
9
AV = – 1
8
AV = –1
0.005
AV = 1
0.002
TA = 25°C
VS = ± 5V
VO = 2VP-P
RL = 500Ω
10
8
Undistorted Output Swing
vs Frequency
0.01
0.001
7
1813 G24
Total Harmonic Distortion + Noise
vs Frequency
Slew Rate vs Temperature
1000
7
1813 G23
1813 G22
SR +
VS = ± 5V
6
OUTPUT VOLTAGE (VP-P)
0
100
6
5
4
3
2
1
1k
10k
FREQUENCY (Hz)
100k
1813 G26
AV = 1
7
VS = ± 5V
RL = 100Ω
2% MAX DISTORTION
0
100k
1M
10M
FREQUENCY (Hz)
100M
1813 G27
LT1813
U W
TYPICAL PERFOR A CE CHARACTERISTICS
AV = 2
VS = ± 5V
VO = 2VP-P
–50
2ND HARMONIC
3RD HARMONIC
RL = 100Ω
–60
–70
–80
3RD HARMONIC
–90
2ND HARMONIC
RL = 500Ω
–100
100k
100
DIFFERENTIAL GAIN
RL = 150Ω
0.4
90
0.3
80
DIFFERENTIAL GAIN
RL = 1k
0.2
0.1
0.5
0
DIFFERENTIAL PHASE
RL = 150Ω
0.4
0.3
0.2
10M
1813 G28
Small-Signal Transient (AV = 1)
1813 G31
Large-Signal Transient (AV = 1)
1813 G34
AV = 1
70
60
50
AV = –1
40
30
10
0
0
1M
FREQUENCY (Hz)
TA = 25°C
VS = ±5V
20
DIFFERENTIAL PHASE
RL = 1k
0.1
DIFFERENTIAL GAIN (%)
HARMONIC DISTORTION (dB)
–40
Capacitive Load Handling
0.5
OVERSHOOT (%)
–30
Differential Gain and Phase
vs Supply Voltage
DIFFERENTIAL PHASE (DEG)
2nd and 3rd Harmonic Distortion
vs Frequency
4
10
8
6
TOTAL SUPPLY VOLTAGE (V)
12
10
100
1000
CAPACITIVE LOAD (pF)
10000
1813 G30
1813 G29
Small-Signal Transient (AV = –1)
Small-Signal Transient
(AV = 1, CL = 100pF)
1813 G32
Large-Signal Transient (AV = –1)
1813 G35
1813 G33
Large-Signal Transient
(AV = –1, CL = 200pF)
1813 G36
9
LT1813
U
W
U
U
APPLICATIONS INFORMATION
Layout and Passive Components
Capacitive Loading
The LT1813 amplifier is more tolerant of less than ideal
layouts than other high speed amplifiers. For maximum
performance (for example, fast settling) use a ground
plane, short lead lengths and RF-quality bypass capacitors
(0.01µF to 0.1µF). For high drive current applications, use
low ESR bypass capacitors (1µF to 10µF tantalum).
The LT1813 is stable with a 1000pF capacitive load which
is outstanding for a 100MHz amplifier. This is accomplished by sensing the load induced output pole and
adding compensation at the amplifier gain node. As the
capacitive load increases, both the bandwidth and phase
margin decrease so there will be peaking in the frequency
domain and in the transient response. Coaxial cable can be
driven directly, but for best pulse fidelity, a resistor of
value equal to the characteristic impedance of the cable
(i.e., 75Ω) should be placed in series with the output. The
other end of the cable should be terminated with the same
value resistor to ground.
The parallel combination of the feedback resistor and gain
setting resistor on the inverting input combine with the
input capacitance to form a pole that can cause peaking or
oscillations. If feedback resistors greater than 2k are used,
a parallel capacitor of value
CF > RG • CIN/RF
should be used to cancel the input pole and optimize
dynamic performance. For applications where the DC
noise gain is 1 and a large feedback resistor is used, CF
should be greater than or equal to CIN. An example would
be an I-to-V converter.
Input Considerations
Each of the LT1813 amplifier inputs is the base of an NPN
and PNP transistor whose base currents are of opposite
polarity and provide first-order bias current cancellation.
Because of variation in the matching of NPN and PNP beta,
the polarity of the input current can be positive or negative.
The offset current does not depend on beta matching and
is well controlled. The use of balanced source resistance
at each input is recommended for applications where DC
accuracy must be maximized. The inputs can withstand
differential input voltages of up to 3V without damage and
need no clamping or source resistance for protection.
Differential inputs generate the large supply currents (up
to 40mA) required for high slew rates. Typically, power
dissipation does not significantly increase in normal,
closed-loop operation because of the low duty cycle of the
transient inputs.
The device should not be used as a comparator because
with sustained differential inputs, excessive power dissipation may result.
10
Slew Rate
The slew rate is proportional to the differential input
voltage. Highest slew rates are therefore seen in the
lowest gain configurations. For example, a 5V output step
in a gain of 10 has a 0.5V input step, whereas in unity gain
there is a 5V input step. The LT1813 is tested for slew rate
in a gain of – 1. Lower slew rates occur in higher gain
configurations.
Power Dissipation
The LT1813 combines high speed and large output drive
in a small package. It is possible to exceed the maximum
junction temperature under certain conditions. Maximum
junction temperature (TJ) is calculated from the ambient
temperature (TA) and power dissipation (PD) as follows:
LT1813CS8: TJ = TA + (PD • 150°C/W)
Power dissipation is composed of two parts. The first is
due to the quiescent supply current and the second is
due to on-chip dissipation caused by the load current.
The worst-case load induced power occurs when the
output voltage is at 1/2 of either supply voltage (or the
maximum swing if less than 1/2 supply voltage). For each
amplifier:
PDMAX = (V + – V – )(ISMAX) + (V +/2)2/RL or
PDMAX = (V + – V – )(ISMAX) + (V + – VOMAX)(VOMAX/RL)
LT1813
U
W
U
U
APPLICATIONS INFORMATION
Example: LT1813 in SO-8 at 70°C, VS = ±5V, RL = 100Ω
PDMAX = (10V)(4.5mA) + (2.5V)2/100Ω = 108mW
TJMAX = 70°C + (2 • 108mW)(150°C/W) = 102°C
Circuit Operation
The LT1813 circuit topology is a true voltage feedback
amplifier that has the slewing behavior of a current feedback amplifier. The operation of the circuit can be understood by referring to the Simplified Schematic. The inputs
are buffered by complementary NPN and PNP emitter
followers which drive a 300Ω resistor. The input voltage
appears across the resistor generating currents that are
mirrored into the high impedance node.
Complementary followers form an output stage that buffers the gain node from the load. The bandwidth is set by
the input resistor and the capacitance on the high impedance node. The slew rate is determined by the current
available to charge the gain node capacitance. This current
is the differential input voltage divided by R1, so the slew
rate is proportional to the input. Highest slew rates are
therefore seen in the lowest gain configurations.
The RC network across the output stage is bootstrapped
when the amplifier is driving a light or moderate load and
has no effect under normal operation. When driving capacitive loads (or a low value resistive load) the network is
incompletely bootstrapped and adds to the compensation
at the high impedance node. The added capacitance slows
down the amplifier which improves the phase margin by
moving the unity-gain cross away from the pole formed by
the output impedance and the capacitive load. The zero
created by the RC combination adds phase to ensure that
the total phase lag does not exceed 180 degrees (zero
phase margin) and the amplifier remains stable. In this
way, the LT1813 is stable with up to 1000pF capacitive
loads in unity gain, and even higher capacitive loads in
higher closed-loop gain configurations.
W
W
SI PLIFIED SCHEMATIC
V+
R1
300Ω
+IN
RC
CC
OUT
–IN
C
V–
1813 SS
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
11
LT1813
U
TYPICAL APPLICATION
Two Op Amp Instrumentation Amplifier
R5
220Ω
R1
10k
R4
10k
R2
1k
R3
1k
–
1/2
LT1813
–
1/2
LT1813
+
–
VOUT
+
VIN
+
(
 R4    1   R2 R3  R2 + R3
GAIN =   1 +   
+
+
R5
 R3    2   R1 R4 

)  = 102


TRIM R5 FOR GAIN
TRIM R1 FOR COMMON MODE REJECTION
BW = 1MHz
1813 TA03
U
PACKAGE DESCRIPTION
MS8 Package
8-Lead Plastic MSOP
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1660)
(LTC DWG # 05-08-1610)
0.118 ± 0.004*
(3.00 ± 0.102)
0.189 – 0.197*
(4.801 – 5.004)
8
8
7 6
0.118 ± 0.004**
(3.00 ± 0.102)
0.193 ± 0.006
(4.90 ± 0.15)
1
2 3
5
0.150 – 0.157**
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
SEATING
PLANE 0.012
(0.30)
0.0256
REF
(0.65)
BSC
1
0.034 ± 0.004
(0.86 ± 0.102)
0° – 6° TYP
0.021 ± 0.006
(0.53 ± 0.015)
6
4
0.040 ± 0.006
(1.02 ± 0.15)
0.007
(0.18)
7
5
0.010 – 0.020
× 45°
(0.254 – 0.508)
0.008 – 0.010
(0.203 – 0.254)
0.006 ± 0.004
(0.15 ± 0.102)
MSOP (MS8) 1098
* DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH,
PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
2
3
0.053 – 0.069
(1.346 – 1.752)
0°– 8° TYP
0.016 – 0.050
(0.406 – 1.270)
0.014 – 0.019
(0.355 – 0.483)
TYP
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
4
0.004 – 0.010
(0.101 – 0.254)
0.050
(1.270)
BSC
SO8 1298
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1360/LT1361/LT1362
Single/Dual/Quad 50MHz, 800V/µs, C-LoadTM Amplifiers
±15V Operation, 1mV Max VOS, 1µA Max IB
LT1363/LT1364/LT1365
Single/Dual/Quad 70MHz, 1000V/µs C-Load Amplifiers
±15V Operation, 1.5mV Max VOS, 2µA Max IB
LT1398/LT1399
Dual/Triple 300MHz Current Feedback Amplifiers
4.5mA Supply Current, 80mA Output Current, Shutdown
C-Load is a trademark of Linear Technology Corporation.
12
Linear Technology Corporation
1813f LT/TP 0999 4K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
 LINEAR TECHNOLOGY CORPORATION 1999
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