LINER LT1354 12mhz, 400v/s op amp Datasheet

LT1354
12MHz, 400V/µs Op Amp
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DESCRIPTION
FEATURES
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The LT ®1354 is a low power, high speed, high slew rate
operational amplifier with outstanding AC and DC performance. The LT1354 has much lower supply current, lower
input offset voltage, lower input bias current, and higher
DC gain than devices with comparable bandwidth. The
circuit topology is a voltage feedback amplifier with the
slewing characteristics of a current feedback amplifier.
The amplifier is a single gain stage with outstanding
settling characteristics which makes the circuit an ideal
choice for data acquisition systems. The output drives a
500Ω load to ±12V with ±15V supplies and a 150Ω load
to ±2.5V on ±5V supplies. The amplifier is also stable with
any capacitive load which makes it useful in buffer or cable
driver applications.
12MHz Gain-Bandwidth
400V/µs Slew Rate
1.25mA Maximum Supply Current
Unity Gain Stable
C-LoadTM Op Amp Drives All Capacitive Loads
10nV/√Hz Input Noise Voltage
800µV Maximum Input Offset Voltage
300nA Maximum Input Bias Current
70nA Maximum Input Offset Current
12V/mV Minimum DC Gain, RL=1k
230ns Settling Time to 0.1%, 10V Step
280ns Settling Time to 0.01%, 10V Step
±12V Minimum Output Swing into 500Ω
±2.5V Minimum Output Swing into 150Ω
Specified at ±2.5V, ±5V, and ±15V
The LT1354 is a member of a family of fast, high performance amplifiers using this unique topology and employing Linear Technology Corporation’s advanced bipolar
complementary processing. For dual and quad amplifier
versions of the LT1354 see the LT1355/LT1356 data
sheet. For higher bandwidth devices with higher supply
current see the LT1357 through LT1365 data sheets.
Singles, duals, and quads of each amplifier are available.
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APPLICATIONS
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Wideband Amplifiers
Buffers
Active Filters
Data Acquisition Systems
Photodiode Amplifiers
, LTC and LT are registered trademarks of Linear Technology Corporation.
C-Load is a trademark of Linear Technology Corporation
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TYPICAL APPLICATION
AV = –1 Large-Signal Response
100kHz, 4th Order Butterworth Filter
6.81k
5.23k
100pF
6.81k
11.3k
VIN
330pF
–
47pF
5.23k
10.2k
LT1354
+
1000pF
–
LT1354
VOUT
+
1354 TA01
1354 TA02
1
LT1354
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ABSOLUTE MAXIMUM RATINGS
Total Supply Voltage (V + to V –) ............................... 36V
Differential Input Voltage (Transient Only, Note 1) ... ±10V
Input Voltage ............................................................±VS
Output Short-Circuit Duration (Note 2) ............ Indefinite
Operating Temperature Range ................ –40°C to 85°C
Specified Temperature Range (Note 6) ... –40°C to 85°C
Maximum Junction Temperature (See Below)
Plastic Package ................................................ 150°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
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PACKAGE/ORDER INFORMATION
TOP VIEW
NULL
1
8
NULL
–IN
2
7
V+
+IN
3
6
VOUT
V–
4
5
NC
ORDER PART
NUMBER
LT1354CN8
ORDER PART
NUMBER
TOP VIEW
NULL
1
8
NULL
–IN
2
7
V+
+IN
3
6
VOUT
V–
4
5
NC
N8 PACKAGE, 8-LEAD PLASTIC DIP
S8 PACKAGE, 8-LEAD PLASTIC SOIC
TJMAX = 150°C, θJA = 130°C/ W
TJMAX = 150°C, θJA = 190°C/ W
LT1354CS8
S8 PART MARKING
1354
Consult factory for Industrial and Military grade parts.
ELECTRICAL CHARACTERISTICS
TA = 25°C, VCM = 0V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
VOS
Input Offset Voltage
IOS
Input Offset Current
IB
Input Bias Current
en
Input Noise Voltage
f = 10kHz
in
Input Noise Current
f = 10kHz
±2.5V to ±15V
RIN
Input Resistance
VCM = ±12V
Differential
±15V
±15V
CIN
Input Capacitance
TYP
MAX
UNITS
±15V
±5V
±2.5V
0.3
0.3
0.4
0.8
0.8
1.0
mV
mV
mV
±2.5V to ±15V
20
70
nA
±2.5V to ±15V
80
300
±2.5V to ±15V
10
nV/√Hz
MIN
70
±15V
+
±15V
±5V
±2.5V
Input Voltage Range –
±15V
±5V
±2.5V
Input Voltage Range
CMRR
Common Mode Rejection Ratio
VCM = ±12V
VCM = ±2.5V
VCM = ±0.5V
PSRR
Power Supply Rejection Ratio
VS = ±2.5V to ±15V
AVOL
Large-Signal Voltage Gain
VOUT = ±12V, RL = 1k
VOUT = ±10V, RL = 500Ω
VOUT = ±2.5V, RL = 1k
VOUT = ±2.5V, RL = 500Ω
VOUT = ±2.5V, RL = 150Ω
VOUT = ±1V, RL = 500Ω
2
VSUPPLY
±15V
±5V
±2.5V
±15V
±15V
±5V
±5V
±5V
±2.5V
12.0
2.5
0.5
nA
0.6
pA/√Hz
160
11
MΩ
MΩ
3
pF
13.4
3.5
1.1
V
V
V
–13.2
– 3.4
– 0.9
–12.0
– 2.5
– 0.5
V
V
V
80
78
68
97
84
75
dB
dB
dB
92
106
dB
12
5
12
5
1
5
36
15
36
15
4
20
V/mV
V/mV
V/mV
V/mV
V/mV
V/mV
LT1354
ELECTRICAL CHARACTERISTICS
TA = 25°C, VCM = 0V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
VSUPPLY
MIN
TYP
VOUT
Output Swing
RL = 1k, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
RL = 150Ω, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
±15V
±15V
±5V
±5V
±2.5V
13.3
12.0
3.5
2.5
1.3
13.8
12.5
4.0
3.1
1.7
±V
±V
±V
±V
±V
IOUT
Output Current
VOUT = ±12V
VOUT = ±2.5V
±15V
±5V
24.0
16.7
30
25
mA
mA
ISC
Short-Circuit Current
VOUT = 0V, VIN = ±3V
±15V
30
42
mA
SR
Slew Rate
AV = –2, (Note 3)
±15V
±5V
200
70
400
120
V/µs
V/µs
Full Power Bandwidth
10V Peak, (Note 4)
3V Peak, (Note 4)
±15V
±5V
6.4
6.4
MHz
MHz
GBW
Gain-Bandwidth
f = 200kHz, RL = 2k
±15V
±5V
±2.5V
12.0
10.5
9.0
MHz
MHz
MHz
tr, tf
Rise Time, Fall Time
AV = 1, 10%-90%, 0.1V
±15V
±5V
14
17
ns
ns
Overshoot
AV = 1, 0.1V
±15V
±5V
20
18
%
%
Propagation Delay
50% VIN to 50% VOUT, 0.1V
±15V
±5V
16
19
ns
ns
Settling Time
10V Step, 0.1%, AV = –1
10V Step, 0.01%, AV = –1
5V Step, 0.1%, AV = –1
5V Step, 0.01%, AV = –1
±15V
±15V
±5V
±5V
230
280
240
380
ns
ns
ns
ns
Differential Gain
f = 3.58MHz, AV = 2, RL = 1k
±15V
±5V
2.2
2.1
%
%
Differential Phase
f = 3.58MHz, AV = 2, RL = 1k
±15V
±5V
3.1
3.1
Deg
Deg
RO
Output Resistance
AV = 1, f = 100kHz
±15V
0.7
IS
Supply Current
±15V
±5V
1.0
0.9
1.25
1.20
mA
mA
TYP
MAX
UNITS
ts
9.0
7.5
MAX
UNITS
Ω
0°C ≤ TA ≤ 70°C, VCM = 0V unless otherwise noted.
SYMBOL
PARAMETER
VOS
Input Offset Voltage
Input VOS Drift
IOS
CONDITIONS
(Note 5)
Input Offset Current
IB
Input Bias Current
CMRR
Common Mode Rejection Ratio
VCM = ±12V
VCM = ±2.5V
VCM = ±0.5V
PSRR
Power Supply Rejection Ratio
VS = ±2.5V to ±15V
AVOL
Large-Signal Voltage Gain
VOUT = ±12V, RL = 1k
VOUT = ±10V, RL = 500Ω
VOUT = ±2.5V, RL = 1k
VOUT = ±2.5V, RL = 500Ω
VOUT = ±2.5V, RL = 150Ω
VOUT = ±1V, RL = 500Ω
VSUPPLY
MIN
±15V
±5V
±2.5V
●
●
●
±2.5V to ±15V
●
±2.5V to ±15V
●
±2.5V to ±15V
●
±15V
±5V
±2.5V
●
●
●
±15V
±15V
±5V
±5V
±5V
±2.5V
1.0
1.0
1.2
5
79
77
67
8
mV
mV
mV
µV/°C
100
nA
450
nA
dB
dB
dB
●
90
dB
●
●
●
●
●
●
10.0
3.3
10.0
3.3
0.6
3.3
V/mV
V/mV
V/mV
V/mV
V/mV
V/mV
3
LT1354
ELECTRICAL CHARACTERISTICS
0°C ≤ TA ≤ 70°C, VCM = 0V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
VSUPPLY
VOUT
Output Swing
RL = 1k, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
RL = 150Ω, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
±15V
±15V
±5V
±5V
±2.5V
●
●
●
●
●
13.2
11.5
3.4
2.3
1.2
MIN
TYP
MAX
UNITS
±V
±V
±V
±V
±V
IOUT
Output Current
VOUT = ±11.5V
VOUT = ±2.3V
±15V
±5V
●
●
23.0
15.3
mA
mA
ISC
Short-Circuit Current
VOUT = 0V, VIN = ±3V
±15V
●
24
mA
SR
Slew Rate
AV = –2, (Note 3)
±15V
±5V
●
●
150
60
V/µs
V/µs
GBW
Gain-Bandwidth
f = 200kHz, RL = 2k
±15V
±5V
●
●
7.5
6.0
MHz
MHz
IS
Supply Current
±15V
±5V
●
●
1.45
1.40
mA
mA
MAX
UNITS
1.5
1.5
1.7
mV
mV
mV
–40°C ≤ TA ≤ 85°C, VCM = 0V unless otherwise noted. (Note 6)
SYMBOL
PARAMETER
VOS
Input Offset Voltage
Input VOS Drift
IOS
CONDITIONS
(Note 5)
Input Offset Current
VSUPPLY
MIN
TYP
±15V
±5V
±2.5V
●
●
●
±2.5V to ±15V
●
±2.5V to ±15V
●
±2.5V to ±15V
●
±15V
±5V
±2.5V
●
●
●
78
76
66
dB
dB
dB
●
90
dB
5
8
µV/°C
200
nA
550
nA
IB
Input Bias Current
CMRR
Common Mode Rejection Ratio
VCM = ±12V
VCM = ±2.5V
VCM = ±0.5V
PSRR
Power Supply Rejection Ratio
VS = ±2.5V to ±15V
AVOL
Large-Signal Voltage Gain
VOUT = ±12V, RL = 1k
VOUT = ±10V, RL = 500Ω
VOUT = ±2.5V, RL = 1k
VOUT = ±2.5V, RL = 500Ω
VOUT = ±2.5V, RL = 150Ω
VOUT = ±1V, RL = 500Ω
±15V
±15V
±5V
±5V
±5V
±2.5V
●
●
●
●
●
●
7.0
1.7
7.0
1.7
0.4
1.7
V/mV
V/mV
V/mV
V/mV
V/mV
V/mV
VOUT
Output Swing
RL = 1k, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
RL = 150Ω, VIN = ±40mV
RL = 500Ω, VIN = ±40mV
±15V
±15V
±5V
±5V
±2.5V
●
●
●
●
●
13.0
11.0
3.4
2.1
1.2
±V
±V
±V
±V
±V
IOUT
Output Current
VOUT = ±11V
VOUT = ±2.1V
±15V
±5V
●
●
22
14
mA
mA
ISC
Short-Circuit Current
VOUT = 0V, VIN = ±3V
±15V
●
23
mA
SR
Slew Rate
AV = –2, (Note 3)
±15V
±5V
●
●
120
50
V/µs
V/µs
GBW
Gain Bandwith
f = 200kHz, RL = 2k
±15V
±5V
●
●
7.0
5.5
MHz
MHz
IS
Supply Current
±15V
±5V
●
●
4
1.50
1.45
mA
mA
LT1354
ELECTRICAL CHARACTERISTICS
The ● denotes specifications that apply over the full specified temperature
range.
Note 1: Differential inputs of ±10V are appropriate for transient operation
only, such as during slewing. Large, sustained differential inputs will
cause excessive power dissipation and may damage the part. See Input
Considerations in the Applications Information section of this data sheet
for more dutails.
Note 2: A heat sink may be required to keep the junction temperature
below absolute maximum when the output is shorted indefinitely.
Note 3: Slew rate is measured between ±10V on the output with ±6V input
for ±15V supplies and ±1V on the output with ±1.75V input for ±5V supplies.
Note 4: Full power bandwidth is calculated from the slew rate
measurement: FPBW = SR/2πVP.
Note 5: This parameter is not 100% tested.
Note 6: The LT1354 is designed, characterized and expected to meet these
extended temperature limits, but is not tested at – 40°C and at 85°C.
Guaranteed I grade parts are available; consult factory.
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TYPICAL PERFORMANCE CHARACTERISTICS
Supply Current vs Supply Voltage
and Temperature
V+
1.4
200
125°C
1.0
25°C
0.8
–55°C
0.6
–1.0
INPUT BIAS CURRENT (nA)
COMMON-MODE RANGE (V)
1.2
VS = ±15V
TA = 25°C
IB+ + IB–
IB = ————
2
TA = 25°C
∆VOS < 1mV
–0.5
SUPPLY CURRENT (mA)
Input Bias Current vs
Input Common-Mode Voltage
Input Common-Mode Range vs
Supply Voltage
–1.5
–2.0
2.0
1.5
1.0

150

100
50
0
0.5
V–
0.4
5
10
15
SUPPLY VOLTAGE (±V)
20
0
5
10
15
SUPPLY VOLTAGE (±V)
1354 G01

125
100
75
50
VS = ±15V
TA = 25°C
AV = 101
RS = 100k
in
10
TA = 25°C
en
1
25
0
– 50
1
–25
0
25
50
75
TEMPERATURE (°C)
100
125
1354 G04
100
10
100
INPUT VOLTAGE NOISE (nV/√Hz)
INPUT BIAS CURRENT (nA)
150
Open-Loop Gain vs
Resistive Load
10
100
1k
10k
FREQUENCY (Hz)
0.1
100k
1354 G05
INPUT CURRENT NOISE (pA/√Hz)

175
15
1354 G03
Input Noise Spectral Density
VS = ±15V
IB+ + IB–
IB = ————
2
–10
–5
0
5
10
INPUT COMMON-MODE VOLTAGE (V)
1354 G02
Input Bias Current vs
Temperature
200
–50
–15
20
VS = ±15V
VS = ±5V
90
OPEN-LOOP GAIN (dB)
0
80
70
60
50
10
100
1k
LOAD RESISTANCE (Ω)
10k
1354 G06
5
LT1354
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Output Voltage Swing vs
Supply Voltage
Open-Loop Gain vs Temperature
V + – 0.5
V+
97
RL = 1k
VO = ±12V
VS = ±15V
RL = 1k
94
93
92
91
90
–2
RL = 500Ω
–3
3
RL = 500Ω
2
1
89
88
– 50
0
25
50
75
TEMPERATURE (°C)
100
125
0
20
10
SINK
40
SOURCE
6
10mV
4
1mV
2
0
–2
–4
10mV
30
–6
25
1mV
100
150
200
250
SETTLING TIME (ns)
300
PHASE
VS = ±15V
GAIN
0
100k
1M
10M
FREQUENCY (Hz)
100M
1354 G13
6
60
VS = ±5V
30
20
80
VS = ±15V
40
–10
10k
40
VS = ±5V
20
0
16
46
15
44
14
42
13
40
12
38
11
36
GAIN-BANDWIDTH
34
TA = 25°C
9
8
1M
10M
FREQUENCY (Hz)
48
PHASE MARGIN
10
TA = 25°C
AV = –1
RF = RG = 2k
100k
350
50
17
100
10
0.1
300
18
GAIN-BANDWIDTH (MHz)
AV = 1
150
200
250
SETTLING TIME (ns)
1355/1356 G12
120
60
GAIN (dB)
1
100
100M
1354 G14
0
5
10
15
SUPPLY VOLTAGE (±V)
32
30
20
1354 G15
PHASE MARGIN (DEG)
AV = 10
10mV
Gain-Bandwidth and Phase
Margin vs Supply Voltage
70
VS = ±15V
TA = 25°C
10
1mV
50
Gain and Phase vs Frequency
50
0.01
10k
350
PHASE (DEG)
OUTPUT IMPEDANCE (Ω)
100
–2
–4
1354 G11
Output Impedance vs Frequency
AV = 100
1mV
0
–10
50
1354 G10
1k
10mV
2
–8
–10
125
4
–6
–8
100
VS = ±15V
AV = –1
8
OUTPUT SWING (V)
OUTPUT SWING (V)
OUTPUT SHORT-CIRCUIT CURRENT (mA)
45
0
25
50
75
TEMPERATURE (°C)
– 40°C
1.5
Settling Time vs Output Step
(Inverting)
VS = ±15V
AV = 1
8
50
–25
25°C
2.0
1354 G09
6
20
– 50
85°C
V – +0.5
– 50 – 40 –30 –20 –10 0 10 20 30 40 50
OUTPUT CURRENT (mA)
10
55
35
25°C
2.5
Settling Time vs Output Step
(Noninverting)
VS = ±5V
60
–2.5
1354 G08
Output Short-Circuit Current vs
Temperature
65
–2.0
1.0
5
10
15
SUPPLY VOLTAGE (±V)
1354 G07
– 40°C
–1.5
RL = 1k
V–
–25
85°C
VS = ± 5V
VIN = 100mV
–1.0
–1
OUTPUT VOLTAGE SWING (V)
95
TA = 25°C
OUTPUT VOLTAGE SWING (V)
96
OPEN-LOOP GAIN (dB)
Output Voltage Swing vs
Load Current
LT1354
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Gain-Bandwidth and Phase
Margin vs Temperature
PHASE MARGIN
VS = ±5V
15
4
48
3
46
14
44
13
42
GAIN-BANDWIDTH
VS = ±15V
12
40
11
38
10
GAIN-BANDWIDTH
VS = ±5V
9
8
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
5
TA = 25°C
AV = 1
RL = 2k
3
2
2
±15V
1
0
–1
±5V
–2
36
–3
34
–4
–3
10M
1M
FREQUENCY (Hz)
100M
C = 500pF
2
C = 100pF
0
C = 50pF
–2
C=0
–4
–6
–8
–10
100k
1M
10M
FREQUENCY (Hz)
120
VS = ±15V
TA = 25°C
80
+PSRR
–PSRR
60
40
20
0
100
100M
Slew Rate vs Supply Voltage
10k 100k
1M
FREQUENCY (Hz)
10M
40
20
15
SR+ + SR–
SR = —————
2
150
1354 G22
50
– 50
100M
VS = ±15V
AV = –1
RF = RG = 2k
SR+ + SR–
SR = —————
2
TA = 25°C
400
SLEW RATE (V/µs)
200
10M
Slew Rate vs Input Level
250
VS = ± 5V
100
0
100k
1M
FREQUENCY (Hz)
500
VS = ±15V
100
10k
1354 G21
AV = –2
SLEW RATE (V/µs)
SLEW RATE (V/µs)
60
1k
300
200
5
10
SUPPLY VOLTAGE (±V)
80
Slew Rate vs Temperature
300
0
100
100M
350
400
VS = ±15V
TA = 25°C
1354 G20
600
AV = –1
RF = RG = 2k
SR+ + SR–
SR = —————
2
TA = 25°C
100M
0
1k
1354 G19
500
10M
1M
FREQUENCY (Hz)
Common-Mode Rejection Ratio
vs Frequency
COMMON-MODE REJECTION RATIO (dB)
POWER SUPPLY REJECTION RATIO (dB)
VOLTAGE MAGNITUDE (dB)
4
±15V
1354 G18
100
C = 1000pF
±2.5V
–5
100k
Power Supply Rejection Ratio
vs Frequency
10
6
±5V
1354 G17
Frequency Response vs
Capacitive Load
VS = ±15V
TA = 25°C
AV = –1
0
–1
–4
1354 G16
8
1
–2
±2.5V
–5
100k
32
125
TA = 25°C
AV = –1
RF = RG = 2k
4
GAIN (dB)
16
50
GAIN (dB)
PHASE MARGIN
VS = ±15V
PHASE MARGIN (DEG)
GAIN-BANDWIDTH (MHz)
5
52
18
17
Frequency Response vs
Supply Voltage (AV = –1)
Frequency Response vs
Supply Voltage (AV = 1)
300
200
100
0
–25
0
25
50
75
TEMPERATURE (°C)
100
125
1354 G23
0
2
4
6 8 10 12 14 16 18 20
INPUT LEVEL (VP-P)
1354 G24
7
LT1354
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TYPICAL PERFORMANCE CHARACTERISTICS
Total Harmonic Distortion
vs Frequency
Undistorted Output Swing vs
Frequency (±15V)
30
TA = 25°C
VO = 3VRMS
RL = 2k
OUTPUT VOLTAGE (VP-P)
AV = –1
0.001
AV = 1
100
AV = –1
25
0.01
0.0001
10
10
20
AV = 1
15
10
5
VS = ±15V
RL = 5k
AV = 1,
1% MAX DISTORTION
AV = –1,
4% MAX DISTORTION
0
100k
100k
1k
10k
FREQUENCY (Hz)
OUTPUT VOLTAGE (VP-P)
0.1
1M
FREQUENCY (Hz)
Capacitive Load Handling
DIFFERENTIAL PHASE (DEGREES)
HARMONIC DISTORTION (dB)
–60
2ND HARMONIC
–70
400k
1M 2M
FREQUENCY (Hz)
4M
10M
2.0
3.4
AV = 2
RL = 1k
TA = 25°C
1.5
3.3
DIFFERENTIAL PHASE
3.2
3.1
±5
±10
SUPPLY VOLTAGE (V)
1354 G28
±15
TA = 25°C
VS = ±15V
1354 TA31
AV = 1
50
AV = –1
0
10p
100p
1000p 0.01µ
0.1µ
CAPACITIVE LOAD (F)
1µ
1354 G30
1354 G29
Small-Signal Transient
(AV = –1)
Small-Signal Transient
(AV = 1)
DIFFERENTIAL PHASE (PERCENT)
–50
10M
100
DIFFERENTIAL GAIN
3RD HARMONIC
1M
FREQUENCY (Hz)
1354 G27
2.5
–40
8
0
100k
10M
–20
–80
100k 200k
VS = ±5V
RL = 5k
AV = 1,
2% MAX DISTORTION
AV = –1,
3% MAX DISTORTION
4
Differential Gain and Phase
vs Supply Voltage
2nd and 3rd Harmonic Distortion
vs Frequency
–30
AV = 1
6
1355/1356 G26
1354 G25
VS = ±15V
VO = 2VP-P
RL = 2k
AV = 2
AV = –1
8
2
OVERSHOOT (%)
TOTAL HARMONIC DISTORTION (%)
Undistorted Output Swing vs
Frequency (±5V)
Small-Signal Transient
(AV = –1, CL = 1000pF)
1354 TA32
1354 TA33
LT1354
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TYPICAL PERFORMANCE CHARACTERISTICS
Large-Signal Transient
(AV = 1)
Large-Signal Transient
(AV = 1, CL = 10,000pF)
Large-Signal Transient
(AV = –1)
1354 TA34
1354 TA35
1354 TA36
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APPLICATIONS INFORMATION
The LT1354 may be inserted directly into many high
speed amplifier applications improving both DC and AC
performance, provided that the nulling circuitry is
removed. The suggested nulling circuit for the LT1354 is
shown below.
Offset Nulling
The parallel combination of the feedback resistor and gain
setting resistor on the inverting input can combine with
the input capacitance to form a pole which can cause
peaking or oscillations. For feedback resistors greater
than 5kΩ, a parallel capacitor of value
CF > (RG • CIN)/RF
V+
3
7
+
6
LT1354
2
4
–
8
1
10k
should be used to cancel the input pole and optimize
dynamic performance. For unity-gain applications where
a large feedback resistor is used, CF should be greater
than or equal to CIN.
Capacitive Loading
V–
1354 AI01
Layout and Passive Components
The LT1354 amplifier is easy to apply and tolerant of less
than ideal layouts. For maximum performance (for
example fast settling time) 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). Sockets should
be avoided when maximum frequency performance is
required, although low profile sockets can provide
reasonable performance up to 50MHz. For more details
see Design Note 50.
The LT1354 is stable with any capacitive load. 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 as shown in the
typical performance curves.The photo of the small-signal
response with 1000pF load shows 43% peaking. The large
signal response with a 10,000pF load shows the output
slew rate being limited to 5V/µs by the short-circuit
current. 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.
9
LT1354
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APPLICATIONS INFORMATION
Input Considerations
Each of the LT1354 inputs is the base of an NPN and
a 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 bias current can be positive
or negative. The offset current does not depend on
NPN/PNP 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 transient differential input voltages up to 10V without damage and need no clamping or
source resistance for protection. Differential inputs, however, generate large supply currents (tens of mA) as
required for high slew rates. If the device is used with
sustained differential inputs, the average supply current
will increase, excessive power dissipation will result and
the part may be damaged. The part should not be used as
a comparator, peak detector or other open-loop application with large, sustained differential inputs. Under
normal, closed-loop operation, an increase of power
dissipation is only noticeable in applications with large
slewing outputs and is proportional to the magnitude of
the differential input voltage and the percent of the time
that the inputs are apart. Measure the average supply
current for the application in order to calculate the power
dissipation.
Power Dissipation
The LT1354 combines high speed and large output drive
in a small package. Because of the wide supply voltage
range, 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:
LT1354CN8: TJ = TA + (PD • 130°C/W)
LT1354CS8: TJ = TA + (PD • 190°C/W)
Worst case power dissipation occurs at the maximum
supply current and when the output voltage is at 1/2 of
10
either supply voltage (or the maximum swing if less than
1/2 supply voltage). Therefore PDMAX is:
PDMAX = (V+ – V –)(ISMAX) + (V+/2)2/RL
Example: LT1354CS8 at 70°C, VS = ±15V, RL = 100Ω
(Note: the minimum short-circuit current at 70°C is
24mA, so the output swing is guaranteed only to 2.4V with
100Ω.)
PDMAX = (30V • 1.45mA) + (15V–2.4V)(24mA) = 346mW
TJMAX = 70°C + (346mW • 190°C/W) = 136°C
Circuit Operation
The LT1354 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 an 800Ω resistor. The input voltage
appears across the resistor generating currents which are
mirrored into the high impedance node. Complementary
followers form an output stage which 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. For example,
a 10V output step in a gain of 10 has only a 1V input step,
whereas the same output step in unity gain has a 10 times
greater input step. The curve of Slew Rate vs Input Level
illustrates this relationship. The LT1354 is tested for slew
rate in a gain of –2 so higher slew rates can be expected
in gains of 1 and –1, and lower slew rates in higher 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 a
capacitive load (or a low value resistive load) the network
is incompletely bootstrapped and adds to the compensation at the high impedance node. The added capacitance
LT1354
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APPLICATIONS INFORMATION
slows down the amplifier which improves the phase
margin by moving the unity gain frequency 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 even for very large load capacitances, the
total phase lag can never exceed 180 degrees (zero phase
margin) and the amplifier remains stable.
W
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SI PLIFIED SCHE ATIC
V+
R1
800Ω
+IN
RC
OUT
–IN
C
CC
V–
1354 SS01
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PACKAGE DESCRIPTION
Dimensions in inches (millimeters) unless otherwise noted.
N8 Package
8-Lead PDIP (Narrow 0.300)
(LTC DWG # 05-08-1510)
0.300 – 0.325
(7.620 – 8.255)
0.009 – 0.015
(0.229 – 0.381)
(
+0.035
0.325 –0.015
+0.889
8.255
–0.381
)
0.045 – 0.065
(1.143 – 1.651)
0.130 ± 0.005
(3.302 ± 0.127)
0.065
(1.651)
TYP
0.100 ± 0.010
(2.540 ± 0.254)
0.400*
(10.160)
MAX
8
7
6
5
1
2
3
4
0.255 ± 0.015*
(6.477 ± 0.381)
0.125
(3.175) 0.020
MIN (0.508)
MIN
0.018 ± 0.003
(0.457 ± 0.076)
N8 1197
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
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
LT1354
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PACKAGE DESCRIPTION
Dimensions in inches (millimeters) unless otherwise noted.
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
0.189 – 0.197*
(4.801 – 5.004)
0.010 – 0.020
× 45°
(0.254 – 0.508)
8
0.053 – 0.069
(1.346 – 1.752)
0.008 – 0.010
(0.203 – 0.254)
5
6
0.004 – 0.010
(0.101 – 0.254)
0°– 8° TYP
0.016 – 0.050
0.406 – 1.270
7
0.150 – 0.157**
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
0.050
(1.270)
TYP
0.014 – 0.019
(0.355 – 0.483)
*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
1
2
3
4
SO8 0996
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TYPICAL APPLICATIONS
100kHz, 4th Order Butterworth Filter
(Sallen-Key)
Instrumentation Amplifier
R5
432Ω
R1
20k
C4
1000pF
C2
330pF
R2
2k
–
–
R3
2k
–
LT1354
–
R4
20k
+
+
VIN
–
VOUT
LT1354
+
VIN
LT1354
R1
2.87k
R2
26.7k
C1
100pF
VOUT
+
LT1354
R3
2.43k
R4
15.4k
C3
68pF
1354 TA04
+
R4  1  R2 R3  R2 + R3 
1 +
 = 104
+
+
R3  2  R1 R4 
R5 


TRIM R5 FOR GAIN
TRIM R1 FOR COMMON MODE REJECTION
BW = 120kHz
AV =
1354 TA03
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1355/LT1356
Dual/Quad 1mA, 12MHz, 400V/µs Op Amp
Good DC Precision, Stable with All Capacitive Loads
LT1357
2mA, 25MHz, 600V/µs Op Amp
Good DC Precision, Stable with All Capacitive Loads
LT1358/LT1359
Dual/Quad 2mA, 25MHz, 600V/µs Op Amp
Good DC Precision, Stable with All Capacitive Loads
12
Linear Technology Corporation
1354fa LT/TP 0598 REV A 2K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
 LINEAR TECHNOLOGY CORPORATION 1994
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