LT1226
Low Noise Very High Speed
Operational Amplifier
FEATURES
s
s
s
s
s
s
s
s
s
s
s
DESCRIPTIO
Gain of 25 Stable
1GHz Gain Bandwidth
400V/µs Slew Rate
2.6nV/√Hz Input Noise Voltage
50V/mV Minimum DC Gain, R
L
= 500Ω
1mV Maximum Input Offset Voltage
±12V
Minimum Output Swing into 500Ω
Wide Supply Range
±2.5V
to
±15V
7mA Supply Current
100ns Settling Time to 0.1%, 10V Step
Drives All Capacitive Loads
The LT1226 is a low noise, very high speed operational
amplifier with excellent DC performance. The LT1226
features low input offset voltage and high DC gain. The
circuit is a single gain stage with outstanding settling
characteristics. The fast settling time makes the circuit an
ideal choice for data acquisition systems. The output is
capable of driving a 500Ω load to
±12V
with
±15V
supplies
and a 150Ω load to
±3V
on
±5V
supplies. The circuit is also
capable of driving large capacitive loads which makes it
useful in buffer or cable driver applications.
The LT1226 is a member of a family of fast, high per-
formance amplifiers that employ Linear Technology
Corporation’s advanced bipolar complementary
processing.
APPLICATI
s
s
s
s
s
s
S
Wideband Amplifiers
Buffers
Active Filters
Video and RF Amplification
Cable Drivers
Data Acquisition Systems
TYPICAL APPLICATI
V
+
Photodiode Preamplifier, A
V
= 5.1kΩ, BW = 15MHz
Gain of +25 Pulse Response
+
51Ω
LT1226
–
5.1k
51Ω
LT1226 TA01
U
LT1226 TA02
UO
UO
1
LT1226
ABSOLUTE
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
NULL
–IN
+IN
V
–
1
2
3
4
8
7
6
5
NULL
V
+
OUT
NC
Total Supply Voltage (V
+
to V
–
) ............................... 36V
Differential Input Voltage .........................................
±6V
Input Voltage ............................................................±V
S
Output Short Circuit Duration (Note 1) ............ Indefinite
Operating Temperature Range
LT1226C ................................................ 0°C to 70°C
Maximum Junction Temperature
Plastic Package .............................................. 150°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec.)................. 300°C
ORDER PART
NUMBER
LT1226CN8
LT1226CS8
S8 PART MARKING
1226
N8 PACKAGE
S8 PACKAGE
8-LEAD PLASTIC DIP 8-LEAD PLASTIC SOIC
LT1226 PO01
ELECTRICAL CHARACTERISTICS
SYMBOL
V
OS
I
OS
I
B
e
n
i
n
R
IN
C
IN
PARAMETER
Input Offset Voltage
Input Offset Current
Input Bias Current
Input Noise Voltage
Input Noise Current
Input Resistance
Input Capacitance
Input Voltage Range +
Input Voltage Range –
CMRR
PSRR
A
VOL
V
OUT
I
OUT
SR
GBW
t
r
, t
f
Common-Mode Rejection Ratio
Power Supply Rejection Ratio
Large Signal Voltage Gain
Output Swing
Output Current
Slew Rate
Full Power Bandwidth
Gain Bandwidth
Rise Time, Fall Time
Overshoot
Propagation Delay
t
s
Settling Time
Differential Gain
Differential Phase
R
O
I
S
Output Resistance
Supply Current
V
S
=
±15V,
T
A
= 25°C, V
CM
= 0V unless otherwise noted.
MIN
TYP
0.3
100
4
MAX
1.0
400
8
UNITS
mV
nA
µA
nV/√Hz
pA/√Hz
MΩ
kΩ
pF
V
– 12
V
dB
dB
V/mV
±V
mA
V/µs
MHz
GHz
ns
%
ns
ns
%
Deg
Ω
9
mA
CONDITIONS
(Note 2)
f = 10kHz
f = 10kHz
V
CM
=
±12V
Differential
24
2.6
1.5
40
15
2
12
14
– 13
103
110
150
13.3
40
400
6.4
1
5.5
35
5.5
100
0.7
0.6
3.1
7
V
CM
=
±12V
V
S
=
±5V
to
±15V
V
OUT
=
±10V,
R
L
= 500Ω
R
L
= 500Ω
V
OUT
=
±12V
(Note 3)
10V Peak, (Note 4)
f = 1MHz
A
VCL
= + 25,10% to 90%, 0.1V
A
VCL
= +25, 0.1V
50% V
IN
to 50% V
OUT
10V Step, 0.1%, A
V
= – 25
f = 3.58MHz, A
V
= +25, R
L
= 150Ω
f = 3.58MHz, A
V
= +25, R
L
= 150Ω
A
VCL
= +25, f = 1MHz
94
94
50
12.0
24
250
2
U
W
U
U
W W
W
LT1226
ELECTRICAL CHARACTERISTICS
V
S
=
±5V,
T
A
= 25°C, V
CM
= 0V unless otherwise noted.
SYMBOL
V
OS
I
OS
I
B
PARAMETER
Input Offset Voltage
Input Offset Current
Input Bias Current
Input Voltage Range +
Input Voltage Range –
CMRR
A
VOL
V
OUT
I
OUT
SR
GBW
t
r
, t
f
Common-Mode Rejection Ratio
Large Signal Voltage Gain
Output Voltage
Output Current
Slew Rate
Full Power Bandwidth
Gain Bandwidth
Rise Time, Fall Time
Overshoot
Propagation Delay
t
s
I
S
Settling Time
Supply Current
V
CM
=
±2.5V
V
OUT
=
±2.5V,
R
L
= 500Ω
V
OUT
=
±2.5V,
R
L
= 150Ω
R
L
= 500Ω
R
L
= 150Ω
V
OUT
=
±3V
(Note 3)
3V Peak, (Note 4)
f = 1MHz
A
VCL
= +25, 10% to 90%, 0.1V
A
VCL
= +25, 0.1V
50% V
IN
to 50% V
OUT
– 2.5V to 2.5V, 0.1%, A
V
= – 24
94
50
3.0
3.0
20
2.5
CONDITIONS
(Note 2)
MIN
TYP
1.0
100
4
4
–3
103
100
75
3.7
3.3
40
250
13.3
700
8
25
8
60
7
9
–2.5
MAX
1.4
400
8
UNITS
mV
nA
µA
V
V
dB
V/mV
V/mV
±
V
±
V
mA
V/µs
MHz
MHz
ns
%
ns
ns
mA
ELECTRICAL CHARACTERISTICS
SYMBOL
V
OS
PARAMETER
Input Offset Voltage
Input V
OS
Drift
I
OS
I
B
CMRR
PSRR
A
VOL
V
OUT
I
OUT
SR
I
S
Input Offset Current
Input Bias Current
Common-Mode Rejection Ratio
Power Supply Rejection Ratio
Large Signal Voltage Gain
Output Swing
Output Current
Slew Rate
Supply Current
CONDITIONS
0°C
≤
T
A
≤
70°C, V
CM
= 0V unless otherwise noted.
MIN
TYP
0.3
1.0
6
100
4
92
92
35
35
12.0
3.0
24
20
250
103
110
150
100
13.3
3.3
40
40
400
7
10.5
MAX
1.3
1.8
600
9
UNITS
mV
mV
µV/°C
nA
µA
dB
dB
V/mV
V/mV
±
V
±
V
mA
mA
V/µs
mA
V
S
=
±15V,
(Note 2)
V
S
=
±
5V, (Note 2)
V
S
=
±15V
and V
S
=
±
5V
V
S
=
±15V
and V
S
=
±
5V
V
S
=
±15V,
V
CM
=
±12V
and V
S
=
±
5V, V
CM
=
±
2.5V
V
S
=
±5V
to
±15V
V
S
=
±15V,
V
OUT
=
±10V,
R
L
= 500Ω
V
S
=
±5V,
V
OUT
=
±2.5V,
R
L
= 500Ω
V
S
=
±15V,
R
L
= 500Ω
V
S
=
±5V,
R
L
= 500Ω or 150Ω
V
S
=
±15V,
V
OUT
=
±12V
V
S
=
±5V,
V
OUT
=
±3V
V
S
=
±15V,
(Note 3)
V
S
=
±15V
and V
S
=
±
5V
Note 1:
A heat sink may be required to keep the junction temperature
below absolute maximum when the output is shorted indefinitely.
Note 2:
Input offset voltage is tested with automated test equipment
in <1 second.
Note 3:
Slew rate is measured between
±10V
on an output swing of
±12V
on
±15V
supplies, and
±2V
on an output swing of
±3.5V
on
±5V
supplies.
Note 4:
Full power bandwidth is calculated from the slew rate
measurement: FPBW = SR/2πVp.
3
LT1226
TYPICAL PERFOR A CE CHARACTERISTICS
Input Common Mode Range vs
Supply Voltage
20
MAGNITUDE OF INPUT VOLTAGE (V)
SUPPLY CURRENT (mA)
15
7.5
OUTPUT VOLTAGE SWING (V)
T
A
= 25°C
∆V
OS
< 1mV
10
+V
CM
5
–V
CM
0
0
5
10
15
20
LT1226 TPC01
SUPPLY VOLTAGE (±V)
Output Voltage Swing vs
Resistive Load
30
OUTPUT VOLTAGE SWING (Vp-p)
25
20
15
10
5
0
10
T
A
= 25°C
∆V
OS
= 30mV
INPUT BIAS CURRENT (µA)
V
S
= ±15V
OPEN LOOP GAIN (dB)
V
S
= ±5V
100
1k
LOAD RESISTANCE (Ω)
LT1226 TPC04
Supply Current vs Temperature
10
V
S
= ±15V
9
4.75
5.0
OUTPUT SHORT CIRCUIT CURRENT (mA)
INPUT BIAS CURRENT (µA)
SUPPLY CURRENT (mA)
8
7
6
5
4
–50
–25
0
25
50
75
TEMPERATURE (°C)
LT1226 TPC07
4
U W
100
Supply Current vs Supply Voltage
8.0
T
A
= 25°C
15
20
Output Voltage Swing vs
Supply Voltage
T
A
= 25°C
R
L
= 500Ω
∆V
OS
= 30mV
+V
SW
10
–V
SW
5
7.0
6.5
6.0
0
5
10
15
20
LT1226 TPC02
0
0
5
10
15
20
LT1226 TPC03
SUPPLY VOLTAGE (±V)
SUPPLY VOLTAGE (±V)
Input Bias Current vs Input
Common Mode Voltage
5.0
V
S
= ±15V
T
A
= 25°C
I
B+
+ I
B–
I
B
=
2
120
Open Loop Gain vs
Resistive Load
T
A
= 25°C
110
V
S
= ±15V
4.5
100
4.0
V
S
= ±5V
90
3.5
80
10k
3.0
–15
70
–10
–5
0
5
10
15
10
100
1k
10k
LT1226 TPC06
INPUT COMMON MODE VOLTAGE (V)
LT1226 TPC05
LOAD RESISTANCE (Ω)
Input Bias Current vs Temperature
55
V
S
= ±15V
I +I
I
B
=
B+ B–
2
Output Short Circuit Current vs
Temperature
V
S
= ±5V
50
45
40
SOURCE
35
30
25
–50
SINK
4.5
4.25
4.0
3.75
3.5
–50
125
–25
0
25
50
75
100
125
–25
0
25
50
75
100
125
TEMPERATURE (°C)
LT1226 TPC08
TEMPERATURE (°C)
LT1226 TPC09
LT1226
TYPICAL PERFOR A CE CHARACTERISTICS
Input Noise Spectral Density
1000
10
POWER SUPPLY REJECTION RATIO (dB)
COMMON MODE REJECTION RATIO (dB)
INPUT VOLTAGE NOISE (nV/√Hz)
i
n
100
V
S
= ±15V
T
A
= 25°C
A
V
= +101
R
S
= 100kΩ
1.0
10
e
n
1
10
100
1k
FREQUENCY (Hz)
LT1226 TPC10
10k
Voltage Gain and Phase vs
Frequency
110
V
S
= ±15V
90
80
V
S
= ±5V
70
V
S
= ±5V
V
S
= ±15V
60
100
10
8
6
OUTPUT SWING (V)
VOLTAGE GAIN (dB)
4
2
0
–2
–4
–6
–8
A
V
= –25
A
V
= +25
VOLTAGE MAGNITUDE (dB)
50
30
T
A
= 25°C
10
100
1k
10k
100k 1M
FREQUENCY (Hz)
10M
Closed Loop Output Impedance vs
Frequency
100
V
S
= ±15V
T
A
= 25°C
A
V
= +25
GAIN BANDWIDTH (MHz)
OUTPUT IMPEDANCE (Ω)
10
1.05
1.0
0.95
0.90
SLEW RATE (V/µs)
1
0.1
0.01
10k
100k
1M
FREQUENCY (Hz)
10M
U W
LT1226 TPC13
LT1226 TPC16
Power Supply Rejection Ratio vs
Frequency
120
V
S
= ±15V
T
A
= 25°C
100
Common Mode Rejection Ratio vs
Frequency
120
100
80
60
40
20
0
1k
10k
100k
1M
FREQUENCY (Hz)
10M
100M
V
S
= ±15V
T
A
= 25°C
INPUT VOLTAGE NOISE (nV/√Hz)
PHASE MARGIN (DEGREES)
80
–PSRR
60
+PSRR
0.1
40
0.01
100k
0
100
1k
10k
100k 1M
FREQUENCY (Hz)
10M
100M
LT1226 TPC11
LT1226 TPC12
Output Swing vs Settling Time
38
V
S
= ±15
T
A
= 25°C
10mV SETTLING
Frequency Response vs
Capacitive Load
36
34
32
30
28
26
24
22
20
18
C = 1000pF
C = 500pF
V
S
= ±15V
T
A
= 25°C
A
V
= –25
C = 100pF
C = 50pF
C = 0pF
40
20
A
V
= –25
A
V
= +25
0
100M
–10
0
20
60
80
40
SETTLING TIME (ns)
100
120
1M
10M
FREQUENCY (HZ)
100M
LT1226 TPC15
LTC1226 TPC14
Gain Bandwidth vs Temperature
1.15
V
S
= ±15V
1.10
450
400
500
Slew Rate vs Temperature
V
S
= ±15V
A
V
= –25
–SR
+SR
350
300
250
200
–50 –25
100M
0.85
–50 –25
50
25
75
0
TEMPERATURE (˚C)
100
125
50
25
75
0
TEMPERATURE (˚C)
100
125
LT1226 TPC17
LT1226 TPC18
5
