LINER LT1221 150mhz operational amplifier Datasheet

LT1221
150MHz, 250V/µs, AV ≥ 4
Operational Amplifier
U
DESCRIPTIO
FEATURES
■
■
■
■
■
■
■
■
■
■
■
■
■
■
Gain-Bandwidth: 150MHz
Gain of 4 Stable
Slew Rate: 250V/µs
Input Noise Voltage: 6nV/√Hz
C-LoadTM Op Amp Drives Capacitive Loads
Maximum Input Offset Voltage: 600µV
Maximum Input Bias Current: 300nA
Maximum Input Offset Current: 300nA
Minimum Output Swing Into 500Ω: ±12V
Minimum DC Gain: 50V/mV, RL = 500Ω
Settling Time to 0.1%: 65ns, 10V Step
Settling Time to 0.01%: 85ns, 10V Step
Differential Gain: 0.08%, AV = 4, RL = 150Ω
Differential Phase: 0.2°, AV = 4, RL = 150Ω
UO
APPLICATI
■
■
■
■
■
Wideband Amplifiers
Buffers
Active Filters
Video and RF Amplification
Cable Drivers
8-, 10-, 12-Bit Data Acquisition Systems
The LT1221 is a member of a family of fast, high performance amplifiers that employ Linear Technology
Corporation’s advanced complementary bipolar processing. For unity-gain stable applications the LT1220 can be
used, and for gains of 10 or greater the LT1222 can be used.
and LTC are registered trademarks and LT is a trademark of Linear Technology Corporation.
C-Load is a trademark of Linear Technology Cortporation.
U
■
S
The LT1221 is a very high speed operational amplifier with
superior DC performance. The LT1221 is stable in a noise
gain of 4 or greater. It features reduced input offset
voltage, lower input bias currents and higher DC gain than
devices with comparable bandwidth and slew rate. The
circuit is a single gain stage that includes proprietary DC
gain enhancement circuitry to obtain precision with high
speed. The high gain and fast settling time make the circuit
an ideal choice for data acquisition systems. The circuit is
also capable of driving capacitive loads which makes it
useful in buffer or cable driver applications.
TYPICAL APPLICATION
Summing Amplifier
1k
Summing Amplifier Large-Signal Response
1k
VA
VB
VC
1k
–
LT1221
1k
VOUT
+
LT1221 • TA01
VS = ±15V
VIN = 10VP-P
f = 2MHz
LT1221 • TA02
1
LT1221
W W
W
AXI U
U
ABSOLUTE
RATI GS
Total Supply Voltage (V + to V –) ............................. 36V
Differential Input Voltage ........................................ ±6V
Input Voltage .......................................................... ±VS
Output Short-Circuit Duration (Note 1) ........... Indefinite
Specified Temperature Range
LT1221C (Note 2) ................................... 0°C to 70°C
LT1221M ......................................... – 55°C to 125°C
Operating Temperature Range
LT1221C ........................................... – 40°C TO 85°C
LT1221M ......................................... – 55°C to 125°C
Maximum Junction Temperature (See Below)
Plastic Package ............................................... 150°C
Ceramic Package ............................................. 175°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
U
W
U
PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
TOP VIEW
NULL
8
NULL 1
6 VOUT
–IN 2
+IN 3
7 V+
5 NC
4
SPECIAL
ORDER
CONSULT
FACTORY
ORDER PART
NUMBER
TOP VIEW
NULL 1
8
NULL
–IN 2
7
V+
+IN 3
6
VOUT
V– 4
5
NC
J8 PACKAGE
8-LEAD CERAMIC DIP
–
V
H PACKAGE
8-LEAD TO-5 METAL CAN
N8 PACKAGE
8-LEAD PLASTIC DIP
S8 PACKAGE
8-LEAD PLASTIC SOIC
LT1221CN8
LT1221MJ8
LT1221CS8
S8 PART MARKING
1221
TJMAX = 175°C, θJA = 100°C/W (J)
TJMAX = 150°C, θJA = 130°C/W (N)
TJMAX = 150°C, θJA = 190°C/W (S)
TJMAX = 175°C, θJA = 150°C/W
Consult factory for Industrial grade parts.
ELECTRICAL CHARACTERISTICS
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
Inut Capacitance
Input Voltage Range (Positive)
Input Voltage Range (Negative)
Common-Mode Rejection Ratio
Power Supply Rejection Ratio
Large-Signal Voltage Gain
Output Swing
Output Current
Slew Rate
Full Power Bandwidth
Gain-Bandwidth
CMRR
PSRR
AVOL
VOUT
IOUT
SR
GBW
2
VS = ±15V, TA = 25°C, VCM = 0V, unless otherwise specified.
CONDITIONS
(Note 3)
f = 10kHz
f = 10kHz
VCM = ±12V
Differential
MIN
20
12
VCM = ±12V
VS = ±5V to ±15V
VOUT = ±10V, RL = 500Ω
RL = 500Ω
VOUT = ±12V
(Note 4)
10V Peak (Note 5)
f = 1MHz
92
90
50
12
24
200
TYP
200
100
100
6
2
45
80
2
14
– 13
114
110
100
13
26
250
4
150
MAX
600
300
300
– 12
UNITS
µV
nA
nA
nV/√Hz
pA/√Hz
MΩ
kΩ
pF
V
V
dB
dB
V/mV
±V
mA
V/µs
MHz
MHz
LT1221
ELECTRICAL CHARACTERISTICS
SYMBOL
tr, tf
ts
PARAMETER
Rise Time, Fall Time
Overshoot
Propagation Delay
Settling Time
Differential Gain
Differential Phase
RO
IS
Output Resistance
Supply Current
VS = ±15V, TA = 25°C, VCM = 0V, unless otherwise specified.
CONDITIONS
AV = 4, 10% to 90%, 0.1V
AV = 4, 0.1V
AV = 4, 50% VIN to 50% VOUT, 0.1V
10V Step, 0.1%
10V Step, 0.01%
f = 3.58MHz, RL = 150Ω (Note 6)
f = 3.58MHz, RL = 1k (Note 6)
f = 3.58MHz, RL = 150Ω (Note 6)
f = 3.58MHz, RL = 1k (Note 6)
AV = 4, f = 1MHz
MIN
TYP
3.2
10
5.4
65
85
0.08
0.02
0.20
0.05
0.3
8
MAX
TYP
0.2
15
100
100
114
110
100
13
26
250
8
MAX
1.5
TYP
0.2
15
100
100
114
110
100
13
13
26
13
250
8
MAX
2
10.5
UNITS
ns
%
ns
ns
ns
%
%
DEG
DEG
Ω
mA
VS = ±15V, 0°C ≤ TA ≤ 70°C, VCM = 0V, unless otherwise specified.
SYMBOL
VOS
IOS
IB
CMRR
PSRR
AVOL
VOUT
IOUT
SR
IS
PARAMETER
Input Offset Voltage
Input VOS Drift
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
(Note 3)
MIN
●
●
●
VCM = ±12V
VS = ±5V to ±15V
VOUT = ±10V, RL = 500Ω
RL = 500Ω
VOUT = ±12V
(Note 4)
●
●
●
●
●
●
92
90
40
12
24
180
●
400
400
11
UNITS
mV
µV/°C
nA
nA
dB
dB
V/mV
±V
mA
V/µs
mA
VS = ±15V, – 55°C ≤ TA ≤ 125°C, VCM = 0V, unless otherwise specified.
SYMBOL
VOS
IOS
IB
CMRR
PSRR
AVOL
VOUT
PARAMETER
Input Offset Voltage
Input VOS Drift
Input Offset Current
Input Bias Current
Common-Mode Rejection Ratio
Power Supply Rejection Ratio
Large-Signal Voltage Gain
Output Swing
IOUT
Output Current
SR
IS
Slew Rate
Supply Current
CONDITIONS
(Note 3)
MIN
●
●
●
VCM = ±12V
VS = ±5V to ±15V
VOUT = ±10V, RL = 500Ω
RL = 500Ω
RL = 1k
VOUT = ±10V
VOUT = ±12V
(Note 4)
The ● denotes specifications which apply over the full temperature range.
Note 1: A heat sink may be required when the output is shorted indefinitely.
Note 2: Commercial parts are designed to operate over – 40°C to 85°C, but
are not tested nor guaranteed beyond 0°C to 70°C. Industrial grade parts
specified and tested over – 40°C to 85°C are available on special request.
Consult factory.
●
●
●
●
●
●
●
●
●
92
90
12.5
10
12
20
12
130
800
1000
11
UNITS
mV
µV/°C
nA
nA
dB
dB
V/mV
±V
±V
mA
mA
V/µs
mA
Note 3: Input offset voltage is pulse tested and is exclusive of warm-up drift.
Note 4: Slew rate is measured between ±10V on an output swing of ±12V.
Note 5: FPBW = SR/2πVP.
Note 6: Differential Gain and Phase are tested in AV = 4 with five amps in
series. Attenuators of 1/4 are used as loads (36.5Ω, 110Ω and
249Ω, 750Ω).
3
LT1221
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Input Common-Mode Range
vs Supply Voltage
Supply Current vs Supply Voltage
and Temperature
20
10
15
+VCM
T = 125°C
10
–VCM
5
9
T = 25°C
8
7
6
0
T = –55°C
20
5
10
15
SUPPLY VOLTAGE (±V)
0
LT1221 • TPC01
15
+VSW
10
–VSW
5
5
10
15
SUPPLY VOLTAGE (±V)
0
20
LT1221 • TPC02
Output Voltage Swing
vs Resistive Load
500
TA = 25°C
∆VOS = 30mV
Open-Loop Gain
vs Resistive Load
20
±15V SUPPLIES
15
10
±5V SUPPLIES
5
110
TA = 25°C
VS = ±15V
TA = 25°C
100
300
200
OPEN-LOOP GAIN (dB)
INPUT BIAS CURRENT (nA)
400
20
LT1221 • TPC03
Input Bias Current
vs Input Common-Mode Voltage
30
25
TA = 25°C
RL = 500Ω
∆VOS = 30mV
0
5
5
10
15
SUPPLY VOLTAGE (±V)
0
OUTPUT VOLTAGE SWING (VP-P)
MAGNITUDE OF OUTPUT VOLATGE (V)
11
TA = 25°C
∆VOS = 0.5mV
SUPPLY CURRENT (mA)
MAGNITUDE OF INPUT VOLTAGE (V)
20
Output Voltage Swing
vs Supply Voltage
IB+
100
IB–
0
–100
–200
–300
VS = ±15V
90
VS = ±5V
80
70
– 400
0
100
1k
LOAD RESISTANCE (Ω)
– 500
–15
10k
60
0
5
–10
–5
10
INPUT COMMON-MODE VOLTAGE (V)
LT1221 • TPC04
LT1221 • TPC05
Output Short-Circuit Current
vs Temperature
INPUT NOISE VOLTAGE (nV/√Hz)
OUTPUT SHORT-CIRCUIT CURRENT (mA)
100
40
35
30
25
20
–50
VS = ±15V
TA = 25°C
AV = 101
RS = 100k
100
10
in
10
1
en
1
–25
50
0
25
75
TEMPERATURE (°C)
100
125
LT1221 • TPC07
10
100
1k
10k
FREQUENCY (Hz)
0.1
100k
LT1221 • TPC08
100
INPUT NOISE CURRENT (pA/√Hz)
45
4
Power Supply Rejection Ratio
vs Frequency
1000
VS = ±5V
10k
LT1221 • TPC06
Input Noise Spectral Density
50
100
1k
LOAD RESISTANCE (Ω)
10
15
POWER SUPPLY REJECTION RATIO (dB)
10
+PSRR
80
VS = ±15V
TA = 25°C
60
–PSRR
40
20
10
0
100
1k
10k 100k
1M
FREQUENCY (Hz)
10M
100M
LT1221 • TPC09
LT1221
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Common-Mode Rejection Ratio
vs Frequency
Output Swing and Error
vs Settling Time (Noninverting)
10
VS = ±15V
TA = 25°C
100
10
VS = ±15V
TA = 25°C
8
60
40
6
10mV
4
2
0
–2
–4
10mV
–6
20
0
10k
1M
100k
FREQUENCY (Hz)
10M
100M
1mV
75
100
50
SETTLING TIME (ns)
40
20
20
0
0
VOLTAGE MAGNITUDE (dB)
20
10k
1M
100k
FREQUENCY (Hz)
10M
–20
100M
VS = ±15V
TA = 25°C
AV = 4
C = 100pF
18
16
C = 50pF
14
12
10
1
0.01
0.001
10k
100
10
FREQUENCY (MHz)
170
SLEW RATE (V/µs)
300
150
140
130
VS = ±15V
AV = – 5
(SR+) + (SR –)
SR =
2
275
250
225
200
125
LT1221 • TPC16
1M
10M
FREQUENCY (Hz)
175
– 50 –25
0
25
50
75
TEMPERATURE (°C)
100M
Total Harmonic Distortion
vs Frequency
325
VS = ±15V
160
100k
LT1221 • TPC15
Slew Rate vs Temperature
180
100
0.1
LT1221 • TPC14
Gain-Bandwidth vs Temperature
0
75
25
50
TEMPERATURE (°C)
1
C = 1000pF
4
LT1221 • TPC13
120
– 50 – 25
C=0
C = 500pF
8
6
TA = 25°C
125
10
TOTAL HARMONIC DISTORTION AND NOISE (%)
VOLTAGE GAIN (dB)
VS = ±15V
PHASE MARGIN (DEG)
60
VS = ±5V
75
100
50
SETTLING TIME (ns)
Closed-Loop Output Impedance
vs Frequency
VS = ±15V
TA = 25°C
AV = – 5
22
80
VS = ±5V
25
0
1mV
LT1221 • TPC12
24
100
80
10mV
LT1220 • TPC11
VS = ±15V
1k
125
Frequency Response
vs Capacitive Load
100
–20
100
–4
–8
Voltage Gain and Phase
vs Frequency
40
–2
–10
LT1221 • TPC10
60
2
–8
25
1mV
0
–10
0
10mV
4
–6
OUTPUT IMPEDANCE (Ω)
1k
1mV
OUTPUT SWING (V)
80
VS = ±15V
TA = 25°C
8
6
OUTPUT SWING (V)
COMMON-MODE REJECTION RATIO (dB)
120
GAIN-BANDWIDTH (MHz)
Output Swing and Error
vs Settling Time (Inverting)
100
125
LT1221 • TPC19
0.01
VS = ±15V
VO = 3VRMS
RL = 500Ω
AV = 4
AV = –4
0.001
0.0001
10
100
1k
10k
FREQUENCY (Hz)
100k
LT1220 • TPC18
5
LT1221
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Small Signal, AV = 4
f = 5MHz
VS = ±15V
VIN = 5VP-P
LT1221 • TPC19
LT1221 • TPC20
f = 5MHz
VS = ±15V
VIN = 5VP-P
LT1221 • TPC22
f = 2MHz
VS = ±15V
VIN = 5VP-P
f = 20kHz
LT1221 • TPC21
Small Signal, AV = – 4,
CL = 1,000pF
Large Signal, AV = – 4
Small Signal, AV = – 4
U
W
VS = ±15V
VIN = 25mV
f = 2MHz
LT1221 • TPC23
VS = ±15V
VIN = 42mV
f = 500kHz
LT1221 • TPC24
U
VS = ±15V
VIN = 25mV
Large Signal, AV = 4,
CL = 10,000pF
Large Signal, AV = 4
U
APPLICATIONS INFORMATION
The LT1221 is stable in noise gains of 4 or greater and may
be inserted directly into HA2520/2/5, HA2541/2/4, AD817,
AD847, EL2020, EL2044 and LM6361 applications, provided that the nulling circuitry is removed and the amplifier configuration has a high enough noise gain. The
suggested nulling circuit for the LT1221 is shown in the
following figure.
Offset Nulling
V+
5k
1
3
+
0.1µF
8
7
LT1221
2
–
Input Considerations
0.1µF
6
The LT1221 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. Feedback resistors greater than 5k are not
recommended because a pole is formed with the input
capacitance which can cause peaking or oscillations.
6
4
V–
Layout and Passive Components
LT1221 • AI01
Bias current cancellation circuitry is employed on the
inputs of the LT1221 so the input bias current and input
LT1221
U
W
U
U
APPLICATIONS INFORMATION
offset current have identical specifications. For this reason,
matching the impedance on the inputs to reduce bias
current errors is not necessary.
Capacitive Loading
The LT1221 is stable with capacitive loads. 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. There will be peaking in the frequency domain as
shown in the curve of Frequency Response vs Capacitive
Load. The small-signal transient response will have more
overshoot as shown in the photo of the small-signal
response with 1000pF load. The large-signal response with
a 10,000pF load shows the output slew rate being limited
to 4V/µs by the short-circuit current. The LT1221 can drive
coaxial cable 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.
Compensation
The LT1221 has a typical gain-bandwidth product of
150MHz which allows it to have wide bandwidth in high
gain configurations (i.e., in a gain of 10, it will have a
bandwidth of about 15MHz). The amplifier is stable in a
noise gain of 4 so the ratio of the signal at the inverting input
to the output must be 1/4 or less. Straightforward gain
configurations of 4 or –3 are stable, but there are several
others that allow the amplifier to be stable for lower signal
gains (the noise gain, however, remains 4 or more). One
example is the summing amplifier on the first page of this
data sheet. Each input signal has a gain of –1 to the output,
but it is easily seen that this configuration is equivalent to
a gain of –3 as far as the amplifier is concerned. Another
circuit is shown below with a DC gain of 1, but an AC gain
of 5. The break frequency of the R-C combination across
the amplifier inputs should be approximately a factor of 10
less than the gain-bandwidth of the amplifier divided by the
high frequency gain (in this case 1/10 of 150MHz/5 or
3MHz).
U
TYPICAL APPLICATIONS N
Lag Compensation
20MHz, AV = 50 Instrumentation Amplifier
+
VIN
+
500Ω
+
VIN
100pF
2k
–
1k
1k
250Ω
200pF
1k
250Ω
VOUT
–
10k
LT1221
–
LT1221
1k
AV = 1, f < 3MHz
LT1221 • TA04
+
LT1221
VOUT
Cable Driver
–
10k
–
LT1221
LT1221 • TA03
VIN
+
75Ω
75Ω CABLE
LT1221
–
+
VOUT
75Ω
1.5k
510Ω
LT1221 • TA05
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.
7
LT1221
W
W
SI PLIFIED SCHE ATIC
V+ 7
NULL
1
8
BIAS 1
BIAS 2
6 OUT
2 –IN
+IN 3
V– 4
LT1221 • SS
U
PACKAGE DESCRIPTION
Dimensions in inches (millimeters) unless otherwise noted.
0.335 – 0.370
(8.509 – 9.398)
DIA
0.305 – 0.335
(7.747 – 8.509)
H8 Package
8-Lead TO-5
Metal Can
0.050
(1.270)
MAX
SEATING
PLANE
0.010 – 0.045
(0.254 – 1.143)
0.016 – 0.021
(0.406 – 0.533)
J8 Package
8-Lead Ceramic Dip
0.008 – 0.018
(0.203 – 0.457)
0.027 – 0.034
(0.686 – 0.864)
0.165 – 0.185
(4.191 – 4.699)
GAUGE
PLANE
0.300 BSC
(0.762 BSC)
0.200 – 0.230
(5.080 – 5.842)
BSC
REFERENCE
PLANE
0.500 – 0.750
(12.700 – 19.050)
0.200
(5.080)
MAX
0.385 ± 0.025
(9.779 ± 0.635)
0.023 – 0.045
(0.584 – 1.143)
HALF LEAD
OPTION
0.045 – 0.068
(1.143 – 1.727)
FULL LEAD
OPTION
0.300 – 0.325
(7.620 – 8.255)
N8 Package
8-Lead Plastic Dip
0.009 – 0.015
(0.229 – 0.381)
(
+0.025
0.325 –0.015
+0.635
8.255
–0.381
)
0.015 – 0.060
(0.381 – 1.524)
0.005
(0.127)
MIN
0.405
(10.287)
MAX
8
0.045 – 0.065
(1.143 – 1.651)
7
6
5
0.025
(0.635)
RAD TYP
0.220 – 0.310
(5.588 – 7.874)
1
0.045 – 0.068
(1.143 – 1.727)
0.014 – 0.026
(0.360 – 0.660)
NOTE: LEAD DIMENSIONS APPLY TO SOLDER
DIP/PLATE OR TIN PLATE LEADS.
0.110 – 0.160
(2.794 – 4.064)
INSULATING
STANDOFF
NOTE: LEAD DIAMETER IS UNCONTROLLED BETWEEN
THE REFERENCE PLANE AND SEATING PLANE.
CORNER LEADS OPTION
(4 PLCS)
0° – 15°
0.027 – 0.045
(0.686 – 1.143)
45°TYP
0.040
(1.016)
MAX
2
3
4
0.125
3.175
0.100 ± 0.010 MIN
(2.540 ± 0.254)
0.400*
(10.160)
MAX
0.130 ± 0.005
(3.302 ± 0.127)
0.065
(1.651)
TYP
8
7
6
5
0.255 ± 0.015*
(6.477 ± 0.381)
0.125
(3.175)
MIN
0.045 ± 0.015
(1.143 ± 0.381)
0.100 ± 0.010
(2.540 ± 0.254)
0.018 ± 0.003
(0.457 ± 0.076)
0.015
(0.380)
1
2
4
3
MIN
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR
PROTRUSIONS. MOLD FLASH OR PROTURSIONS SHALL
NOT EXCEED 0.010 INCH (0.254mm).
0.189 – 0.197*
(4.801 – 5.004)
0.010 – 0.020
× 45°
(0.254 – 0.508)
S8 Package
8-Lead Plastic SOIC
0.008 – 0.010
(0.203 – 0.254)
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)
8
0.050
(1.270)
BSC
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006 INCH (0.15mm).
8
Linear Technology Corporation
7
6
5
0.004 – 0.010
(0.101 – 0.254)
0.150 – 0.157*
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
1
2
3
4
LT/GP 0894 5K REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7487
(408) 432-1900 ● FAX: (408) 434-0507 ● TELEX: 499-3977
 LINEAR TECHNOLOGY CORPORATION 1992