1
LT1468
90MHz, 22V/
s
16-Bit Accurate
Operational Amplifier
FREQUENCY (Hz)
100
110
TOTAL HARMONIC DISTORTION (dB)
100
90
1k
10k
100k
1468 TA02
120
130
80
V
S
=
15V
A
V
= 2
R
L
= 2k
V
OUT
= 10V
P-P
Total Harmonic Distortion vs Frequency
FEATURES
DESCRIPTIO
U
The LT
1468 is a precision high speed operational ampli-
fier with 16-bit accuracy and 900ns settling to 150
V for
10V signals. This unique blend of precision and AC perfor-
mance makes the LT1468 the optimum choice for high
accuracy applications such as DAC current-to-voltage
conversion and ADC buffers. The initial accuracy and drift
characteristics of the input offset voltage and inverting
input bias current are tailored for inverting applications.
The 90MHz gain bandwidth ensures high open-loop gain
at frequency for reducing distortion. In noninverting appli-
cations such as an ADC buffer, the low distortion and DC
accuracy allow full 16-bit AC and DC performance.
The 22V/
s slew rate of the LT1468 improves large-signal
performance in applications such as active filters and
instrumentation amplifiers compared to other precision
op amps.
The LT1468 is manufactured on Linear Technology's
complementary bipolar process.
s
90MHz Gain Bandwidth, f = 100kHz
s
22V/
s Slew Rate
s
Settling Time: 900ns (A
V
= 1, 150
V, 10V Step)
s
Low Distortion, 96.5dB for 100kHz, 10V
P-P
s
Maximum Input Offset Voltage: 75
V
s
Maximum Input Offset Voltage Drift: 2
V/
C
s
Maximum () Input Bias Current: 10nA
s
Minimum DC Gain: 1000V/mV
s
Minimum Output Swing into 2k:
12.8V
s
Unity Gain Stable
s
Input Noise Voltage: 5nV/
Hz
s
Input Noise Current: 0.6pA/
Hz
s
Total Input Noise Optimized for 1k < R
S
< 20k
s
Specified at
5V and
15V
, LTC and LT are registered trademarks of Linear Technology Corporation.
s
16-Bit DAC Current-to-Voltage Converter
s
Precision Instrumentation
s
ADC Buffer
s
Low Distortion Active Filters
s
High Accuracy Data Acquisition Systems
s
Photodiode Amplifiers
APPLICATIO
N
S
U
TYPICAL APPLICATIO
U
20pF
6k
LTC
1597
LT1468
16
DAC
INPUTS
+
OFFSET: V
OS
+ I
B
(6k
) < 1LSB
SETTLING TIME TO 150
V = 1.7
s
SETTLING LIMITED BY 6k AND 20pF TO COMPENSATE DAC OUTPUT CAPACITANCE
V
OUT
2k
50pF
OPTIONAL NOISE FILTER
1468 TA01
16-Bit DAC I-to-V Converter
2
LT1468
(Note 1)
Total Supply Voltage (V
+
to V
) ............................... 36V
Maximum Input Current (Note 2) ......................... 10mA
Output Short-Circuit Duration (Note 3) ............ Indefinite
Operating Temperature Range ................ 40
C to 85
C
Specified Temperature Range (Note 4) ... 40
C to 85
C
Junction Temperature ........................................... 150
C
Storage Temperature Range ................. 65
C to 150
C
Lead Temperature (Soldering, 10 sec).................. 300
C
PACKAGE/ORDER I FOR ATIO
U
U
W
ABSOLUTE AXI U
RATI GS
W
W
W
U
ORDER PART
NUMBER
LT1468CN8
LT1468CS8
LT1468IN8
LT1468IS8
S8 PART MARKING
1468
1468I
Consult factory for Military Grade parts.
T
JMAX
= 150
C,
JA
= 130
C/W (N8)
T
JMAX
= 150
C,
JA
= 190
C/W (S8)
1
2
3
4
8
7
6
5
TOP VIEW
*DO NOT CONNECT
S8 PACKAGE
8-LEAD PLASTIC SO
N8 PACKAGE
8-LEAD PDIP
NULL
IN
+ IN
V
DNC*
V
+
V
OUT
NULL
ELECTRICAL CHARACTERISTICS
SYMBOL
PARAMETER
CONDITIONS
V
SUPPLY
MIN
TYP
MAX
UNITS
V
OS
Input Offset Voltage
15V
30
75
V
5V
50
175
V
I
OS
Input Offset Current
5V to
15V
13
50
nA
I
B
Inverting Input Bias Current
5V to
15V
3
10
nA
I
B
+
Noninverting Input Bias Current
5V to
15V
10
40
nA
Input Noise Voltage
0.1Hz to 10Hz
5V to
15V
0.3
V
P-P
e
n
Input Noise Voltage
f = 10kHz
5V to
15V
5
nV/
Hz
i
n
Input Noise Current
f = 10kHz
5V to
15V
0.6
pA/
Hz
R
IN
Input Resistance
V
CM
=
12.5V
15V
100
240
M
Differential
15V
50
150
k
C
IN
Input Capacitance
15V
4
pF
Input Voltage Range +
15V
12.5
13.5
V
5V
2.5
3.5
V
Input Voltage Range
15V
14.3
12.5
V
5V
4.3
2.5
V
CMRR
Common Mode Rejection Ratio
V
CM
=
12.5V
15V
96
110
dB
V
CM
=
2.5V
5V
96
112
dB
PSRR
Power Supply Rejection Ratio
V
S
=
4.5V to
15V
100
112
dB
A
VOL
Large-Signal Voltage Gain
V
OUT
=
12.5V, R
L
= 10k
15V
1000
9000
V/mV
V
OUT
=
12.5V, R
L
= 2k
15V
500
5000
V/mV
V
OUT
=
2.5V, R
L
= 10k
5V
1000
6000
V/mV
V
OUT
=
2.5V, R
L
= 2k
5V
500
3000
V/mV
V
OUT
Output Swing
R
L
= 10k, V
IN
=
1mV
15V
13.0
13.6
V
R
L
= 2k, V
IN
=
1mV
15V
12.8
13.5
V
R
L
= 10k, V
IN
=
1mV
5V
3.0
3.6
V
R
L
= 2k, V
IN
=
1mV
5V
2.8
3.5
V
I
OUT
Output Current
V
OUT
=
12.5V
15V
15
22
mA
V
OUT
=
2.5V
5V
15
22
mA
I
SC
Short-Circuit Current
V
OUT
= 0V, V
IN
=
0.2V
15V
25
40
mA
T
A
= 25
C, V
CM
= 0V unless otherwise noted.
3
LT1468
SYMBOL
PARAMETER
CONDITIONS
V
SUPPLY
MIN
TYP
MAX
UNITS
SR
Slew Rate
A
V
= 1, R
L
= 2k (Note 5)
15V
15
22
V/
s
5V
11
17
V/
s
Full-Power Bandwidth
10V Peak, (Note 6)
15V
350
kHz
3V Peak, (Note 6)
5V
900
kHz
GBW
Gain Bandwidth
f = 100kHz, R
L
= 2k
15V
60
90
MHz
5V
55
88
MHz
THD
Total Harmonic Distortion
A
V
= 2, V
O
= 10V
P-P
, f = 1kHz
15V
0.00007
%
A
V
= 2, V
O
= 10V
P-P
, f = 100kHz
15V
0.0015
%
t
r
, t
f
Rise Time, Fall Time
A
V
= 1, 10% to 90%, 0.1V
15V
11
ns
5V
12
ns
Overshoot
A
V
= 1, 0.1V
15V
30
%
5V
35
%
Propagation Delay
A
V
= 1, 50% V
IN
to 50% V
OUT
, 0.1V
15V
9
ns
5V
10
ns
t
s
Settling Time
10V Step, 0.01%, A
V
= 1
15V
760
ns
10V Step, 150
V, A
V
= 1
15V
900
ns
5V Step, 0.01%, A
V
= 1
5V
770
ns
R
O
Output Resistance
A
V
= 1, f = 100kHz
15V
0.02
I
S
Supply Current
15V
3.9
5.2
mA
5V
3.6
5.0
mA
ELECTRICAL CHARACTERISTICS
T
A
= 25
C, V
CM
= 0V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
V
SUPPLY
MIN
TYP
MAX
UNITS
V
OS
Input Offset Voltage
15V
q
150
V
5V
q
250
V
Input V
OS
Drift
(Note 7)
5V to
15V
q
0.7
2.0
V/
C
I
OS
Input Offset Current
5V to
15V
q
65
nA
Input Offset Current Drift
5V to
15V
60
pA/
C
I
B
Inverting Input Bias Current
5V to
15V
q
15
nA
Negative Input Current Drift
5V to
15V
40
pA/
C
I
B
+
Noninverting Input Bias Current
5V to
15V
q
50
nA
CMRR
Common Mode Rejection Ratio
V
CM
=
12.5V
15V
q
94
dB
V
CM
=
2.5V
5V
q
94
dB
PSRR
Power Supply Rejection Ratio
V
S
=
4.5V to
15V
q
98
dB
A
VOL
Large-Signal Voltage Gain
V
OUT
=
12.5V, R
L
= 10k
15V
q
500
V/mV
V
OUT
=
12.5V, R
L
= 2k
15V
q
250
V/mV
V
OUT
=
2.5V, R
L
= 10k
5V
q
500
V/mV
V
OUT
=
2.5V, R
L
= 2k
5V
q
250
V/mV
V
OUT
Output Swing
R
L
= 10k, V
IN
=
1mV
15V
q
12.9
V
R
L
= 2k, V
IN
=
1mV
15V
q
12.7
V
R
L
= 10k, V
IN
=
1mV
5V
q
2.9
V
R
L
= 2k, V
IN
=
1mV
5V
q
2.7
V
I
OUT
Output Current
V
OUT
=
12.5V
15V
q
12.5
mA
V
OUT
=
2.5V
5V
q
12.5
mA
I
SC
Short-Circuit Current
V
OUT
= 0V, V
IN
=
0.2V
15V
q
17
mA
SR
Slew Rate
A
V
= 1, R
L
= 2k (Note 5)
15V
q
13
V/
s
5V
q
9
V/
s
0
C
T
A
70
C, V
CM
= 0V unless otherwise noted.
4
LT1468
ELECTRICAL CHARACTERISTICS
0
C
T
A
70
C, V
CM
= 0V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
V
SUPPLY
MIN
TYP
MAX
UNITS
V
OS
Input Offset Voltage
15V
q
230
V
5V
q
330
V
Input V
OS
Drift
(Note 7)
5V to
15V
q
0.7
2.5
V/
C
I
OS
Input Offset Current
5V to
15V
q
80
nA
Input Offset Current Drift
5V to
15V
120
pA/
C
I
B
Inverting Input Bias Current
5V to
15V
q
30
nA
Negative Input Current Drift
5V to
15V
80
pA/
C
I
B
+
Noninverting Input Bias Current
5V to
15V
q
60
nA
CMRR
Common Mode Rejection Ratio
V
CM
=
12.5V
15V
q
92
dB
V
CM
=
2.5V
5V
q
92
dB
PSRR
Power Supply Rejection Ratio
V
S
=
4.5V to
15V
q
96
dB
A
VOL
Large-Signal Voltage Gain
V
OUT
=
12V, R
L
= 10k
15V
q
300
V/mV
V
OUT
=
10V, R
L
= 2k
15V
q
150
V/mV
V
OUT
=
2.5V, R
L
= 10k
5V
q
300
V/mV
V
OUT
=
2.5V, R
L
= 2k
5V
q
150
V/mV
V
OUT
Output Swing
R
L
= 10k, V
IN
=
1mV
15V
q
12.8
V
R
L
= 2k, V
IN
=
1mV
15V
q
12.6
V
R
L
= 10k, V
IN
=
1mV
5V
q
2.8
V
R
L
= 2k, V
IN
=
1mV
5V
q
2.6
V
I
OUT
Output Current
V
OUT
=
12.5V
15V
q
7
mA
V
OUT
=
2.5V
5V
q
7
mA
I
SC
Short-Circuit Current
V
OUT
= 0V, V
IN
=
0.2V
15V
q
12
mA
SR
Slew Rate
A
V
= 1, R
L
= 2k (Note 5)
15V
q
9
V/
s
5V
q
6
V/
s
GBW
Gain Bandwidth
f = 100kHz, R
L
= 2k
15V
q
45
MHz
5V
q
40
MHz
I
S
Supply Current
15V
q
7.0
mA
5V
q
6.8
mA
40
C
T
A
85
C, V
CM
= 0V unless otherwise noted (Note 4).
SYMBOL
PARAMETER
CONDITIONS
V
SUPPLY
MIN
TYP
MAX
UNITS
GBW
Gain Bandwidth
f = 100kHz, R
L
= 2k
15V
q
55
MHz
5V
q
50
MHz
I
S
Supply Current
15V
q
6.5
mA
5V
q
6.3
mA
The
q
denotes specifications that apply over the full operating
temperature range.
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The inputs are protected by back-to-back diodes and two 100
series resistors. If the differential input voltage exceeds 0.7V, the input
current should be limited to 10mA. Input voltages outside the supplies will
be clamped by ESD protection devices and input currents should also be
limited to 10mA.
Note 3: A heat sink may be required to keep the junction temperature
below absolute maximum when the output is shorted indefinitely.
Note 4: The LT1468C 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 at 85
C. The
LT1468I is guaranteed to meet the extended temperature limits.
Note 5: Slew rate is measured between
8V on the output with
12V input
for
15V supplies and
2V on the output with
3V input for
5V supplies.
Note 6: Full power bandwidth is calculated from the slew rate
measurement: FPBW = SR/2
V
P
Note 7: This parameter is not 100% tested.
5
LT1468
TYPICAL PERFOR A CE CHARACTERISTICS
U
W
INPUT COMMON MODE VOLTAGE (V)
15
INPUT BIAS CURRENT (nA)
20
0
20
0
10
1468 G03
40
60
80
10
5
5
40
I
B
I
B
+
60
80
15
V
S
=
15V
T
A
= 25
C
Input Bias Current
vs Input Common Mode Voltage
TEMPERATURE (
C)
50
0
10
I
B
I
B
+
30
25
75
1468 G04
10
20
25
0
50
100
125
30
40
20
INPUT BIAS CURRENT (nA)
V
S
=
15V
Input Bias Current
vs Temperature
SUPPLY VOLTAGE (
V)
0
1
SUPPLY CURRENT (mA)
2
3
4
5
6
125
C
25
C
55
C
7
5
10
15
20
1468 G01
Supply Current vs Supply Voltage
and Temperature
SUPPLY VOLTAGE (
V)
0
V
COMMON MODE RANGE (V)
1.0
2.0
2.0
3
6
9
12
1468 G02
15
1.0
0.5
1.5
1.5
V
+
0.5
18
T
A
= 25
C
V
OS
< 100
V
Input Common Mode Range
vs Supply Voltage
0.1Hz to 10Hz Voltage Noise
TIME (1s/DIV)
VOLTAGE NOISE (100nV/DIV)
1468 G06
V
S
=
15V
Input Noise Spectral Density
FREQUENCY (Hz)
1
1
INPUT VOLTAGE NOISE (nV/
Hz)
INPUT CURRENT NOISE (pA/
Hz)
100
1000
10
100
1k
10k
100k
1468 G05
10
0.01
1
i
n
e
n
10
0.1
V
S
=
15V
T
A
= 25
C
A
V
= 101
R
S
= 100k FOR i
n
Warm-Up Drift vs Time
TIME AFTER POWER UP (s)
0
20
40
60
80
100
120
140
40
OFFSET VOLTAGE DRIFT (
V)
35
25
20
15
5
1468 G07
30
10
5
0
S0-8
15V
N8
5V
S0-8
5V
N8
15V
LOAD RESISTANCE (
)
10
110
OPEN-LOOP GAIN (dB)
130
135
140
100
1k
10k
1468 G08
125
120
115
T
A
= 25
C
V
S
=
15V
V
S
=
5V
Open-Loop Gain
vs Resistive Load
Open-Loop Gain
vs Temperature
TEMPERATURE (
C)
50
130
140
160
25
75
1468 G09
120
110
25
0
50
100
125
100
90
150
OPEN-LOOP GAIN (dB)
R
L
= 2k
V
S
=
15V
V
S
=
5V
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