LINER LT1254CS

LT1253/LT1254
Low Cost Dual and Quad
Video Amplifiers
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DESCRIPTIO
FEATURES
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Low Cost
Current Feedback Amplifiers
Differential Gain: 0.03%, RL = 150Ω, VS = ±5V
Differential Phase: 0.28°, RL = 150Ω, VS = ±5V
Flat to 30MHz, 0.1dB
90MHz Bandwidth on ±5V
Wide Supply Range: ±2V(4V) to ±14V(28V)
Low Power: 60mW per Amplifier at ±5V
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APPLICATI
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The LT1253 is a low cost dual current feedback amplifier
for video applications. The LT1254 is a quad version of the
LT1253. The amplifiers are completely isolated except for
the power supply pins and therefore have excellent isolation, over 94dB at 5MHz. Dual and quad amplifiers significantly reduce costs compared with singles; the number of
insertions is reduced and fewer supply bypass capacitors
are required. In addition, these duals and quads cost less
per amplifier than single video amplifiers.
The LT1253/LT1254 amplifiers are ideal for driving low
impedance loads such as cables and filters. The wide
bandwidth and high slew rate of these amplifiers make
driving RGB signals between PCs and workstations easy.
The excellent linearity of these amplifiers makes them
ideal for composite video.
RGB Cable Drivers
Composite Video Cable Drivers
Gain Blocks in IF Stages
The LT1253 is available in 8-pin DIPs and the S8 surface
mount package. The LT1254 is available in 14-pin DIPs
and the S14 surface mount package. Both parts have the
industry standard dual and quad op amp pin out. For
higher performance, see the LT1229/LT1230.
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TYPICAL APPLICATI
Transient Response
5V
VIN
+
75Ω
1/2 LT1253
–
–5V
75Ω
CABLE
RF
620Ω
VOUT
RG
620Ω
RF
BW = 90MHz
RG
AT AMPLIFIER OUTPUT.
6dB LESS AT VOUT.
75Ω
AV = 1 +
LT1253/54 • TA01
VS = ±5V
AV = 2
RL = 150Ω
VO = 1V
LT1253/54 • TA02
1
LT1253/LT1254
W W
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AXI U
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ABSOLUTE
RATI GS
Total Supply Voltage (V + to V –) ............................. 28V
Input Current ..................................................... ±15mA
Output Short-Circuit Duration (Note 1) ........ Continuous
Operating Temperature Range
LT1253C, LT1254C................................. 0°C to 70°C
Storage Temperature Range ................ – 65°C to 150°C
Junction Temperature (Note 2) ............................ 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
W
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PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
TOP VIEW
OUT A
1
8
V+
–IN A
2
7
OUT B
+IN A
3
6
–IN B
V–
4
5
+IN B
A
N8 PACKAGE
8-LEAD PLASTIC DIP
B
S8 PACKAGE
8-LEAD PLASTIC SOIC
TJMAX = 150°C, θJA = 100°C/ W (N)
TJMAX = 150°C, θJA = 150°C/ W (S)
TOP VIEW
OUT A
1
–IN A
2
+IN A
3
V+
4
LT1253CN8
LT1253CS8
S8 PART MARKING
+IN B
5
–IN B
6
OUT B
7
13 –IN D
A
D
12 +IN D
LT1254CN
LT1254CS
11 V –
10 +IN C
B
N PACKAGE
14-LEAD PLASTIC DIP
1253
ORDER PART
NUMBER
14 OUT D
C
9
–IN C
8
OUT C
S PACKAGE
14-LEAD PLASTIC SOIC
TJMAX = 150°C, θJA = 70°C/ W (N)
TJMAX = 150°C, θJA = 100°C/ W (S)
ELECTRICAL CHARACTERISTICS
0°C ≤ TA ≤ 70°C, VS = ±5V to ±12V, unless otherwise noted.
Symbol
Parameter
VOS
Input Offset Voltage
+IB
Noninverting Bias Current
– IB
Inverting Bias Current
AVOL
Large-Signal Voltage Gain
VS = ±5V, VO = ±2V, RL = 150Ω
PSRR
Power Supply Rejection Ratio
VS = ±3V to ±12V
60
70
dB
CMRR
Common-Mode Rejection Ratio
VS = ±5V, VCM = ±2V
55
65
dB
VOUT
Maximum Output Voltage Swing
VS = ±12V, RL = 500Ω
VS = ±5V, RL = 150Ω
±7.0
±2.5
±10.5
±3.7
V
V
IOUT
Maximum Output Current
IS
Supply Current
RIN
Input Resistance
CIN
Input Capacitance
Power Supply Range
SR
2
CONDITIONS
MIN
560
30
Per Amplifier
TYP
MAX
5
15
mV
1
15
µA
20
100
µA
1500
1
V/V
55
6
mA
11
10
mA
MΩ
3
±2
4
Dual
Single
UNITS
pF
±12
24
V
V
Channel Separation
f = 10MHz
88
dB
Input Slew Rate
AV = 1
125
V/µs
Output Slew Rate
AV = 2
250
V/µs
LT1253/LT1254
ELECTRICAL CHARACTERISTICS
0°C ≤ TA ≤ 70°C, VS = ±5V to ±12V, unless otherwise noted.
Symbol
Parameter
tr
Small-Signal Rise Time
VS = ±12V, AV = 2
3.5
ns
Rise and Fall Time
VS = ±5V, AV = 2, VOUT = 1VP-P
5.8
ns
Propagation Delay
VS = ±5V, AV = 2
3.5
ns
tp
CONDITIONS
Note 1: A heat sink may be required to keep the junction temperature
below absolute maximum when the output is shorted indefinitely.
Note 2: TJ is calculated from the ambient temperature TA and power
dissipation PD according to the following formulas:
MIN
TYP
MAX
UNITS
LT1253CN8: TJ = TA + (PD × 100°C/W)
LT1253CS8: TJ = TA + (PD × 150°C/W)
LT1254CN: TJ = TA + (PD × 70°C/W)
LT1254CS: TJ = TA + (PD × 100°C/W)
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TYPICAL AC PERFOR A CE
BANDWIDTH
VS
AV
RL
RF
RG
Small Signal
– 3dB BW (MHz)
Small Signal
– 0.1dB BW (MHz)
Small Signal
Peaking (dB)
±12
1
1000
1100
None
270
51
3.4
±12
1
150
1000
None
204
48
1.3
±12
–1
1000
750
150
110
59
0.1
±12
–1
150
768
768
89
50
0.1
±12
2
1000
715
715
179
76
0.3
±12
2
150
715
715
117
62
0
±12
5
1000
680
180
106
42
0
±12
5
150
680
180
90
47
0
±12
10
1000
620
68.1
89
49
0.1
±12
10
150
620
68.1
80
46
0.1
±5
1
1000
787
None
218
53
1.5
±5
1
150
787
None
158
91
0.1
±5
–1
1000
715
715
76
28
0.1
±5
–1
150
715
715
70
30
0.1
±5
2
1000
620
620
117
58
0.1
±5
2
150
620
620
92
52
0.1
±5
5
1000
620
150
82
36
0
±5
5
150
620
150
72
34
0
±5
10
1000
562
61.9
70
35
0
±5
10
150
562
61.9
65
28
0
NTSC VIDEO (Note 1)
VS
AV
RL
RF
RG
DIFFERENTIAL
GAIN
DIFFERENTIAL
PHASE
±12
2
1000
750
750
0.01%
0.03°
±12
2
150
750
750
0.01%
0.12°
±5
2
1000
750
750
0.03%
0.18°
±5
2
150
750
750
0.03%
0.28°
Note 1: Differential Gain and Phase are measured using a Tektronix TSG
120 YC/NTSC signal generator and a Tektronix 1780R Video Measurement
Set. The resolution of this equipment is 0.1% and 0.1°. Ten identical
amplifier stages were cascaded giving an effective resolution of 0.01% and
0.01°.
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LT1253/LT1254
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TYPICAL PERFOR A CE CHARACTERISTICS
Output Saturation Voltage
vs Temperature
Supply Current vs Supply Voltage
V+
–55°C
7
25°C
6
5
125°C
4
175°C
3
2
1
2
4
8 10 12 14
6
SUPPLY VOLTAGE (±V)
16
–1.0
RL = ∞
±2V ≤ VS ≤ ±12V
1.0
0.5
18
50
0
25
75
TEMPERATURE (°C)
Settling Time to 10mV
vs Output Step
100
6
DISTORTION (dBc)
4
2
VS = ±12V
RF = RG = 1k
–2
–4
–6
2ND
–40
3RD
–50
40
60
SETTLING TIME (ns)
80
100
10
FREQUENCY (MHz)
1
LT1253/54 • TPC04
40
NEGATIVE
20
10
en
1k
10k
FREQUENCY (Hz)
100k
LT1253/54 • TPC07
100M
70
10
1.0
RF = RG = 2k
RF = RG = 750Ω
0.1
0.01
+in
1M
10M
FREQUENCY (Hz)
Output Short-Circuit Current
vs Temperature
OUTPUT SHORT-CIRCUIT CURRENT (mA)
–in
100k
LT1253/54 • TPC06
100
OUTPUT IMPEDANCE (Ω)
SPOT NOISE (nV/√Hz OR pA/√Hz)
POSITIVE
0
10k
100
VS = ±12V
4
60
Output Impedance
vs Frequency
100
100
125
VS = ±12V
RL = 100Ω
RF = RG = 750Ω
LT1253/54 • TPC05
Spot Noise Voltage and Current
vs Frequency
1
10
100
LT1253/54 • TPC03
–70
20
0
25
50
75
TEMPERATURE (°C)
INVERTING
–10
0
1.0
Power Supply Rejection
vs Frequency
–60
NONINVERTING
V – = –2V TO –12V
1.5
80
VS = ±12V
VO = 2VP-P
RL = 100Ω
RF = 750Ω
AV = 10dB
INVERTING
–30
–8
2.0
V–
– 50 –25
125
–20
0
–2.0
2nd and 3rd Harmonic Distortion
vs Frequency
10
NONINVERTING
V + = 2V TO 12V
–1.5
LT1253/54 • TPC02
LT1253/54 • TPC01
8
–1.0
0.5
V–
–50 –25
0
0
– 0.5
–0.5
POWER SUPPLY REJECTION (dB)
SUPPLY CURRENT (mA)
8
OUTPUT SATURATION VOLTAGE (V)
9
V+
COMMON-MODE RANGE (V)
10
OUTPUT STEP (V)
Input Common-Mode Limit
vs Temperature
0.001
10k
100k
1M
10M
FREQUENCY (Hz)
100M
LT1253/54 • TPC08
60
50
40
30
–50 –25
0
25 50 75 100 125 150 175
TEMPERATURE (°C)
LT1253/54 • TPC09
LT1253/LT1254
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TYPICAL PERFOR A CE CHARACTERISTICS
±12V Frequency Response
±5V Frequency Response
4
3
PHASE
0
–20
4
–20
–40
3
–60
2
–80
GAIN
0
–100
–40
PHASE
–80
0
–100
GAIN
–1
–1
–120
–2
–140
–2
–160
–3
–180
–4
–200
–5
1M
–3
–4
–5
1M
VS = ±12V
AV = 1
RL = 150Ω
RF = 1k
10M
100M
FREQUENCY (Hz)
1G
–140
–160
–180
–200
10M
100M
FREQUENCY (Hz)
±5V Frequency Response
0
11
–20
11
–40
10
–60
9
10
PHASE
GAIN (dB)
–100
6
–120
4
3
2
1M
10M
100M
FREQUENCY (Hz)
–40
PHASE
–80
7
–100
6
–120
–160
4
–180
3
–200
2
1M
1G
VS = ±5V
AV = 2
RL = 150Ω
RF = 620Ω
RG = 620Ω
–140
GAIN
–160
–180
–200
10M
100M
FREQUENCY (Hz)
1G
LT1253/54 • TPC13
LT1253/54 • TPC12
±12V Frequency Response
±5V Frequency Response
26
0
26
0
25
–20
25
–20
PHASE
–40
24
–60
23
21
–100
20
19
18
17
16
1M
–120
VS = ±12V
AV = 10
RL = 150Ω
RF = 620Ω
RG = 68.1Ω
GAIN
10M
100M
FREQUENCY (Hz)
1G
LT1253/54 • TPC14
–40
PHASE
–60
22
–80
21
–100
20
–140
19
–160
18
–180
17
–200
16
1M
–120
VS = ±5V
AV = 10
RL = 150Ω
RF = 562Ω
RG = 61.9Ω
PHASE (DEG)
–80
PHASE (DEG)
22
GAIN (dB)
24
23
GAIN (dB)
–60
8
5
–140
GAIN
0
–20
PHASE (DEG)
–80
7
PHASE (DEG)
8
GAIN (dB)
12
12
VS = ±12V
AV = 2
RL = 150Ω
RF = 715Ω
RG = 715Ω
1G
LT1253/54 • TPC11
±12V Frequency Response
5
–120
VS = ±5V
AV = 1
RL = 150Ω
RF = 787Ω
LT1253/54 • TPC10
9
–60
1
PHASE (DEG)
1
5
PHASE (DEG)
GAIN (dB)
2
0
GAIN (dB)
5
–140
GAIN
10M
100M
FREQUENCY (Hz)
–160
–180
–200
1G
LT1253/54 • TPC15
5
LT1253/LT1254
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TYPICAL PERFOR A CE CHARACTERISTICS
Transient Response
Transient Response
VS = ±5V
AV = 1
RL = 150Ω
RF = 787Ω
VO = 1V
LT1253/54 • TPC16
RF = 562Ω
RG = 61.9Ω
VO = 1.5V
VS = ±5V
AV = 10
RL = 150Ω
LT1253/54 • TPC17
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APPLICATIO S I FOR ATIO
Power Dissipation
PDMAX = 2 × VS × ISMAX + (VS – VOMAX) × VOMAX/RL
The LT1253/LT1254 amplifiers combine high speed and
large output current drive into very small packages. Because these amplifiers work over a very wide supply range,
it is possible to exceed the maximum junction temperature
under certain conditions. To insure that the LT1253/
LT1254 are used properly, we must calculate the worst
case power dissipation, define the maximum ambient
temperature, select the appropriate package and then
calculate the maximum junction temperature.
PDMAX = 2 × 12V × 7mA + (12V – 2V) × 2V/150
The worst case amplifier power dissipation is the total of
the quiescent current times the total power supply voltage
plus the power in the IC due to the load. The quiescent
supply current of the LT1253/LT1254 has a strong negative temperature coefficient. The supply current of each
amplifier at 150°C is less than 7mA and typically is only
4.5mA. The power in the IC due to the load is a function of
the output voltage, the supply voltage and load resistance.
The worst case occurs when the output voltage is at half
supply, if it can go that far, or its maximum value if it
cannot reach half supply.
For example, let’s calculate the worst case power dissipation in a video cable driver operating on a ±12V supply that
delivers a maximum of 2V into 150Ω.
6
= 0.168 + 0.133 = 0.301 Watt per Amp
Now if that is the dual LT1253, the total power in the
package is twice that, or 0.602W. We now must calculate
how much the die temperature will rise above the ambient.
The total power dissipation times the thermal resistance of
the package gives the amount of temperature rise. For the
above example, if we use the S8 surface mount package,
the thermal resistance is 150°C/W junction to ambient in
still air.
Temperature Rise = PDMAX × RθJA = 0.602W
× 150°C/W = 90.3°C
The maximum junction temperature allowed in the plastic
package is 150°C. Therefore the maximum ambient allowed is the maximum junction temperature less the
temperature rise.
Maximum Ambient = 150°C – 90.3°C = 59.7°C
Note that this is less than the maximum of 70°C that is
specified in the absolute maximum data listing. In order to
use this package at the maximum ambient we must lower
the supply voltage or reduce the output swing.
LT1253/LT1254
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APPLICATIO S I FOR ATIO
As a guideline to help in the selection of the LT1253/
LT1254, the following table describes the maximum supply voltage that can be used with each part based on the
following assumptions:
MAX POWER
at MAX TA
1. The maximum ambient is 70°C.
2. The load is a double-terminated video cable, 150Ω.
3. The maximum output voltage is 2V (peak or DC).
LT1253CN8
VS < ±14 (Abs Max)
0.800W
LT1253CS8
VS < ±10.6
0.533W
LT1254CN
VS < ±11.4
1.143W
LT1254CS
VS < ±7.6
0.727W
W
W
SI PLIFIED SCHE ATIC
One Amplifier
V+
–IN
+IN
VOUT
V–
LT1253/54 • SS
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PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
N8 Package
8-Lead Plastic DIP
0.300 – 0.320
(7.620 – 8.128)
0.009 – 0.015
(0.229 – 0.381)
(
+0.025
0.325 –0.015
+0.635
8.255
–0.381
)
0.045 – 0.065
(1.143 – 1.651)
0.130 ± 0.005
(3.302 ± 0.127)
0.400
(10.160)
MAX
8
7
6
5
0.065
(1.651)
TYP
0.045 ± 0.015
(1.143 ± 0.381)
0.100 ± 0.010
(2.540 ± 0.254)
0.250 ± 0.010
(6.350 ± 0.254)
0.125
(3.175)
MIN
0.020
(0.508)
MIN
1
2
3
0.018 ± 0.003
(0.457 ± 0.076)
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.
4
N8 0392
7
LT1253/LT1254
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PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
N Package
14-Lead Plastic DIP
0.300 – 0.325
(7.620 – 8.255)
0.045 – 0.065
(1.143 – 1.651)
0.015
(0.380)
MIN 0.130 ± 0.005
(3.302 ± 0.127)
0.770
(19.558)
MAX
0.065
(1.651)
TYP
(
+0.635
8.255
–0.381
)
13
12
11
10
9
8
1
2
3
4
5
6
7
0.260 ± 0.010
(6.604 ± 0.254)
0.009 – 0.015
(0.229 – 0.381)
+0.025
0.325 –0.015
14
0.075 ± 0.015
(1.905 ± 0.381)
0.018 ± 0.003
(0.457 ± 0.076)
0.125
(3.175)
MIN
0.100 ± 0.010
(2.540 ± 0.254)
N14 0392
S8 Package
8-Lead SOIC
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)
0.016 – 0.050
0.406 – 1.270
0°– 8° TYP
7
6
5
0.004 – 0.010
(0.101 – 0.254)
0.014 – 0.019
(0.355 – 0.483)
0.050
(1.270)
BSC
0.228 – 0.244
(5.791 – 6.197)
0.150 – 0.157
(3.810 – 3.988)
1
2
3
4
SO8 0392
S Package
14-Lead SOIC
0.337 – 0.344
(8.560 – 8.738)
0.010 – 0.020
× 45°
(0.254 – 0.508)
14
0.053 – 0.069
(1.346 – 1.752)
0.008 – 0.010
(0.203 – 0.254)
0° – 8° TYP
0.016 – 0.050
0.406 – 1.270
0.014 – 0.019
(0.355 – 0.483)
0.050
(1.270)
TYP
12
11
10
9
8
0.228 – 0.244
(5.791 – 6.197)
0.150 – 0.157
(3.810 – 3.988)
1
8
13
0.004 – 0.010
(0.101 – 0.254)
Linear Technology Corporation
2
3
4
5
6
7
SO14 0392
LT/GP 0193 10K REV 0
1630 McCarthy Blvd., Milpitas, CA 95035-7487
(408) 432-1900 ● FAX: (408) 434-0507 ● TELEX: 499-3977
 LINEAR TECHNOLOGY CORPORATION 1993