LT1229CJ8 [Linear]
Dual and Quad 100MHz Current Feedback Amplifiers; 双路和四路100MHz的电流反馈放大器型号: | LT1229CJ8 |
厂家: | Linear |
描述: | Dual and Quad 100MHz Current Feedback Amplifiers |
文件: | 总12页 (文件大小:293K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
LT1229/LT1230
Dual and Quad 100MHz
Current Feedback Amplifiers
U
DESCRIPTIO
EATURE
S
F
■
■
■
■
■
■
■
■
■
■
■
100MHz Bandwidth
1000V/µs Slew Rate
Low Cost
The LT1229/LT1230 dual and quad 100MHz current feed-
back amplifiers are designed for maximum performance
in small packages. Using industry standard pinouts, the
dual is available in the 8-pin miniDIP and the 8-pin SO
package while the quad is in the 14-pin DIP and 14-pin SO.
The amplifiers are designed to operate on almost any
available supply voltage from 4V (±2V) to 30V (±15V).
30mA Output Drive Current
0.04% Differential Gain
0.1° Differential Phase
High Input Impedance: 25MΩ, 3pF
Wide Supply Range: ±2V to ±15V
Low Supply Current: 6mA Per Amplifier
Inputs Common Mode to Within 1.5V of Supplies
Outputs Swing Within 0.8V of Supplies
These current feedback amplifiers have very high input
impedance and make excellent buffer amplifiers. They
maintain their wide bandwidth for almost all closed-loop
voltage gains. The amplifiers drive over 30mA of output
current and are optimized to drive low impedance loads,
such as cables, with excellent linearity at high frequencies.
O U
PPLICATI
S
A
■
■
■
■
Video Instrumentation Amplifiers
Cable Drivers
The LT1229/LT1230 are manufactured on Linear
Technology’sproprietarycomplementarybipolarprocess.
For a single amplifier like these see the LT1227 and for
better DC accuracy see the LT1223.
RGB Amplifiers
Test Equipment Amplifiers
U
O
TYPICAL APPLICATI
Loop Through Amplifier Frequency
Response
Video Loop Through Amplifier
10
R
187Ω
R
3.01k
R
750Ω
R
F2
750Ω
G2
G1
F1
0
NORMAL SIGNAL
–10
–20
–30
–
–
1/2
LT1229
1/2
LT1229
V
OUT
V
+
IN
V
–
3.01k
3.01k
IN
+
+
–40
1% RESISTORS
WORST CASE CMRR = 22dB
TYPICALLY = 38dB
COMMON-MODE SIGNAL
12.1k
12.1k
–50
–60
V
R
= G (V
+
– V
F2
–
)
IN
OUT
IN
10 100
1k 10k 100k 1M 10M 100M
= R
F1
F2
BNC INPUTS
R
= (G – 1) R
FREQUENCY (Hz)
G1
LT1229 • TA02
R
G – 1
HIGH INPUT RESISTANCE DOES NOT LOAD CABLE EVEN
WHEN POWER IS OFF
F2
R
=
G2
TRIM CMRR WITH R
G1
LT1229 • TA01
1
LT1229/LT1230
W W W
U
ABSOLUTE AXI U RATI GS
Supply Voltage ...................................................... ±18V
Input Current ...................................................... ±15mA
Output Short Circuit Duration (Note 1) .........Continuous
Operating Temperature Range
Storage Temperature Range ................. –65°C to 150°C
Junction Temperature
Plastic Package .............................................. 150°C
Ceramic Package ............................................ 175°C
Lead Temperature (Soldering, 10 sec.)................. 300°C
LT1229C, LT1230C ............................... 0°C to 70°C
LT1229M, LT1230M....................... –55°C to 125°C
W
U
/O
PACKAGE RDER I FOR ATIO
TOP VIEW
ORDER PART
NUMBER
ORDER PART
OUT A
–IN A
+IN A
1
2
3
4
5
6
7
14 OUT D
13 –IN D
NUMBER
TOP VIEW
+
D
C
A
B
OUT A
–IN A
+IN A
1
2
3
4
8
7
6
5
V
12
11
10
9
+IN D
LT1229MJ8
LT1229CJ8
LT1229CN8
LT1229CS8
LT1230MJ
LT1230CJ
LT1230CN
LT1230CS
OUT B
–
+
V
V
A
–IN B
+IN B
+IN B
–IN B
+IN C
–IN C
OUT C
B
–
V
J8 PACKAGE
N8 PACKAGE
OUT B
8
8-LEAD CERAMIC DIP 8-LEAD PLASTIC DIP
S8 PACKAGE
S8 PART MARKING
1229
J PACKAGE
N PACKAGE
8-LEAD PLASTIC SOIC
LT1124 • POI01
14-LEAD CERAMIC DIP 14-LEAD PLASTIC DIP
S PACKAGE
TJ MAX = 175°C, θJA = 100°C/W (J8)
14-LEAD PLASTIC SOIC LT1229 • POI02
TJ MAX = 175°C, θJA = 80°C/W (J)
T
J MAX = 150°C, θJA = 100°C/W (N8)
TJ MAX = 150°C, θJA = 150°C/W (S8)
T
T
J MAX = 150°C, θJA = 70°C/W (N)
J MAX = 150°C, θJA = 110°C/W (S)
ELECTRICAL CHARACTERISTICS
Each Amplifier, VCM = 0V, ±5V ≤ VS = ±15V, pulse tested unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
T = 25°C
MIN
TYP
MAX
UNITS
V
OS
Input Offset Voltage
±3
±10
±15
mV
mV
A
●
●
Input Offset Voltage Drift
Noninverting Input Current
10
µV/°C
+
I
I
T = 25°C
A
±0.3
±3
±10
µA
µA
IN
●
●
–
Inverting Input Current
T = 25°C
A
±10
±50
±100
µA
µA
IN
e
Input Noise Voltage Density
f = 1kHz, R = 1k, R = 10Ω, R = 0Ω
3.2
1.4
32
nV/√Hz
pA/√Hz
pA/√Hz
n
F
G
S
+i
Noninverting Input Noise Current Density
Inverting Input Noise Current Density
Input Resistance
f = 1kHz, R = 1k, R = 10Ω, R = 10k
F G S
n
–in
f = 1kHz
R
V
V
= ±13V, V = ±15V
●
●
2
2
25
25
MΩ
MΩ
IN
IN
IN
S
= ±3V, V = ±5V
S
C
IN
Input Capacitance
3
pF
Input Voltage Range
V = ±15V, T = 25°C
±13
±12
±3
±13.5
V
V
V
V
S
A
●
●
V = ±5V, T = 25°C
±3.5
S
A
±2
CMRR
Common-Mode Rejection Ratio
V = ±15V, V = ±13V, T = 25°C
55
55
55
55
69
69
dB
dB
dB
dB
S
CM
A
V = ±15V, V = ±12V
●
●
S
CM
V = ±5V, V = ±3V, T = 25°C
S
CM
A
V = ±5V, V = ±2V
S
CM
2
LT1229/LT1230
ELECTRICAL CHARACTERISTICS
Each Amplifier, VCM = 0V, ±5V ≤ VS = ±15V, pulse tested unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
V = ±15V, V = ±13V, T = 25°C
MIN
TYP
MAX
UNITS
Inverting Input Current
Common-Mode Rejection
2.5
10
10
10
10
µA/V
µA/V
µA/V
µA/V
S
CM
A
V = ±15V, V = ±12V
●
●
S
CM
V = ±5V, V = ±3V, T = 25°C
2.5
80
S
CM
A
V = ±5V, V = ±2V
S
CM
PSRR
Power Supply Rejection Ratio
V = ±2V to ±15V, T = 25°C
60
60
dB
dB
S
A
V = ±3V to ±15V
S
●
●
●
Noninverting Input Current
Power Supply Rejection
V = ±2V to ±15V, T = 25°C
10
50
50
nA/V
nA/V
S
A
V = ±3V to ±15V
S
Inverting Input Current
Power Supply Rejection
V = ±2V to ±15V, T = 25°C
0.1
5
5
µA/V
µA/V
S
A
V = ±3V to ±15V
S
A
V
Large-Signal Voltage Gain, (Note 2)
V = ±15V, V
= ±10V, R = 1k
●
●
55
55
65
65
dB
dB
S
OUT
L
V = ±5V, V
= ±2V, R = 150Ω
S
OUT
L
R
OL
Transresistance, ∆V /∆I , (Note 2)
V = ±15V, V
= ±10V, R = 1k
●
●
100
100
200
200
kΩ
kΩ
OUT IN–
S
OUT
L
V = ±5V, V
= ±2V, R = 150Ω
S
OUT
L
V
OUT
Maximum Output Voltage Swing, (Note 2) V = ±15V, R = 400Ω, T = 25°C
±12
±10
±3
±13.5
V
V
V
V
S
L
A
●
●
V = ±5V, R = 150Ω, T = 25°C
±3.7
S
L
A
±2.5
I
I
Maximum Output Current
Supply Current, (Note 3)
R = 0Ω, T = 25°C
30
65
6
125
mA
OUT
S
L
A
V
= 0V, Each Amplifier, T = 25°C
9.5
11
mA
mA
OUT
A
●
SR
SR
Slew Rate, (Notes 4 and 6)
Slew Rate
T = 25°C
300
700
2500
10
V/µs
V/µs
ns
A
V = ±15V, R = 750Ω, R = 750Ω, R = 400Ω
S
F
G
L
t
Rise Time, (Notes 5 and 6)
Small-Signal Bandwidth
Small-Signal Rise Time
Propagation Delay
T = 25°C
A
20
r
BW
V = ±15V, R = 750Ω, R = 750Ω, R = 100Ω
S
100
3.5
MHz
ns
F
G
L
t
V = ±15V, R = 750Ω, R = 750Ω, R = 100Ω
S F G L
r
V = ±15V, R = 750Ω, R = 750Ω, R = 100Ω
S
3.5
ns
F
G
L
Small-Signal Overshoot
Settling Time
V = ±15V, R = 750Ω, R = 750Ω, R = 100Ω
15
%
S
F
G
L
t
0.1%, V
= 10V, R =1k, R = 1k, R =1k
45
ns
s
OUT
F
G
L
Differential Gain, (Note 7)
Differential Phase, (Note 7)
Differential Gain, (Note 7)
Differential Phase, (Note 7)
V = ±15V, R = 750Ω, R = 750Ω, R = 1k
0.01
0.01
0.04
0.1
%
S
F
G
L
V = ±15V, R = 750Ω, R = 750Ω, R = 1k
Deg
%
S
F
G
L
V = ±15V, R = 750Ω, R = 750Ω, R = 150Ω
S
F
G
L
V = ±15V, R = 750Ω, R = 750Ω, R = 150Ω
Deg
S
F
G
L
The
range.
●
denotes specifications which apply over the operating temperature
slew rate is much higher when the input is overdriven and when the
amplifier is operated inverting, see the applications section.
Note 1: A heat sink may be required depending on the power supply
voltage and how many amplifiers are shorted.
Note 5: Rise time is measured from 10% to 90% on a ±500mV output
signal while operating on ±15V supplies with R = 1k, R = 110Ω and R =
F
G
L
100Ω. This condition is not the fastest possible, however, it does
guarantee the internal capacitances are correct and it makes automatic
testing practical.
Note 2: The power tests done on ±15V supplies are done on only one
amplifier at a time to prevent excessive junction temperatures when testing
at maximum operating temperature.
Note 6: AC parameters are 100% tested on the ceramic and plastic DIP
packaged parts (J and N suffix) and are sample tested on every lot of the
SO packaged parts (S suffix).
Note 3: The supply current of the LT1229/LT1230 has a negative
temperature coefficient. For more information see the application
information section.
Note 7: NTSC composite video with an output level of 2V .
Note 4: Slew rate is measured at ±5V on a ±10V output signal while
P
operating on ±15V supplies with R = 1k, R = 110Ω and R = 400Ω. The
F
G
L
3
LT1229/LT1230
TYPICAL PERFOR A CE CHARACTERISTICS
U W
Voltage Gain and Phase vs
Frequency, Gain = 6dB
–3dB Bandwidth vs Supply
–3dB Bandwidth vs Supply
Voltage, Gain = 2, RL = 1k
Voltage, Gain = 2, RL = 100Ω
8
7
6
0
180
160
140
180
160
140
PHASE
PEAKING ≤ 0.5dB
PEAKING ≤ 5dB
45
90
R
= 500Ω
F
GAIN
R = 500Ω
R
= 750Ω
F
F
5
4
135
180
120
100
80
60
40
20
0
120
100
80
60
40
20
0
R = 750Ω
F
3
2
1
225
R = 1k
F
PEAKING ≤ 0.5dB
PEAKING ≤ 5dB
V
= ±15V
S
L
F
0
–1
–2
R
= 2k
R
= 1k
F
R = 2k
F
F
R
= 100Ω
R = 750Ω
0
2
4
6
8
10 12 14 16 18
0.1
1
10
100
0
2
4
6
8
10 12 14 16 18
SUPPLY VOLTAGE (±V)
FREQUENCY (MHz)
SUPPLY VOLTAGE (±V)
LT1229 • TPC01
LT1229 • TPC02
LT1229 • TPC03
Voltage Gain and Phase vs
Frequency, Gain = 20dB
–3dB Bandwidth vs Supply
Voltage, Gain = 10, RL = 100Ω
–3dB Bandwidth vs Supply
Voltage, Gain = 10, RL = 1k
22
21
20
0
180
160
140
180
160
140
PHASE
PEAKING ≤ 0.5dB
PEAKING ≤ 5dB
PEAKING ≤ 0.5dB
PEAKING ≤ 5dB
45
90
GAIN
19
18
135
180
120
100
80
60
40
20
0
120
100
80
60
40
20
0
R
= 250Ω
R = 500Ω
F
F
R = 250Ω
F
17
16
15
225
R = 500Ω
F
R
= 750Ω
F
R = 750Ω
F
R = 1k
F
R = 1k
F
V
= ±15V
S
L
F
14
13
12
R
= 100Ω
R = 2k
F
R = 2k
F
R = 750Ω
0.1
1
10
100
0
2
4
6
8
10 12 14 16 18
0
2
4
6
8
10 12 14 16 18
FREQUENCY (MHz)
SUPPLY VOLTAGE (±V)
SUPPLY VOLTAGE (±V)
LT1229 • TPC04
LT1229 • TPC05
LT1229 • TPC06
Voltage Gain and Phase vs
Frequency, Gain = 40dB
–3dB Bandwidth vs Supply
Voltage, Gain = 100, RL = 100Ω
–3dB Bandwidth vs Supply
Voltage, Gain = 100, RL = 1kΩ
42
41
40
0
18
16
14
18
16
14
PHASE
45
90
R
= 500Ω
GAIN
F
39
38
135
180
12
10
8
12
10
8
R = 500Ω
F
R
= 1k
F
37
36
35
225
R = 1k
F
R
= 2k
F
6
6
R = 2k
F
4
4
V
= ±15V
34
33
32
S
L
F
R
= 100Ω
2
2
R = 750Ω
0
0
0.1
1
10
100
0
2
4
6
8
10 12 14 16 18
0
2
4
6
8
10 12 14 16 18
FREQUENCY (MHz)
SUPPLY VOLTAGE (±V)
SUPPLY VOLTAGE (±V)
LT1229 • TPC07
LT1229 • TPC08
LT1229 • TPC09
4
LT1229/LT1230
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Maximum Capacitance Load vs
Feedback Resistor
Total Harmonic Distortion vs
Frequency
2nd and 3rd Harmonic
Distortion vs Frequency
0.10
10000
1000
–20
–30
V
V
= ±15V
P-P
= 100Ω
S
O
L
V
R
R
= ±15V
= 400Ω
S
L
F
= 2V
R
V
= ±5V
= R = 750Ω
S
G
R = 750Ω
A
F
= 10dB
2ND
V
–40
–50
–60
–70
V
= ±15V
S
0.01
100
10
1
V
V
= 7V
RMS
3RD
O
O
= 1V
RMS
R
= 1k
L
PEAKING ≤ 5dB
GAIN = 2
0.001
10
100
1k
FREQUENCY (Hz)
10k
100k
0
1
2
3
1
10
FREQUENCY (MHz)
100
FEEDBACK RESISTOR (kΩ)
LT1229 • TPC11
LT1229 • TPC10
LT1229 • TPC12
Input Common-Mode Limit vs
Temperature
Output Saturation Voltage vs
Temperature
Output Short-Circuit Current vs
Junction Temperature
+
+
70
60
50
40
30
V
V
–0.5
–1.0
–1.5
–2.0
–0.5
–1.0
+
V
V
= 2V TO 18V
R
= ∞
L
±2V ≤ V ≤ ±18V
S
2.0
1.5
1.0
0.5
–
= –2V TO –18V
1.0
0.5
–
–
V
V
–50 –25
0
25 50 75 100 125 150 175
–50 –25
0
25
50
75 100 125
–50 –25
0
25
50
75 100 125
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
LT1229 • TPC15
LT1229 • TPC13
LT1229 • TPC14
Spot Noise Voltage and Current vs
Frequency
Power Supply Rejection vs
Frequency
Output Impedance vs
Frequency
100
10
1
80
60
100
10
V
= ±15V
S
V
R
R
= ±15V
S
L
F
= 100Ω
–i
n
= R = 750Ω
G
POSITIVE
1.0
R
= R = 2k
G
F
40
20
0
R
= R = 750Ω
G
F
0.1
0.01
NEGATIVE
e
n
+i
n
0.001
10k
100k
1M
10M
100M
10
100
1k
FREQUENCY (Hz)
10k
100k
10k
100k
1M
FREQUENCY (Hz)
10M
100M
FREQUENCY (Hz)
LT1229 • TPC16
LT1229 • TPC17
LT1229 • TPC18
5
LT1229/LT1230
TYPICAL PERFOR A CE CHARACTERISTICS
U W
Settling Time to 10mV vs
Output Step
Settling Time to 1mV vs
Output Step
Supply Current vs Supply Voltage
10
9
10
8
10
8
NONINVERTING
INVERTING
NONINVERTING
8
6
6
–55°C
INVERTING
7
4
4
25°C
6
2
2
V
= ±15V
G
V
= ±15V
G
S
F
S
F
5
0
0
125°C
R
= R = 1k
R = R = 1k
4
3
2
1
0
–2
–4
–2
–4
175°C
INVERTING
–6
–6
NONINVERTING
–8
–8
NONINVERTING
20
INVERTING
60 80
–10
–10
0
2
4
6
8
10 12 14 16 18
0
40
100
0
4
8
12
16
20
SUPPLY VOLTAGE (±V)
SETTLING TIME (ns)
SETTLING TIME (µs)
LT1229 • TPC21
LT1229 • TPC19
LT1229 • TPC20
W
W
SI PLIFIED SCHE ATIC
One Amplifier
+
V
+IN
–IN
V
OUT
–
V
LT1229 • TA03
6
LT1229/LT1230
O U
W
U
PPLICATI
A
S I FOR ATIO
The LT1229/LT1230 are very fast dual and quad current
feedback amplifiers. Because they are current feedback
amplifiers, theymaintaintheirwidebandwidthoverawide
range of voltage gains. These amplifiers are designed to
drive low impedance loads such as cables with excellent
linearity at high frequencies.
limited by the gain bandwidth product of about 1GHz. The
curves show that the bandwidth at a closed-loop gain of
100 is 10MHz, only one tenth what it is at a gain of two.
Capacitance on the Inverting Input
Current feedback amplifiers want resistive feedback from
the output to the inverting input for stable operation. Take
care to minimize the stray capacitance between the output
and the inverting input. Capacitance on the inverting input
to ground will cause peaking in the frequency response
(and overshoot in the transient response), but it does not
degrade the stability of the amplifier. The amount of
capacitance that is necessary to cause peaking is a func-
tion of the closed-loop gain taken. The higher the gain, the
more capacitance is required to cause peaking. We can
add capacitance from the inverting input to ground to
increase the bandwidth in high gain applications. For
example,inthisgainof100application,thebandwidthcan
be increased from 10MHz to 17MHz by adding a 2200pF
capacitor.
Feedback Resistor Selection
The small-signal bandwidth of the LT1229/LT1230 is set
bytheexternalfeedbackresistorsandtheinternaljunction
capacitors. As a result, the bandwidth is a function of the
supply voltage, the value of the feedback resistor, the
closed-loop gain and load resistor. The characteristic
curves of Bandwidth versus Supply Voltage are done with
aheavyload(100Ω)andalightload(1k)toshowtheeffect
of loading. These graphs also show the family of curves
that result from various values of the feedback resistor.
These curves use a solid line when the response has less
than 0.5dB of peaking and a dashed line when the re-
sponse has 0.5dB to 5dB of peaking. The curves stop
where the response has more than 5dB of peaking.
+
V
IN
1/2
Small-Signal Rise Time with
RF = RG = 750Ω, VS = ±15V, and RL = 100Ω
V
OUT
LT1229
–
R
F
510Ω
R
5.1Ω
G
C
G
LT1229 • TA05
Boosting Bandwidth of High Gain Amplifier with
LT1229 • TA04
Capacitance on Inverting Input
49
At a gain of two, on ±15V supplies with a 750Ω feedback
resistor, the bandwidth into a light load is over 160MHz
without peaking, but into a heavy load the bandwidth
reduces to 100MHz. The loading has so much effect
because there is a mild resonance in the output stage that
enhances the bandwidth at light loads but has its Q
reduced by the heavy load. This enhancement is only
usefulatlowgainsettings;atagainoftenitdoesnot boost
the bandwidth. At unity gain, the enhancement is so
effective the value of the feedback resistor has very little
effect. At very high closed-loop gains, the bandwidth is
46
C
= 4700pF
G
43
40
37
34
31
28
25
22
19
C
= 2200pF
G
C
= 0
G
1
10
FREQUENCY (MHz)
100
LT1229 • TA06
7
LT1229/LT1230
O U
W
U
PPLICATI
A
S I FOR ATIO
Capacitive Loads
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.
The LT1229/LT1230 can drive capacitive loads directly
when the proper value of feedback resistor is used. The
graph Maximum Capacitive Load vs Feedback Resistor
should be used to select the appropriate value. The value
shown is for 5dB peaking when driving a 1k load at a gain
of 2. This is a worst case condition; the amplifier is more
stable at higher gains and driving heavier loads. Alterna-
tively, a small resistor (10Ω to 20Ω) can be put in series
with the output to isolate the capacitive load from the
amplifier output. This has the advantage that the amplifier
bandwidth is only reduced when the capacitive load is
present, and the disadvantage that the gain is a function of
the load resistance.
For example, let’s calculate the worst case power dissipa-
tioninavideocabledriveroperatingon±12Vsuppliesthat
delivers a maximum of 2V into 150Ω.
V
O MAX
(
)
P
= 2V I
+ V – V
d MAX
S S MAX
S
O MAX
(
)
(
)
)
(
)
(
)
R
L
2V
P
= 2 × 12V × 7mA + 12V – 2V ×
(
)
d MAX
(
150Ω
= 0.168 + 0.133 = 0.301W per Amp
Power Supplies
Now if that is the dual LT1229, the total power in the
package is twice that, or 0.602W. We now must calcu-
late 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 tempera-
ture rise. For the above example, if we use the SO8
surface mount package, the thermal resistance is
150°C/W junction to ambient in still air.
The LT1229/LT1230 amplifiers will operate from single or
split supplies from ±2V (4V total) to ±15V (30V total). It is
not necessary to use equal value split supplies, however,
the offset voltage and inverting input bias current will
change. The offset voltage changes about 350µV per volt
of supply mismatch, the inverting bias current changes
about 2.5µA per volt of supply mismatch.
Temperature Rise = Pd (MAX) RθJA = 0.602W ×
150°C/W = 90.3°C
Power Dissipation
The LT1229/LT1230 amplifiers combine high speed and
large output current drive into very small packages. Be-
causetheseamplifiersworkoveraverywidesupplyrange,
itispossibletoexceedthemaximumjunctiontemperature
under certain conditions. To ensure that the LT1229 and
LT1230 remain within their absolute maximum ratings,
we must calculate the worst case power dissipation,
define the maximum ambient temperature, select the
appropriate package and then calculate the maximum
junction temperature.
The maximum junction temperature allowed in the plastic
package is 150°C. Therefore, the maximum ambient al-
lowed 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. If we must
use this package at the maximum ambient we must lower
the supply voltage or reduce the output swing.
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 LT1229/LT1230 has a strong nega-
tive temperature coefficient. The supply current of each
As a guideline to help in the selection of the LT1229/
LT1230 the following table describes the maximum sup-
ply voltage that can be used with each part in cable driving
applications.
8
LT1229/LT1230
O U
W
U
PPLICATI
A
S I FOR ATIO
Large-Signal Response, AV = 2, RF = RG = 750Ω
Assumptions:
1. The maximum ambient is 70°C for the commercial
parts (C suffix) and 125°C for the full temperature
parts (M suffix).
2. The load is a double-terminated video cable, 150Ω.
3. The maximum output voltage is 2V (peak or DC).
4. The thermal resistance of each package:
J8 is 100°C/W
N8 is 100°C/W
S8 is 150°C/W
J is 80°/W
N is 70°/W
S is 110°/W
LT1229 • TA07
Larger feedback resistors will reduce the slew rate as will
lower supply voltages, similar to the way the bandwidth is
reduced.
Maximum Supply Voltage for 75Ω Cable Driving Applications at
Maximum Ambient Temperature
PART
PACKAGE
MAX POWER AT T
MAX SUPPLY
V < ±10.1
A
Large-Signal Response, AV = 10, RF = 1k, RG = 110Ω
LT1229MJ8
LT1229CJ8
LT1229CN8
LT1229CS8
Ceramic DIP
Ceramic DIP
Plastic DIP
Plastic SO8
0.500W @ 125°C
1.050W @ 70°C
0.800W @ 70°C
0.533W @ 70°C
S
V < ±18.0
S
V < ±15.6
S
V < ±10.6
S
LT1230MJ
LT1230CJ
LT1230CN
LT1230CS
Ceramic DIP
Ceramic DIP
Plastic DIP
0.625W @ 125°C
1.313W @ 70°C
1.143W @ 70°C
0.727W @ 70°C
V < ±6.6
S
V < ±13.0
S
V < ±11.4
S
Plastic SO14
V < ±7.6
S
Slew Rate
The slew rate of a current feedback amplifier is not
independent of the amplifier gain the way it is in a tradi-
tional op amp. This is because the input stage and the
output stage both have slew rate limitations. The input
stage of the LT1229/LT1230 amplifiers slew at about
100V/µs before they become nonlinear. Faster input sig-
nals will turn on the normally reverse-biased emitters on
the input transistors and enhance the slew rate signifi-
cantly. This enhanced slew rate can be as much as
2500V/µs.
LT1229 • TA08
Settling Time
The characteristic curves show that the LT1229/LT1230
amplifiers settle to within 10mV of final value in 40ns to
55ns for any output step up to 10V. The curve of settling
to 1mV of final value shows that there is a slower thermal
contribution up to 20µs. The thermal settling component
comes from the output and the input stage. The output
contributes just under 1mV per volt of output change and
the input contributes 300µV per volt of input change.
Fortunately, the input thermal tends to cancel the output
thermal. For this reason the noninverting gain of two
configurationssettlesfasterthantheinvertinggainofone.
The output slew rate is set by the value of the feedback
resistors and the internal capacitance. At a gain of ten with
a 1k feedback resistor and ±15V supplies, the output slew
rate is typically 700V/µs and –1000V/µs. There
is no input stage enhancement because of the high gain.
9
LT1229/LT1230
O U
W
U
PPLICATI
A
S I FOR ATIO
Crosstalk and Cascaded Amplifiers
The high frequency crosstalk between amplifiers is
caused by magnetic coupling between the internal wire
bonds that connect the IC chip to the package lead frame.
The amount of crosstalk is inversely proportional to the
load resistor the amplifier is driving, with no load (just
the feedback resistor) the crosstalk improves 18dB. The
curve shows the crosstalk of the LT1229 amplifier B
output (pin 7) to the input of amplifier A. The crosstalk
from amplifier A’s output (pin 1) to amplifier B is about
10dB better. The crosstalk between all of the LT1230
amplifiers is as shown. The LT1230 amplifiers that are
separated by the supplies are a few dB better.
The amplifiers in the LT1229/LT1230 do not share any
common circuitry. The only thing the amplifiers share is
the supplies. As a result, the crosstalk between amplifiers
is very low. In a good breadboard or with a good PC board
layout the crosstalk from the output of one amplifier to the
input of another will be over 100dB down, up to 100kHz
and 65dB down at 10MHz. The following curve shows
the crosstalk from the output of one amplifier to the
input of another.
Amplifier Crosstalk vs Frequency
When cascading amplifiers the crosstalk will limit the
amount of high frequency gain that is available because
the crosstalk signal is out of phase with the input signal.
This will often show up as unusual frequency response.
For example: cascading the two amplifiers in the LT1229,
each set up with 20dB of gain and a –3dB bandwidth of
65MHz into 100Ω will result in 40dB of gain, BUT the
responsewillstarttodropatabout10MHzandthenflatten
out from 20MHz to 30MHz at about 0.5dB down. This is
due to the crosstalk back to the input of the first amplifier.
120
V
A
R
R
= ±15V
= 10
= 50Ω
= 100Ω
S
V
S
L
110
100
90
80
70
60
50
10 100
1k 10k 100k 1M 10M 100M
ForbestresultswhencascadingamplifiersusetheLT1229
and drive amplifier B and follow it with amplifier A.
FREQUENCY (Hz)
LT1229 • TA12
U
O
TYPICAL APPLICATI S
Single 5V Supply Cable Driver for Composite Video
(the sync pulses). R4, R5 and R6 set the amplifier up with
a gain of two and bias the output so the bottom of the sync
pulses are at 1.1V. The maximum input then drives the
output to 3.9V.
This circuit amplifies standard 1V peak composite video
input (1.4VP-P) by two and drives an AC coupled, doubly
terminated cable. In order for the output to swing
2.8VP-P on a single 5V supply, it must be biased accu-
rately. The average DC level of the composite input is a
function of the luminance signal. This will cause problems
if we AC couple the input signal into the amplifier because
a rapid change in luminance will drive the output into the
rails. To prevent this we must establish the DC level at the
input and operate the amplifier with DC gain.
5V
R1
3k
R4
1.5k
C3
47µF
2N3904
C2
1µF
R2
2k
C1
1µF
+
V
OUT
C4
R7
75Ω
+
1000µF
V
+
IN
1/2
LT1229
R3
150k
R6
510Ω
–
R8
10k
The transistor’s base is biased by R1 and R2 at 2V. The
emitter of the transistor clamps the noninverting input of
the amplifier to 1.4V at the most negative part of the input
R5
750Ω
LT1229 • TA11
10
LT1229/LT1230
U
O
TYPICAL APPLICATI S
Single Supply AC Coupled Amplifiers
Noninverting
Inverting
5V
4.7µF
5V
+
4.7µF
+
10kΩ
10kΩ
10k
10k
0.1µF
+
1/2
+
V
IN
V
OUT
0.1µF
LT1229
–
1/2
LT1229
V
OUT
–
4.7µF
R
51Ω
510Ω
S
4.7µF
V
51Ω
= 11
510Ω
IN
510Ω
A
=
10
V
R
+ 51Ω
A
S
V
BW = 600Hz TO 50MHz
LT1229 • TA09
LT1229 • TA10
BW = 600Hz TO 50MHz
U
PACKAGE DESCRIPTIO Dimensions in inches (millimeters) unless otherwise noted.
0.405
(10.287)
MAX
0.005
(0.127)
MIN
0.200
(5.080)
MAX
0.290 – 0.320
(7.366 – 8.128)
6
5
4
8
7
0.015 – 0.060
(0.381 – 1.524)
J8 Package
8-Lead Ceramic DIP
0.025
(0.635)
RAD TYP
0.220 – 0.310
(5.588 – 7.874)
0.008 – 0.018
(0.203 – 0.460)
0° – 15°
1
2
3
0.055
(1.397)
MAX
0.038 – 0.068
(0.965 – 1.727)
0.385 ± 0.025
(9.779 ± 0.635)
0.125
3.175
MIN
0.100 ± 0.010
0.014 – 0.026
(2.540 ± 0.254)
(0.360 – 0.660)
J8 0392
0.400
(10.160)
MAX
0.130 ± 0.005
(3.302 ± 0.127)
0.300 – 0.320
(7.620 – 8.128)
0.045 – 0.065
(1.143 – 1.651)
8
7
6
5
4
N8 Package
8-Lead Plastic DIP
0.065
(1.651)
TYP
0.250 ± 0.010
(6.350 ± 0.254)
0.009 – 0.015
(0.229 – 0.381)
0.125
(3.175)
MIN
0.020
(0.508)
MIN
+0.025
–0.015
0.045 ± 0.015
(1.143 ± 0.381)
1
2
3
0.325
+0.635
8.255
(
)
–0.381
0.100 ± 0.010
(2.540 ± 0.254)
0.018 ± 0.003
(0.457 ± 0.076)
N8 0392
0.189 – 0.197
(4.801 – 5.004)
0.010 – 0.020
(0.254 – 0.508)
7
5
8
6
× 45°
0.053 – 0.069
(1.346 – 1.752)
0.004 – 0.010
(0.101 – 0.254)
0.008 – 0.010
(0.203 – 0.254)
S8 Package
8-Lead Plastic SOIC
0.228 – 0.244
(5.791 – 6.197)
0.150 – 0.157
(3.810 – 3.988)
0.016 – 0.050
0.406 – 1.270
0.050
(1.270)
BSC
0.014 – 0.019
(0.355 – 0.483)
0°– 8° TYP
SO8 0392
1
2
3
4
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 represen-
tationthattheinterconnectionofitscircuitsasdescribedhereinwillnotinfringeonexistingpatentrights.
11
LT1229/LT1230
U
PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
J Package
14-Lead Ceramic DIP
0.785
(19.939)
MAX
0.005
(0.127)
MIN
0.200
(5.080)
MAX
0.290 – 0.320
(7.366 – 8.128)
14
13
12
11
10
9
8
0.015 – 0.060
(0.381 – 1.524)
0.220 – 0.310
0.025
(5.588 – 7.874)
(0.635)
RAD TYP
0.008 – 0.018
0° – 15°
(0.203 – 0.460)
2
3
4
5
6
1
7
0.098
(2.489)
MAX
0.385 ± 0.025
0.038 – 0.068
0.100 ± 0.010
(2.540 ± 0.254)
0.125
(3.175)
MIN
(9.779 ± 0.635)
(0.965 – 1.727)
0.014 – 0.026
(0.360 – 0.660)
J14 0392
N Package
14-Lead Plastic DIP
0.770
(19.558)
MAX
0.065
(1.651)
TYP
0.300 – 0.325
(7.620 – 8.255)
0.045 – 0.065
(1.143 – 1.651)
0.015
(0.380)
MIN
14
13
12
11
10
9
8
0.130 ± 0.005
(3.302 ± 0.127)
0.260 ± 0.010
(6.604 ± 0.254)
0.009 – 0.015
(0.229 – 0.381)
+0.025
1
2
3
5
6
7
4
0.325
–0.015
0.075 ± 0.015
(1.905 ± 0.381)
0.018 ± 0.003
(0.457 ± 0.076)
0.125
(3.175)
MIN
+0.635
8.255
(
)
–0.381
0.100 ± 0.010
(2.540 ± 0.254)
N14 0392
S Package
14-Lead Plastic SOIC
0.337 – 0.344
(8.560 – 8.738)
0.010 – 0.020
(0.254 – 0.508)
14
13
12
11
10
9
8
× 45°
0.053 – 0.069
(1.346 – 1.752)
0.008 – 0.010
(0.203 – 0.254)
0.004 – 0.010
(0.101 – 0.254)
0.228 – 0.244
0.150 – 0.157
(5.791 – 6.197)
(3.810 – 3.988)
0° – 8° TYP
0.050
(1.270)
TYP
0.016 – 0.050
0.406 – 1.270
0.014 – 0.019
(0.355 – 0.483)
SO14 0392
1
2
3
4
5
6
7
LT/GP 1092 5K REV A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7487
12
●
●
LINEAR TECHNOLOGY CORPORATION 1992
(408) 432-1900 FAX: (408) 434-0507 TELEX: 499-3977
相关型号:
SI9130DB
5- and 3.3-V Step-Down Synchronous ConvertersWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135LG-T1
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135LG-T1-E3
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135_11
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9136_11
Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130CG-T1-E3
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130LG-T1-E3
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130_11
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137DB
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137LG
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9122E
500-kHz Half-Bridge DC/DC Controller with Integrated Secondary Synchronous Rectification DriversWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
©2020 ICPDF网 联系我们和版权申明