Texas Instruments | LMH6715QML Dual Wideband Video Op Amp (Rev. B) | Datasheet | Texas Instruments LMH6715QML Dual Wideband Video Op Amp (Rev. B) Datasheet

Texas Instruments LMH6715QML Dual Wideband Video Op Amp (Rev. B) Datasheet
LMH6715QML
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LMH6715QML Dual Wideband Video Op Amp
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FEATURES
DESCRIPTION
•
The LMH6715 combines Texas Instrument's VIP10™
high speed complementary bipolar process with
Texas Instrument's current feedback topology to
produce a very high speed dual op amp. The
LMH6715 provides 400MHz small signal bandwidth at
a gain of +2V/V and 1300V/μs slew rate while
consuming only 5.8mA per amplifier from ±5V
supplies.
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•
•
•
•
•
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•
•
Available with Radiation Ensured 300 krad(Si)
TA = 25°C, RL = 100Ω, Typical Values Unless
Specified.
Very Low Diff. Gain, Phase: 0.02%, 0.02°
Wide Bandwidth: 480MHz (AV = +1V/V);
400MHz (AV = +2V/V)
0.1dB Gain Flatness to 100MHz
Low Power: 5.8mA/Channel
−70dB Channel-to-Channel Crosstalk (10MHz)
Fast Slew Rate: 1300V/μs
Unity Gain Stable
Improved Replacement for CLC412
APPLICATIONS
•
•
•
•
•
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HDTV, NTSC & PAL Video Systems
Video Switching and Distribution
IQ Amplifiers
Wideband Active Filters
Cable Drivers
DC Coupled Single-to-Differential Conversions
The LMH6715 offers exceptional video performance
with its 0.02% and 0.02° differential gain and phase
errors for NTSC and PAL video signals while driving
up to four back terminated 75Ω loads. The LMH6715
also offers a flat gain response of 0.1dB to 100MHz
and very low channel-to-channel crosstalk of −70dB
at 10MHz. Additionally, each amplifier can deliver
70mA of output current. This level of performance
makes the LMH6715 an ideal dual op amp for high
density, broadcast quality video systems.
The LMH6715's two very well matched amplifiers
support a number of applications such as differential
line drivers and receivers. In addition, the LMH6715
is well suited for Sallen Key active filters in
applications such as anti-aliasing filters for high
speed A/D converters. Its low power requirement, low
noise and distortion allow the LMH6715 to serve
portable RF applications such as IQ channels.
Connection Diagram
Top View
Figure 1. 8 Lead CDIP Package
See Package Number NAB0008A
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
1
2
3
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
VIP10 is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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Absolute Maximum Ratings (1)
Supply Voltage (VCC)
±6.75V
Common Mode Input Voltage (VCM)
V+ - V-
Differential Input Voltage
V+ - V-
Power Dissipation (PD) (2)
1.0W
Lead Temperature (Soldering, 10 seconds)
+300°C
Junction Temperature (TJ)
+175°C
-65°C ≤ TA ≤ +150 °C
Storage Temperature Range
θJA
Thermal Resistance
θJC
CDIP (Still Air)
140°C/W
CDIP (500LF/Min Air Flow)
80°C/W
CDIP
32°C/W
Package Weight (typical)
Weight CDIP
1130mg
ESD Tolerance (3)
(1)
(2)
(3)
2000V
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limit s. For ensured specifications and test conditions, see the
Electrical Characteristics. The ensured specifications apply only for the test conditions listed. Some performance characteristics may
degrade when the device is not operated under the listed test conditions.
The maximum power dissipation must be derated at elevated temperatures and is dictated by TJmax (maximum junction temperature),
θJA (package junction to ambient thermal resistance), and TA (ambient temperature). The maximum allowable power dissipation at any
temperature is PDmax = (TJmax - TA)/θJA or the number given in the Absolute Maximum Ratings, whichever is lower.
Human body model, 1.5kΩ in series with 100 pF.
Recommended Operating Ratings
Supply Voltage (VCC)
±5VDC to ±6VDC
-55°C ≤ TA ≤ +125°C
Ambient Operating Temperature Range (TA)
Quality Conformance Inspection
MIL-STD-883, Method 5005 - Group A
2
Subgroup
Description
1
Static tests at
Temp (°C)
+25
2
Static tests at
+125
3
Static tests at
-55
4
Dynamic tests at
+25
5
Dynamic tests at
+125
6
Dynamic tests at
-55
7
Functional tests at
+25
8A
Functional tests at
+125
8B
Functional tests at
-55
9
Switching tests at
+25
10
Switching tests at
+125
11
Switching tests at
-55
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LMH6715 Electrical Characteristics DC Parameter Static and DC Tests
The following conditions apply, unless otherwise specified.
RL = 100Ω, VCC = ±5VDC, AV = +2, RF = 634Ω, −55°C ≤ TA ≤ +125°C
Symbol
IBN
Parameter
Conditions
Input Bias Current, Noninverting
IBI
VIO
ICC
Supply Current
PSRR
(1)
Power Supply Rejection Ration
Subgroups
-12
12
μA
1
-12
+12
μA
2
-20
+20
μA
3
-21
+21
μA
1
-25
+25
μA
2
-35
+35
μA
3
-6
6
mV
1
-12
12
mV
2
-10
10
mV
3
14.0
mA
1
14.0
mA
2
16.0
mA
3
See (1)
See (1)
Input offset voltage
Unit
Min
See (1)
Input Bias Current, Inverting
Max
Notes
See (1)
RL =∞
+VS = +4.5V to +5.0V,
-VS = -4.5V to -5.0V
46
dB
1
44
dB
2, 3
Pre and post irradiation limits are identical to those listed under electrical characteristics. These parts may be dose rate sensitive in a
space environment and demonstrate enhanced low dose rate effect. Radiation end point limits for the noted parameters are ensured
only for the conditions as specified in MIL-STD-883, Method 1019.
LMH6715 Electrical Characteristics AC Parameter Frequeuncy Domain Response
The following conditions apply, unless otherwise specified.
RL = 100Ω, VCC = ±5VDC, AV = +2, RF = 634Ω, −55°C ≤ TA ≤ +125°C
Symbol
Parameter
Conditions
Notes
Min
175
Max
Unit
Subgroups
SSBW
Small signal bandwith
−3dB BW, VOUT < 0.5 VPP
See (1)
MHz
4
GFP
Gain flatness peaking high
0.1MHz to 30 MHz,
VOUT ≤ 0.5VPP
See (1)
0.1
dB
4
GFR
Gain flatness rolloff
0.1MHz to 30 MHz,
VOUT ≤ 0.5VPP
See (1)
0.3
dB
4
(1)
Group A testing only.
LMH6715 Electrical Characteristics AC Parameter Distortion and Noise Response
The following conditions apply, unless otherwise specified.
RL = 100Ω, VCC = ±5VDC, AV = +2, RF = 634Ω, −55°C ≤ TA ≤ +125°C
Symbol
HD2
HD3
(1)
Parameter
Second harmonic distortion
Third harmonic distortion
Conditions
Notes
Min
Max
Unit
Subgroups
2VPP at 20 MHz
See (1)
-42
dBc
4
2VPP at 20 MHz
(1)
-46
dBc
4
See
Group A testing only.
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LMH6715 Electrical Characteristics DC Parameter Drift Values
The following conditions apply, unless otherwise specified.
Deltas not required on B Level product. Deltas required for S Level product at Group B5 only, or as specified on the Internal
Processing Instructions (IPI).
Symbol
IBN
Parameter
Conditions
Input Bias Current, Noninverting
Notes
Min
Max
Unit
Subgroups
See (1)
-1.2
+1.2
μA
1
(1)
IBI
Input Bias Current, Inverting
See
-2.0
+2.0
μA
1
VIO
Input Offset Voltage
See (1)
-1.0
+1.0
mV
1
ICC
Supply Current
See (1)
-1.0
+1.0
mA
1
(1)
RL = ∞
If not tested, shall be specified to the limits specified.
0.025
0.025
0.02
0.015
0.015
PHASE
0.01
0.01
0.005
0.005
DIFFERENTIAL PHASE (°)
DIFFERENTIAL GAIN (%)
GAIN
0.02
f = 3.58MHZ
0
0
1
3
2
4
NUMBER OF 150: VIDEO LOADS
Figure 2. Differential Gain and Phase with Multiple Video Loads
2
VO = .5VPP
1
GAIN
0
VO = 1VPP
-2
PHASE
-3
0
-45
-4
VO = 2VPP
-5
-6
-90
-135
RF = 300:
-7
PHASE (°)
GAIN (dB)
-1
VO = 4VPP
-180
AV = 2V/V
-8
-225
1
10
100
1k
FREQUENCY (MHz)
Figure 3. Frequency Response vs. VOUT
4
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Typical Performance Characteristics
(TA = 25°C, VCC = ±5V, AV = ±2V/V, RF = 500Ω, RL = 100Ω, unless otherwise specified).
Non-Inverting Frequency Response
Inverting Frequency Response
2
2
AV = 1
1
1
RF = 1k:
GAIN
-3
0
PHASE
-4
RF = 150:
-6
AV = 8
-7
VO = .5VPP
RF = 350:
-8
100
10
FREQUENCY (MHz)
1
PHASE
-3
0
-4
-45
-90
-5
-90
-135
-6
-180
-7
-225
-8
-45
AV = 4
-5
AV = -2
-2
AV = -5
-135
VO = .5VPP
-180
RF = 250:
-225
1
1k
100
10
1k
FREQUENCY (MHz)
Figure 4.
Figure 5.
Non-Inverting Frequency Response
vs.
VOUT
Small Signal Channel Matching
2
2
VO = .5VPP
1
1
GAIN
GAIN
0
-1
-1
PHASE
-3
0
-4
-45
VO = 2VPP
-5
-90
CHANNEL A
CHANNEL B
-2
PHASE
-3
0
-4
-45
PHASE A
-5
PHASE (°)
VO = 1VPP
-2
MAGNITUDE (dB)
0
PHASE (°)
GAIN (dB)
PHASE (°)
RF = 500:
GAIN (dB)
-1
AV = 2
-2
PHASE (°)
-1
GAIN (dB)
AV = -1
GAIN
0
0
-90
PHASE B
RF = 300:
-7
VO = 4VPP
AV = 2V/V
-8
1
100
10
-135
-6
-180
-7
-225
-8
-135
VO = .5VPP
RF = 500:
1k
100
10
FREQUENCY (MHz)
1
FREQUENCY (MHz)
-225
1k
Figure 6.
Figure 7.
Frequency Response
vs.
Load Resistance
Non-Inverting Frequency Response
vs.
RF
2
1
GAIN
GAIN
RL = 525:
-4
-45
-90
RL = 50:
-6 RF = 500:
AV = 2
-7
100
1
10
FREQUENCY (MHz)
-135
-180
1k
GAIN (dB)
0
PHASE (°)
PHASE
-5 V = .5V
O
PP
RF = 500:
-1
RL = 100:
-3
RF = 200:
0
-1
-2
RF = 300:
1
0
GAIN (dB)
-180
-2
PHASE
-3
0
-4
-45
-5
-90
-6
-135
RF = 700:
VO = .5VPP
-7
PHASE (°)
-6
-180
AV = 2
-8
-225
1
10
100
1k
FREQUENCY (MHz)
Figure 8.
Figure 9.
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Typical Performance Characteristics (continued)
(TA = 25°C, VCC = ±5V, AV = ±2V/V, RF = 500Ω, RL = 100Ω, unless otherwise specified).
Small Signal Pulse Response
Large Signal Pulse Response
0.5
3
RF = 300:
VO = .5VPP
2
0.25
VOUT (V)
VOUT (V)
1
0
0
-1
-0.25
RF = 300:
-2
VO = 4VPP
-0.5
-3
0
5
10 15 20 25 30 35 40 45 50
0
5
TIME (ns)
10 15 20 25 30 35 40 45 50
TIME (ns)
Figure 10.
Figure 11.
Input-Referred Crosstalk
Settling Time
vs.
Accuracy
-20
1
RF = 300:
VO = .5VPP
SETTLING ACCURACY (%)
CROSSTALK (dBc)
-30
-40
-50
-60
-70
0.1
-80
-90
0.01
10
100
FREQUENCY (MHz)
1
1k
0
5
10 15 20 25 30 35 40 45 50
TIME (ns)
Figure 12.
Figure 13.
−3dB Bandwidth
vs.
VOUT
DC Errors
vs.
Temperature
500
-1
1.2
RF = 300:
0.8
-3
350
0.6
-4
300
250
VOS
-5
0.4
0.2
-6
IBI
200
0
-7
150
-0.2
-8
100
-0.4
-40
0.5
1
1.5
2
2.5
3
3.5
4
VOUT (VPP)
0
40
80
120
IBI and IBN (PA)
IBN
0
-9
160
TEMPERATURE (°)
Figure 14.
6
-2
1
400
VOS (mV)
-3dB BANDWIDTH (MHz)
450
Figure 15.
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Typical Performance Characteristics (continued)
(TA = 25°C, VCC = ±5V, AV = ±2V/V, RF = 500Ω, RL = 100Ω, unless otherwise specified).
Equivalent Input Noise
vs.
Frequency
Open Loop Transimpedance, Z(s)
120
110
120
PHASE
80
100
70
80
60
60
50
PHASE (°)
140
90
100
100
INVERTING CURRENT
NOISE
10
10
VOLTAGE NOISE
40
40
0.001 0.01
0.1
1
100
10
NON-INVERTING
CURRENT NOISE
1
20
1000
1
10
100
1k
10k
100k
1M
FREQUENCY (MHz)
FREQUENCY (Hz)
Figure 16.
Figure 17.
Differential Gain & Phase
vs.
Load
Differential Gain
vs.
Frequency
0.025
0.025
CURRENT NOISE (pA/ Hz)
100
VOLTAGE NOISE (nV/ Hz)
160
MAGNITUDE
MAGNITUDE (dB)
1000
1000
180
1
10M
0.025
RL = 37.5:
0.015
0.015
PHASE
0.01
0.01
0.005
0.005
0.02
DIFFERENTIAL GAIN (%)
0.02
0.02
DIFFERENTIAL PHASE (°)
DIFFERENTIAL GAIN (%)
GAIN
0.015
RL = 50:
RL = 150:
RL = 75:
0.01
0.005
f = 3.58MHZ
0
0
1
3
2
0
4
2
4
NUMBER OF 150: VIDEO LOADS
10
6
8
FREQUENCY (MHz)
Figure 18.
Figure 19.
Differential Phase
vs.
Frequency
Gain Flatness & Linear Phase Deviation
0.06
0.1
0.25
RL = 37.5:
PHASE
0.125
0.05
RL = 75:
0.03
RL = 150:
0
0
0.02
GAIN
LINEAR PHASE(°)
RL = 50:
0.04
GAIN (dB)
DIFFERENTIAL PHASE (°)
0.05
-0.125
-0.05
0.01
RF = 300:
VO = .5VPP
0
-0.1
2
4
6
8
10
0
FREQUENCY (MHz)
30
60
90
120
-0.25
150
FREQUENCY (MHz)
Figure 20.
Figure 21.
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Typical Performance Characteristics (continued)
(TA = 25°C, VCC = ±5V, AV = ±2V/V, RF = 500Ω, RL = 100Ω, unless otherwise specified).
2nd Harmonic Distortion
vs.
Output Voltage
3rd Harmonic Distortion
vs.
Output Voltage
-40
-30
50MHz
-60
20MHz
-40
-50
3rd HARMONIC (dBc)
2nd HARMONIC (dBc)
RF = 500:
-50
10MHz
-70
-80
5MHz
-90
50MHz
-60
20MHz
-70
-80
10MHz
-90
RF = 500:
5MHz
-100
-100
2
1
0
4
3
VOUT (VPP)
6
5
0
7
1
2
3
4
5
6
7
VOUT (VPP)
Figure 22.
Figure 23.
Closed Loop Output Resistance
PSRR & CMRR
70
100
RF = 500:
PSRR
10
CMRR and PSRR (dB)
OUTPUT RESISTANCE (:)
60
1
0.1
50
40
CMRR
30
20
10
RL = 500:
0.01
0.01
0.1
1
10
100
0
0.01
1k
FREQUENCY (MHz)
Figure 24.
0.1
10
1
100
FREQUENCY (MHz)
1k
Figure 25.
Suggested RS
vs.
CL
100
90
SUGGESTED RS (:)
80
70
60
50
40
30
20
10
0
10
100
1000
CAPACITIVE LOAD (pF)
Figure 26.
8
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APPLICATION SECTION
Figure 27. Non-Inverting Configuration with Power Supply Bypassing
Figure 28. Inverting Configuration with Power Supply Bypassing
Application Introduction
Offered in an 8-pin package for reduced space and cost, the wideband LMH6715 dual current-feedback op amp
provides closely matched DC and AC electrical performance characteristics making the part an ideal choice for
wideband signal processing. Applications such as broadcast quality video systems, IQ amplifiers, filter blocks,
high speed peak detectors, integrators and transimpedance amplifiers will all find superior performance in the
LMH6715 dual op amp.
FEEDBACK RESISTOR SELECTION
One of the key benefits of a current feedback operational amplifier is the ability to maintain optimum frequency
response independent of gain by using appropriate values for the feedback resistor (RF). The Electrical
Characteristics and Typical Performance plots specify an RF of 500Ω, a gain of +2V/V and ±5V power supplies
(unless otherwise specified). Generally, lowering RF from it's recommended value will peak the frequency
response and extend the bandwidth while increasing the value of RF will cause the frequency response to roll off
faster. Reducing the value of RF too far below it's recommended value will cause overshoot, ringing and,
eventually, oscillation.
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2
RF = 300:
1
GAIN
RF = 200:
0
GAIN (dB)
-2
PHASE
-3
0
-4
-45
-5
-90
-6
-135
RF = 700:
VO = .5VPP
-7
PHASE (°)
RF = 500:
-1
-180
AV = 2
-8
-225
1
10
100
1k
FREQUENCY (MHz)
Figure 29. Frequency Response vs. RF
The plot labeled “Frequency Response vs. RF” shows the LMH6715's frequency response as RF is varied (RL =
100Ω, AV = +2). This plot shows that an RF of 200Ω results in peaking and marginal stability. An RF of 300Ω
gives near maximal bandwidth and gain flatness with good stability, but with very light loads (RL > 300Ω) the
device may show some peaking. An RF of 500Ω gives excellent stability with good bandwidth and is the
recommended value for most applications. Since all applications are slightly different it is worth some
experimentation to find the optimal RF for a given circuit. For more information see Application Note OA-13 which
describes the relationship between RF and closed-loop frequency response for current feedback operational
amplifiers.
When configuring the LMH6715 for gains other than +2V/V, it is usually necessary to adjust the value of the
feedback resistor. The two plots labeled “RF vs. Non-inverting Gain” and “RF vs. Inverting Gain” provide
recommended feedback resistor values for a number of gain selections.
FEEDBACK RESISTOR RF (:)
1000
900
800
700
600
500
400
300
200
100
1
2
3
4
5
6
GAIN (V/V)
7
8
9
10
Figure 30. RF vs. Non-Inverting Gain
Both plots show the value of RF approaching a minimum value (dashed line) at high gains. Reducing the
feedback resistor below this value will result in instability and possibly oscillation. The recommended value of RF
is depicted by the solid line, which begins to increase at higher gains. The reason that a higher RF is required at
higher gains is the need to keep RG from decreasing too far below the output impedance of the input buffer. For
the LMH6715 the output resistance of the input buffer is approximately 160Ω and 50Ω is a practical lower limit for
RG. Due to the limitations on RG the LMH6715 begins to operate in a gain bandwidth limited fashion for gains of
±5V/V or greater.
10
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500
FEEDBACK RESISTOR RF (:)
450
400
350
300
250
200
150
100
1
2
3
4
5
6
7
8
9
10
GAIN (V/V)
Figure 31. RF vs. Inverting Gain
When using the LMH6715 as a replacement for the CLC412, identical bandwidth can be obtained by using an
appropriate value of RF . The chart “Frequency Response vs. RF” shows that an RF of approximately 700Ω will
provide bandwidth very close to that of the CLC412. At other gains a similar increase in RF can be used to match
the new and old parts.
CIRCUIT LAYOUT
With all high frequency devices, board layouts with stray capacitances have a strong influence over AC
performance. The LMH6715 is no exception and its input and output pins are particularly sensitive to the coupling
of parasitic capacitances (to AC ground) arising from traces or pads placed too closely (<0.1”) to power or
ground planes. In some cases, due to the frequency response peaking caused by these parasitics, a small
adjustment of the feedback resistor value will serve to compensate the frequency response. Also, it is very
important to keep the parasitic capacitance across the feedback resistor to an absolute minimum.
The performance plots in the data sheet can be reproduced using the evaluation boards available from Texas
Instruments. The LMH730036 board uses all SMT parts for the evaluation of the LMH6715. The board can serve
as an example layout for the final production printed circuit board.
Care must also be taken with the LMH6715's layout in order to achieve the best circuit performance, particularly
channel-to-channel isolation. The decoupling capacitors (both tantalum and ceramic) must be chosen with good
high frequency characteristics to decouple the power supplies and the physical placement of the LMH6715's
external components is critical. Grouping each amplifier's external components with their own ground connection
and separating them from the external components of the opposing channel with the maximum possible distance
is recommended. The input (RIN) and gain setting resistors (RF) are the most critical. It is also recommended that
the ceramic decoupling capacitor (0.1μF chip or radial-leaded with low ESR) should be placed as closely to the
power pins as possible.
POWER DISSIPATION
Follow these steps to determine the Maximum power dissipation for the LMH6715:
1. Calculate the quiescent (no-load) power: PAMP = ICC (VCC - VEE)
2. Calculate the RMS power at the output stage: PO = (VCC -VLOAD)(ILOAD), where VLOAD and ILOAD are the voltage
and current across the external load.
3. Calculate the total RMS power: Pt = PAMP + PO
The maximum power that the LMH6715, package can dissipate at a given temperature can be derived with the
following equation:
Pmax = (150º - Tamb)/ θJA
where
•
•
Tamb = Ambient temperature (°C)
θJA = Thermal resistance, from junction to ambient, for a given package (°C/W)
(1)
For the CDIP package θJA is 140°C/W.
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11
LMH6715QML
SNOSAQ3B – NOVEMBER 2010 – REVISED MAY 2013
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MATCHING PERFORMANCE
With proper board layout, the AC performance match between the two LMH6715's amplifiers can be tightly
controlled as shown in Typical Performance plot labeled “Small-Signal Channel Matching”.
The measurements were performed with SMT components using a feedback resistor of 300Ω at a gain of +2V/V.
The LMH6715's amplifiers, built on the same die, provide the advantage of having tightly matched DC
characteristics.
SLEW RATE AND SETTLING TIME
One of the advantages of current-feedback topology is an inherently high slew rate which produces a wider full
power bandwidth. The LMH6715 has a typical slew rate of 1300V/µs. The required slew rate for a design can be
calculated by the following equation:
SR = 2πfVpk
(2)
Careful attention to parasitic capacitances is critical to achieving the best settling time performance. The
LMH6715 has a typical short term settling time to 0.05% of 12ns for a 2V step. Also, the amplifier is virtually free
of any long term thermal tail effects at low gains.
When measuring settling time, a solid ground plane should be used in order to reduce ground inductance which
can cause common-ground-impedance coupling. Power supply and ground trace parasitic capacitances and the
load capacitance will also affect settling time.
Placing a series resistor (Rs) at the output pin is recommended for optimal settling time performance when
driving a capacitive load. The Typical Performance plot labeled “RS and Settling Time vs. Capacitive Load”
provides a means for selecting a value of Rs for a given capacitive load.
DC AND NOISE PERFORMANCE
A current-feedback amplifier's input stage does not have equal nor correlated bias currents, therefore they
cannot be canceled and each contributes to the total DC offset voltage at the output by the following equation:
(3)
The input resistance is the resistance looking from the non-inverting input back toward the source. For inverting
DC-offset calculations, the source resistance seen by the input resistor Rg must be included in the output offset
calculation as a part of the non-inverting gain equation. Application Note OA-7 gives several circuits for DC offset
correction. The noise currents for the inverting and non-inverting inputs are graphed in the Typical Performance
plot labeled “Equivalent Input Noise”. A more complete discussion of amplifier input-referred noise and external
resistor noise contribution can be found in Application Note OA-12.
DIFFERENTIAL GAIN & PHASE
The LMH6715 can drive multiple video loads with very low differential gain and phase errors. The Typical
Performance plots labeled “Differential Gain vs. Frequency” and “Differential Phase vs. Frequency” show
performance for loads from 1 to 4. The Electrical Characteristics table also specifies performance for one 150Ω
load at 4.43MHz. For NTSC video, the performance specifications also apply. Application Note OA-24
“Measuring and Improving Differential Gain & Differential Phase for Video”, describes in detail the techniques
used to measure differential gain and phase.
I/O VOLTAGE & OUTPUT CURRENT
The usable common-mode input voltage range (CMIR) of the LMH6715 specified in the Electrical Characteristics
table of the data sheet shows a range of ±2.2 volts. Exceeding this range will cause the input stage to saturate
and clip the output signal.
The output voltage range is determined by the load resistor and the choice of power supplies. With ±5 volts the
class A/B output driver will typically drive ±3.9V into a load resistance of 100Ω. Increasing the supply voltages
will change the common-mode input and output voltage swings while at the same time increase the internal
junction temperature.
12
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LMH6715QML
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SNOSAQ3B – NOVEMBER 2010 – REVISED MAY 2013
Applications Circuits
SINGLE-TO-DIFFERENTIAL LINE DRIVER
The LMH6715's well matched AC channel-response allows a single-ended input to be transformed to highly
matched push-pull driver. From a 1V single-ended input the circuit of Figure 32 produces 1V differential signal
between the two outputs. For larger signals the input voltage divider (R1 = 2R2) is necessary to limit the input
voltage on channel 2.
Figure 32. Single-to-Differential Line Driver
DIFFERENTIAL LINE RECEIVER
Figure 33 and Figure 34 show two different implementations of an instrumentation amplifier which convert
differential signals to single-ended. Figure 34 allows CMRR adjustment through R2.
Figure 33. Differential Line Receiver
Figure 34. Differential Line Receiver with CMRR Adjustment
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SNOSAQ3B – NOVEMBER 2010 – REVISED MAY 2013
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NON-INVERTING CURRENT-FEEDBACK INTEGRATOR
The circuit of Figure 35 achieves its high speed integration by placing one of the LMH6715's amplifiers in the
feedback loop of the second amplifier configured as shown.
Figure 35. Current Feedback Integrator
LOW NOISE WIDE-BANDWIDTH TRANSIMPEDANCE AMPLIFIER
Figure 36 implements a low noise transimpedance amplifier using both channels of the LMH6715. This circuit
takes advantage of the lower input bias current noise of the non-inverting input and achieves negative feedback
through the second LMH6715 channel. The output voltage is set by the value of RF while frequency
compensation is achieved through the adjustment of RT.
Figure 36. Low-Noise, Wide Bandwidth, Transimpedance Amp.
Revision History
Date Released
Section
Changes
11/30/2010
A
New Corporate Format Release
1 MDS data sheets converted into a Corp. data sheet
format. Following MDS data sheet will be Archived
MNLMH6715-X-RH, Rev. 0A0
07/12/2011
B
Connection Diagrams
Replaced 8 Lead CDIP (NAB0008A) diagram
depicting single Op Amp with diagram depicting dual
Op Amp.
14
Revision
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PACKAGE OPTION ADDENDUM
www.ti.com
25-Oct-2016
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
5962-0254701QPA
ACTIVE
CDIP
NAB
8
40
TBD
Call TI
Call TI
-55 to 125
LMH6715J-QML
5962-02547
01QPA Q ACO
01QPA Q >T
5962F0254701VPA
ACTIVE
CDIP
NAB
8
40
TBD
Call TI
Call TI
-55 to 125
LMH6715JFQV
5962F02547
01VPA Q ACO
01VPA Q >T
LMH6715J-QML
ACTIVE
CDIP
NAB
8
40
TBD
Call TI
Call TI
-55 to 125
LMH6715J-QML
5962-02547
01QPA Q ACO
01QPA Q >T
LMH6715JFQMLV
ACTIVE
CDIP
NAB
8
40
TBD
Call TI
Call TI
-55 to 125
LMH6715JFQV
5962F02547
01VPA Q ACO
01VPA Q >T
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
25-Oct-2016
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
OTHER QUALIFIED VERSIONS OF LMH6715QML, LMH6715QML-SP :
• Military: LMH6715QML
• Space: LMH6715QML-SP
NOTE: Qualified Version Definitions:
• Military - QML certified for Military and Defense Applications
• Space - Radiation tolerant, ceramic packaging and qualified for use in Space-based application
Addendum-Page 2
MECHANICAL DATA
NAB0008A
J08A (Rev M)
www.ti.com
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