LMH6739
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SNOSAD2G – MAY 2004 – REVISED MARCH 2013
LMH6739 Very Wideband, Low Distortion Triple Video Buffer
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FEATURES
1
•
2
•
•
•
•
•
•
•
DESCRIPTION
750 MHz −3 dB small signal bandwidth
(AV = +1)
−85 dBc 3rd harmonic distortion (20 MHz)
2.3 nV/√Hz input noise voltage
3300 V/μs slew rate
32 mA supply current (10.6 mA per op amp)
90 mA linear output current
0.02/0.01 Diff. Gain/ Diff. Phase (RL = 150Ω)
2mA shutdown current
The LMH6739 is a very wideband, DC coupled
monolithic selectable gain buffer designed specifically
for ultra high resolution video systems as well as wide
dynamic range systems requiring exceptional signal
fidelity. Benefiting from current feedback architecture,
the LMH6739 offers gains of −1, 1 and 2. At a gain of
+2 the LMH6739 supports ultra high resolution video
systems with a 400 MHz 2 VPP3 dB Bandwidth. With
12-bit distortion level through 30 MHz (RL = 100Ω),
2.3nV/√Hz input referred noise, the LMH6739 is the
ideal driver or buffer for high speed flash A/D and D/A
converters. Wide dynamic range systems such as
radar and communication receivers requiring a
wideband amplifier offering exceptional signal purity
will find the LMH6739 low input referred noise and
low harmonic distortion make it an attractive solution.
The LMH6739 is offered in a space saving SSOP
package.
APPLICATIONS
•
•
•
•
•
•
•
•
•
RGB video driver
High resolution projectors
Flash A/D driver
D/A transimpedance buffer
Wide dynamic range IF amp
Radar/communication receivers
DDS post-amps
Wideband inverting summer
Line driver
CONNECTION DIAGRAM
16-Pin SSOP
Top View
-IN A
1
+IN A
2
DIS B
3
-IN B
4
+IN B
5
DIS C
6
-IN C
7
+IN C
8
16
+
DIS A
15 +VS
14 OUT A
+
13 -VS
12 OUT B
11 +VS
+
10 OUT C
9
-VS
See Package Number DBQ0016A
1
2
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.
All 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.
Copyright © 2004–2013, Texas Instruments Incorporated
LMH6739
SNOSAD2G – MAY 2004 – REVISED MARCH 2013
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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.
Absolute Maximum Ratings
ESD Tolerance
(1)
(2)
Human Body Model
2000V
Machine Model
200V
+
–
Supply Voltage (V - V )
13.2V
(3)
IOUT
Common Mode Input Voltage
±VCC
Maximum Junction Temperature
+150°C
−65°C to +150°C
Storage Temperature Range
Soldering Information
Infrared or Convection (20 sec.)
235°C
Wave Soldering (10 sec.)
260°C
−65°C to +150°C
Storage Temperature Range
(1)
(2)
(3)
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but specific performance is not ensured. For specifications, see the Electrical
Characteristics tables.
Human Body Model, applicable std. MIL-STD-883, Method 3015.7. Machine Model, applicable std. JESD22-A115-A (ESD MM std. of
JEDEC). Field-Induced Charge-Device Model, applicable std. JESD22-C101-C (ESD FICDM std. of JEDEC).
The maximum output current (IOUT) is determined by device power dissipation limitations. See the Power Dissipation section of the
Application Information for more details.
Operating Ratings (1) (2)
Temperature Range
(3)
−40°C to +85°C
+
Supply Voltage (V - V–)
8V to 12V
Thermal Resistance
Package
16-Pin SSOP
(1)
(2)
(3)
2
(θJC)
(θJA)
36°C/W
120°C/W
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but specific performance is not ensured. For specifications, see the Electrical
Characteristics tables.
Human Body Model, applicable std. MIL-STD-883, Method 3015.7. Machine Model, applicable std. JESD22-A115-A (ESD MM std. of
JEDEC). Field-Induced Charge-Device Model, applicable std. JESD22-C101-C (ESD FICDM std. of JEDEC).
The maximum power dissipation is a function of TJ(MAX), θJA. The maximum allowable power dissipation at any ambient temperature is
PD = (TJ(MAX) – TA)/ θJA. All numbers apply for packages soldered directly onto a PC Board.
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Electrical Characteristics
(1)
TA = 25°C, AV = +2, VCC = ±5V, RL = 100Ω; unless otherwise specified.
Symbol
Parameter
Conditions
Min (2)
Typ (3)
Max (2)
Units
Frequency Domain Performance
UGBW
−3 dB Bandwidth
Unity Gain, VOUT = 200 mVPP
750
SSBW
−3 dB Bandwidth
VOUT = 200 mVPP
480
VOUT = 2 VPP
400
0.1 dB Bandwidth
VOUT = 2 VPP
150
MHz
Rolloff
at 300 MHz, VOUT = 2 VPP
1.0
dB
Rise and Fall Time
(10% to 90%)
2V Step
0.9
5V Step
1.7
SR
Slew Rate
5V Step
3300
V/µs
ts
Settling Time to 0.1%
2V Step
10
ns
te
Enable Time
From Disable = rising edge.
7.3
ns
td
Disable Time
From Disable = falling edge.
4.5
ns
2 VPP, 5 MHz
−80
2 VPP, 20 MHz
−71
2 VPP, 50 MHz
−55
2 VPP, 5 MHz
−90
2 VPP, 20 MHz
−85
2 VPP, 50 MHz
−65
LSBW
GFR2
MHz
MHz
Time Domain Response
TRS
TRL
ns
Distortion
HD2L
HD2
2nd Harmonic Distortion
HD2H
HD3L
HD3
3rd Harmonic Distortion
HD3H
dBc
dBc
Equivalent Input Noise
VN
Non-Inverting Voltage
>1 MHz
2.3
nV/√Hz
ICN
Inverting Current
>1 MHz
12
pA/√Hz
NCN
Non-Inverting Current
>1 MHz
3
pA/√Hz
Video Performance
DG
Differential Gain
4.43 MHz, RL = 150Ω
.02
%
DP
Differential Phase
4.43 MHz, RL = 150Ω
.01
degree
Static, DC Performance
(4)
VOS
Input Offset Voltage
IBN
Input Bias Current
(4)
Non-Inverting
IBI
Input Bias Current
(4)
Inverting
PSRR
Power Supply Rejection Ratio
CMRR
Common Mode Rejection Ratio
ICC
Supply Current
(4)
(4)
(4)
(2)
(3)
(4)
±2.5
±4.5
mV
−8
0
+5
µV
−2
±30
±40
μA
50
48.5
53
dB
46
44
50
dB
All three amps Enabled, No Load
32
35
40
mA
Supply Current Disabled V+
RL = ∞
1.9
2.2
mA
−
RL = ∞
1.1
1.3
mA
Supply Current Disabled V
(1)
−16
−21
0.5
Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device such that TJ = TA. Parametric performance is indicated in the electrical tables under conditions of
internal self heating where TJ> TA. See Applications Information for information on temperature de-rating of this device. Min/Max ratings
are based on product characterization and simulation. Individual parameters are tested as noted.
Limits are 100% production tested at 25°C. Limits over the operating temperature range are through correlations using the Statistical
Quality Control (SQC) method.
Typical values represent the most likely parametric norm as determined at the time of characterization. Actual typical values may vary
over time and will also depend on the application and configuration. The typical values are not tested on shipped production material.
Parameter 100% production tested at 25° C.
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Electrical Characteristics (1) (continued)
TA = 25°C, AV = +2, VCC = ±5V, RL = 100Ω; unless otherwise specified.
Symbol
Parameter
Conditions
Internal Feedback & Gain Set
Resistor Value
Min (2)
Typ (3)
Max (2)
Units
375
450
525
Ω
0.2
±1.1
%
RL = ∞
Gain Error
Miscellaneous Performance
RIN+
Non-Inverting Input Resistance
CIN+
Non-Inverting Input Capacitance
RIN−
Inverting Input Impedance
Output impedance of input buffer.
RO
Output Impedance
DC
VO
Output Voltage Range
CMIR
Linear Output Current
IO
(4)
pF
30
Ω
0.05
Ω
RL = 100Ω
±3.5
RL = ∞
±3.65
±3.5
±3.8
±1.9
±1.7
±2.0
V
90
mA
CMRR > 40 dB
(5) (4)
(6)
kΩ
.8
±3.25
±3.1
(4)
Common Mode Input Range
1000
VIN = 0V, VOUT < ±30 mV
80
60
V
ISC
Short Circuit Current
VIN = 2V Output Shorted to Ground
160
mA
IIH
Disable Pin Bias Current High
Disable Pin = V+
10
μA
IIL
Disable Pin Bias Current Low
Disable Pin = 0V
−350
VDMAX
Voltage for Disable
Disable Pin ≤ VDMAX
VDMIM
Voltage for Enable
Disable Pin ≥ VDMIN
(5)
(6)
4
μA
0.8
2.0
V
V
The maximum output current (IOUT) is determined by device power dissipation limitations. See the Power Dissipation section of the
Application Information for more details.
Short circuit current should be limited in duration to no more than 10 seconds. See the Power Dissipation section of the Application
Information for more details.
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Typical Performance Characteristics
AV = +2, VCC = ±5V, RL = 100Ω; unless otherwise specified).
Large Signal Frequency Response
Small Signal Frequency Response
4
4
VOUT = 2 VPP
AV = +1
2
AV = +1
NORMALIZED GAIN (dB)
NORMALIZED GAIN (dB)
2
0
-2
-4
AV = -1
-6
0
-2
-4
AV = -1
-6
AV = +2
-8
-8
AV = +2
-10
-10
1
10
100
Figure 1.
Figure 2.
Frequency Response
vs.
VOUT
Frequency Response vs.
Supply Voltage
1
0
-2
VOUT = 2 VPP
-5
VOUT = 1 VPP
-6
-7
-8 A = 2 V/V
V
-9
10
-1
NORMALIZED GAIN (dB)
VOUT = 4 VPP
-3
1000
VS = 7V
-2
-3
VS = 9V
-4
-5
VS = 12.5V
-6
-7
VOUT = 0.5 VPP
-8
VOUT = 2 VPP
-9
100
FREQUENCY (MHz)
1000
10
100
1000
FREQUENCY (MHz)
Figure 3.
Figure 4.
Gain Flatness
Gain Flatness, Dual Input Buffer
0.5
0.5
VOUT = 0.5 VPP
0.4
VOUT ± 250 mVPP
GAIN = +1
0.4
0.3
0.3
AV = +1
0.2
0.2
NON-INVERTING
0.1
GAIN (dB)
NORMALIZED GAIN (dB)
100
FREQUENCY (MHz)
1
-4
10
FREQUENCY (MHz)
0
-1
GAIN (dB)
1
1000
0
-0.1
0
-0.1
BOTH
AV = -1
-0.2
0.1
-0.2
-0.3
-0.3
AV = +2
-0.4
-0.4
-0.5
-0.5
1
10
100
1000
FREQUENCY (MHz)
1
10
100
1000
FREQUENCY (MHz)
Figure 5.
Figure 6.
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Typical Performance Characteristics (continued)
AV = +2, VCC = ±5V, RL = 100Ω; unless otherwise specified).
Frequency Response vs.
Capacitive Load
Pulse Response
1.5
2
1
0
0.5
-2
CL = 4.7 pF, RS = 70:
GAIN (dB)
VOUT (V)
CL = 15 pF, RS = 44:
0
CL = 47 pF, RS = 24:
-4
CL = 100 pF, RS = 17:
-0.5
-6
-1
-8
-1.5
-10
VOUT = 1 VPP, CL || 1 k:
0
4
8
12
16
20
1
10
100
1000
FREQUENCY (MHz)
TIME (ns)
Figure 7.
Figure 8.
Series Output Resistance vs.
Capacitive Load
Open Loop Gain and Phase
80
120
LOAD = 1 k: || CL
110
MAGNITUDE
60
50
40
30
20
100
90
80
0
70
-45
-90
60
PHASE
10
-135
50
0
0
20
40
60
80
100
120
40
0.01
-180
1000
100
FREQUENCY (MHz)
Figure 9.
Figure 10.
Distortion vs.
Frequency
10 MHz HD vs.
Output Level
-40
-40
VOUT = 2 VPP
-45
f = 10 MHz
-45
-50
-50
-55
-55
-60
DISTORTION (dBc)
DISTORTION (dBc)
10
1
0.1
CAPACITIVE LOAD (pF)
-60
HD2
-65
-70
-75
-80
HD3
-65
-70
HD2
-75
-80
-85
-85
HD3
-90
-90
-95
-100
-100
-95
1
10
100
FREQUENCY (MHz)
0
1
2
3
4
5
6
7
8
OUTPUT VOLTAGE (VPP)
Figure 11.
6
PHASE (°)
MAGNITUDE, |Z| (dB:)
RECOMMENDED RS (:)
70
Figure 12.
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Typical Performance Characteristics (continued)
AV = +2, VCC = ±5V, RL = 100Ω; unless otherwise specified).
Distortion vs.
Supply Voltage
CMRR vs.
Frequency
50
-65
VOUT = 2VPP
f = 10 MHz
HD2
-70
45
DISTORTION (dBc)
40
-75
CMRR (dB)
35
-80
HD3
-85
30
25
20
15
-90
10
-95
5
-100
0
6.8
7.6
8.4
9.2
0.01
10.8 11.6 12.4
10
10
1
0.1
100
1000
FREQUENCY (MHz)
TOTAL SUPPLY VOLTAGE (V)
Figure 13.
Figure 14.
PSRR vs.
Frequency
Closed Loop Output Impedance |Z|
100
60
PSRR +
AV = 2 V/V
VIN = 0V
50
10
PSRR |Z| (:)
PSRR (dB)
40
30
1
20
0.1
10
0.01
0.001 0.01
0
0.1
1
10
100
1000
0.1
1
100
10
1000
FREQUENCY (MHz)
FREQUENCY (MHz)
Figure 15.
Figure 16.
Disable Timing
DC Errors vs.
Temperature
0.6
1
6
VOUT
DISABLE (V)
OUTPUT (V)
0.2
0.0
-0.2
-0.4
-0.6
3
1
OFFSET VOLTAGE (mV)
0.4
0.8
4
0.6
2
0.4
0
VOS
0.2
-2
0
-4
-0.2
-6
-0.4
-8
IBN
DISABLE
-1
0
10
20
30
40
BIAS CURRENT (PA)
IBI
50
60
70
-0.6
-40
TIME (ns)
-10
-20
0
20
40
60
80
100
TEMPERATURE (°C)
Figure 17.
Figure 18.
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Typical Performance Characteristics (continued)
AV = +2, VCC = ±5V, RL = 100Ω; unless otherwise specified).
Crosstalk vs.
Frequency
Disabled Channel Isolation vs.
Frequency
-30
-30
CH A & C VOUT = 2 VPP
MEASURE CH B
-40
CROSSTALK (dBc)
CROSSTALK (dBc)
-40
-50
-60
-70
-80
VS = ±5V
-50
-60
-70
-80
-90
-100
-90
1
10
100
1000
0.1
1
10
100
1000
FREQUENCY (MHz)
FREQUENCY (MHz)
Figure 19.
8
VIN = 2 VPP
Figure 20.
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APPLICATION INFORMATION
+5V
+5V
6.8 µF
6.8 µF
0.01 µF
VIN
RIN
0.01 µF
VIN
CPOS
CSS
0.1 µF
+
VOUT
-
RIN
CPOS
+
CSS
0.1 µF
VOUT
-
NC
CNEG
0.01 µF
CNEG
0.01 µF
6.8 µF
6.8 µF
-5V
-5V
Figure 21. Recommended Non-Inverting Gain
Circuit, Gain = +2
Figure 22. Recommended Non-Inverting Gain
Circuit, Gain +1
+5V
6.8 µF
0.01 µF
CPOS
+
CSS
VOUT
0.1 µF
-
VIN
CNEG
RIN
0.01 µF
6.8 µF
-5V
Figure 23. Recommended Inverting Gain Circuit,
Gain = –1
GENERAL INFORMATION
The LMH6739 is a high speed current feedback selectable gain buffer (SGB), optimized for very high speed and
low distortion. With its internal feedback and gain-setting resistors the LMH6739 offers excellent AC performance
while simplifying board layout and minimizing the affects of layout related parasitic components. The LMH6739
has no internal ground reference so single or split supply configurations are both equally useful.
SETTING THE CLOSED LOOP GAIN
The LMH6739 is a current feedback amplifier with on-chip RF = RG = 450Ω. As such it can be configured with an
AV = +2, AV = +1, or an AV = −1 by connecting pins 3 and 4 as described in Table 1.
Table 1. Input Connections for all 3 Gain Possibilities
GAIN AV
INPUT CONNECTIONS
Non-Inverting
Inverting
−1 V/V
Ground
Input Signal
+1 V/V
Input Signal
NC (Open)
+2 V/V
Input Signal
Ground
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The gain of the LMH6739 is accurate to ±1% and stable over temperature. The internal gain setting resistors, RF
and RG, match very well. However, over process and temperature their absolute value will change. Using
external resistors in series with RG to change the gain will result in poor gain accuracy over temperature and
from part to part.
4
RS
100:
VIN
CP
3.3 pF
+
3
UNCOMPENSATED
2
VOUT
1
-
0
GAIN (dB)
RIN
50:
ROUT
50:
-1
CP = 1.7 pF
-2
-3
CP = 3.3 pF
-4
-5
-6
-7
-8
VOUT = 250 mVPP
10
1
100
1000
FREQUENCY (MHz)
Figure 24. Correction for Unity Gain Peaking
Figure 25. Frequency Response for Circuit in
Figure 24
UNITY GAIN COMPENSATION
With a current feedback Selectable Gain Buffer like the LMH6739, the feedback resistor is a compromise
between the value needed for stability at unity gain and the optimized value used at a gain of two. The result of
this compromise is substantial peaking at unity gain. If this peaking is undesirable a simple RC filter at the input
of the buffer will smooth the frequency response shown as Figure 24. Figure 25 shows the results of a simple
filter placed on the non-inverting input. See Figure 26 and Figure 27 for another method for reducing unity gain
peaking.
+5V
4
6.8 µF
3
PIN 4 FLOATING
2
0.01 µF
1
VIN
GAIN (dB)
RIN
0
CPOS
+
CSS
0.1 µF
VOUT
-
CNEG
-1
-2
PIN 4 SHORTED TO PIN 3
-3
-4
-5
0.01 µF
-6
VOUT = 250 mVPP
-7
-8
GAIN = +1
1
6.8 µF
10
100
1000
FREQUENCY (MHz)
-5V
Figure 26. Alternate Unity Gain Compensation
Figure 27. Frequency Response for Circuit in
Figure 26
X1
+
RIN
51:
-
+
-
ROUT
51:
CL
10 pF
RL
1 k:
Figure 28. Decoupling Capacitive Loads
10
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DRIVING CAPACITIVE LOADS
Capacitive output loading applications will benefit from the use of a series output resistor ROUT. Figure 28 shows
the use of a series output resistor, ROUT, to stabilize the amplifier output under capacitive loading. Capacitive
loads of 5 to 120 pF are the most critical, causing ringing, frequency response peaking and possible oscillation.
The charts “Suggested ROUT vs. Cap Load” give a recommended value for selecting a series output resistor for
mitigating capacitive loads. The values suggested in the charts are selected for .5 dB or less of peaking in the
frequency response. This gives a good compromise between settling time and bandwidth. For applications where
maximum frequency response is needed and some peaking is tolerable, the value of ROUT can be reduced
slightly from the recommended values.
LAYOUT CONSIDERATIONS
Whenever questions about layout arise, use the evaluation board as a guide. The LMH730275 is the evaluation
board for the LMH6739.
To reduce parasitic capacitances ground and power planes should be removed near the input and output pins.
Components in the feedback loop should be placed as close to the device as possible. For long signal paths
controlled impedance lines should be used, along with impedance matching elements at both ends.
Bypass capacitors should be placed as close to the device as possible. Bypass capacitors from each rail to
ground are applied in pairs. The larger electrolytic bypass capacitors can be located farther from the device, the
smaller ceramic capacitors should be placed as close to the device as possible. The LMH6739 has multiple
power and ground pins for enhanced supply bypassing. Every pin should ideally have a separate bypass
capacitor. Sharing bypass capacitors may slightly degrade second order harmonic performance, especially if the
supply traces are thin and /or long. In Figure 21 and Figure 22 CSS is optional, but is recommended for best
second harmonic distortion. Another option to using CSS is to use pairs of .01 μF and 0.1 μF ceramic capacitors
for each supply bypass.
VIDEO PERFORMANCE
The LMH6739 has been designed to provide excellent performance with production quality video signals in a
wide variety of formats such as HDTV and High Resolution VGA. NTSC and PAL performance is nearly flawless.
Best performance will be obtained with back terminated loads. The back termination reduces reflections from the
transmission line and effectively masks transmission line and other parasitic capacitances from the amplifier
output stage. Figure 24 shows a typical configuration for driving a 75Ω Cable. The amplifier is configured for a
gain of two to make up for the 6 dB of loss in ROUT.
MAXIMUM POWER DISSIPATION (W)
2
1.8
225 LFPM FORCED AIR
1.6
1.4
1.2
1
STILL AIR
0.8
0.6
0.4
0.2
0
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
Figure 29. Maximum Power Dissipation
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POWER DISSIPATION
The LMH6739 is optimized for maximum speed and performance in the small form factor of the standard SSOP16 package. To achieve its high level of performance, the LMH6739 consumes an appreciable amount of
quiescent current which cannot be neglected when considering the total package power dissipation limit. The
quiescent current contributes to about 40° C rise in junction temperature when no additional heat sink is used (VS
= ±5V, all 3 channels on). Therefore, it is easy to see the need for proper precautions to be taken in order to
make sure the junction temperature’s absolute maximum rating of 150°C is not violated.
To ensure maximum output drive and highest performance, thermal shutdown is not provided. Therefore, it is of
utmost importance to make sure that the TJMAX is never exceeded due to the overall power dissipation (all 3
channels).
With the LMH6739 used in a back-terminated 75Ω RGB analog video system (with 2 VPP output voltage), the
total power dissipation is around 435 mW of which 340 mW is due to the quiescent device dissipation (output
black level at 0V). With no additional heat sink used, that puts the junction temperature to about 140° C when
operated at 85°C ambient.
To reduce the junction temperature many options are available. Forced air cooling is the easiest option. An
external add-on heat-sink can be added to the SSOP-16 package, or alternatively, additional board metal
(copper) area can be utilized as heat-sink.
An effective way to reduce the junction temperature for the SSOP-16 package (and other plastic packages) is to
use the copper board area to conduct heat. With no enhancement the major heat flow path in this package is
from the die through the metal lead frame (inside the package) and onto the surrounding copper through the
interconnecting leads. Since high frequency performance requires limited metal near the device pins the best
way to use board copper to remove heat is through the bottom of the package. A gap filler with high thermal
conductivity can be used to conduct heat from the bottom of the package to copper on the circuit board. Vias to a
ground or power plane on the back side of the circuit board will provide additional heat dissipation. A combination
of front side copper and vias to the back side can be combined as well.
Follow these steps to determine the maximum power dissipation for the LMH6739:
1. Calculate the quiescent (no-load) power:
PAMP = ICC x (VS) VS = V+-V−
(1)
2. Calculate the RMS power dissipated in the output stage:
PD (rms) = rms ((VS - VOUT)*IOUT)
(2)
where VOUT and IOUT are the voltage and current across the external load and VS is the total supply current
3. Calculate the total RMS power:
PT = PAMP+PD
(3)
The maximum power that the LMH6739 package can dissipate at a given temperature can be derived with the
following equation (See Figure 29):
PMAX = (150º – TAMB)/ θJA, where TAMB = Ambient temperature (°C) and θJA = Thermal resistance, from junction
to ambient, for a given package (°C/W). For the SSOP package θJA is 120°C/W.
ESD PROTECTION
The LMH6739 is protected against electrostatic discharge (ESD) on all pins. The LMH6739 will survive 2000V
Human Body model and 200V Machine model events.
Under closed loop operation the ESD diodes have no effect on circuit performance. There are occasions,
however, when the ESD diodes will be evident. If the LMH6739 is driven by a large signal while the device is
powered down the ESD diodes will conduct.
The current that flows through the ESD diodes will either exit the chip through the supply pins or will flow through
the device, hence it is possible to power up a chip with a large signal applied to the input pins. Shorting the
power pins to each other will prevent the chip from being powered up through the input.
12
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Copyright © 2004–2013, Texas Instruments Incorporated
Product Folder Links: LMH6739
LMH6739
www.ti.com
SNOSAD2G – MAY 2004 – REVISED MARCH 2013
REVISION HISTORY
Changes from Revision F (March 2013) to Revision G
•
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 12
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Copyright © 2004–2013, Texas Instruments Incorporated
Product Folder Links: LMH6739
13
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LMH6739MQ/NOPB
ACTIVE
SSOP
DBQ
16
95
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
LH67
39MQ
LMH6739MQX/NOPB
ACTIVE
SSOP
DBQ
16
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
LH67
39MQ
(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)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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