LMH6704
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SNOSAD0C – FEBRUARY 2005 – REVISED MARCH 2013
LMH6704 650 MHz Selectable Gain Buffer with Disable
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FEATURES
1
•
23
•
•
•
•
•
Wideband operation
– AV = +1, VO = 0.5 VPP 650 MHz
– AV = +2, VO = 0.5 VPP 450 MHz
– AV = +2, VO = 2 VPP 400 MHz
High output current ±90 mA
Very low distortion
– 2nd/3rd harmonics (10 MHz, RL = 100Ω):
−62/−78dBc
– Differential gain/Differential phase:
0.02%/0.02°
Low noise 2.3nV/√Hz
High slew rate 3000 V/μs
Supply current 11.5 mA
APPLICATIONS
•
•
•
•
•
•
HDTV, NTSC and PAL video systems
Video switching and distribution
ADC driver
DAC buffer
RGB driver
High speed multiplexer
DESCRIPTION
The LMH™6704 is a very wideband, DC coupled
selectable gain buffer designed specifically for wide
dynamic range systems requiring exceptional signal
fidelity. The LMH6704 includes on chip feedback and
gain set resistors, simplifying PCB layout while
providing user selectable gains of +1, +2 and −1 V/V.
The LMH6704 provides a disable pin, which places
the amplifier in a high output impedance, low power
mode. The Disable pin may be allowed to float high.
With a 650 MHz Small Signal Bandwidth (AV = +1),
full power gain flatness to 200 MHz, and excellent
Differential Gain and Phase, the LMH6704 is
optimized for video applications. High resolution video
systems will benefit from the LMH6704 ability to drive
multiple video loads at low levels of differential gain
or differential phase distortion.
The LMH6704 is constructed with proprietary high
speed complementary bipolar process using proven
current feedback circuit architectures. It is available in
8 Pin SOIC and 6 Pin SOT-23 packages.
CONNECTION DIAGRAM
6 Pin SOT-23
Top View
8 Pin SOIC
Top View
1
465:
1
N/C
-IN
+IN
2 465:
3
6
VS
OUT
8
-
7
+
6
+
VS
465:
-
2
5
VS
OUT
+
-
4
5
4
-IN
+IN
N/C
See Package Number D0008A
DIS
-
3
VS
+
DIS
465:
See Package Number DBV0006A
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.
LMH 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.
Copyright © 2005–2013, Texas Instruments Incorporated
LMH6704
SNOSAD0C – FEBRUARY 2005 – 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
(2)
(1)
Human Body Model
2000V
Machine Model
200V
Supply Voltage
13.5V
(3)
IOUT
VS−
Common-Mode Input Voltage
Maximum Junction Temperature
150°C
−65°C to 150°C
Storage Temperature Range
Soldering Information
(1)
(2)
(3)
to VS+
Infrared or Convection (20 sec.)
235°C
Wave Soldering (10 sec.)
260°C
Lead Temp. (soldering 10 sec.)
300°C
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.
Operating Ratings (1)
Nominal Supply Voltage
Temperature Range
±4V to ±6V
(2)
−40°C to 85°C
Thermal Resistance
(1)
(2)
2
Package
(θJC)
(θJA)
8-Pin SOIC
75°C/W
160°C/W
6-Pin SOT23
120°C/W
187°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.
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, VS = ±5V, RL = 100Ω; unless specified.
Symbol
Parameter
Conditions
Min
(2)
Typ
(2)
Max
(2)
Units
Dynamic Performance
SSBW
SSBW
-3 dB Bandwidth
LSBW
VOUT = 0.5 VPP, AV = +1
650
VOUT = 0.5 VPP
450
VOUT = 2 VPP
400
GF0.1dB
0.1 dB Gain Bandwidth
VOUT = 2 VPP
SR
Slew Rate
VOUT = 4 VPP, 40% to 60%
TRS/TRL
Rise and Fall Time
(10% to 90%)
ts
Settling Time to 0.1%
MHz
200
MHz
3000
V/µs
2V Step
0.9
ns
2V Step
10
ns
VOUT = 2.0 VPP, f = 10 MHz
−62
VOUT = 2.0 VPP, f = 40 MHz
−52
VOUT = 2.0 VPP, f = 10 MHz
−78
VOUT = 2.0 VPP, f = 40 MHz
−65
(3)
Distortion and Noise Response
HD2L
2nd Harmonic Distortion
HD2H
HD3L
3rd Harmonic Distortion
HD3H
IMD
Two-Tone Intermodulation
dBc
−65
f = 10 MHz, POUT = 10 dBm/tone
f = 100 kHz
dBc
AV = +2
10.5
AV = +1
9.3
AV = −1
10.5
dBc
VN
Output Noise Voltage
nV/√Hz
INN
Non-Inverting Input Noise Current
DG
Differential Gain
RL = 150Ω, f = 4.43 MHz
.02
%
DP
Differential Phase
RL = 150Ω, f = 4.43 MHz
0.02
deg
3
pA/√Hz
Static, DC Performance
AV
1.98
1.96
Gain
−1
−2
Gain Error
VIO
Input Offset Voltage
DVIO
Input Offset Voltage Average Drift
2
Input Bias Current
IBI
Input Bias Current
Inverting
CMIR
Common Mode Input Range
VIO ≤ 15 mV
PSRR
Power Supply Rejection Ratio
DC
Output Voltage Swing
IO
Linear Output Current
(4)
(2)
(3)
(4)
V/V
+1
+2
%
±7
±8.3
mV
−5
μV/°C
5
±15
±18
μA
±22
±31
±1.9
±2
V
48
47
52
dB
RL = ∞
±3.3
±3.18
±3.5
RL = 100Ω
±3.2
±3.12
±3.5
VOUT ≤ 80 mV
Supply Current (Enabled)
DIS = 2V, RL = ∞
Supply Current (Disabled)
DIS = 0.8V, RL = ∞
IS
(1)
2.02
2.04
35
Non-Inverting
IBN
VO
2.00
±55
V
±90
mA
11.5
12.5
13.7
0.25
0.9
0.925
mA
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. Min/Max ratings are based on production testing unless otherwise specified.
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.
Slew Rate is the average of the rising and falling edges.
Negative current implies current flowing out of the device.
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Electrical Characteristics (1) (continued)
TA = +25°C , AV = +2, VS = ±5V, RL = 100Ω; unless specified.
Symbol
Parameter
RF & RG
Internal RF and RG
ROUT
Closed Loop Output Resistance
RIN+
CIN+
Conditions
Min
(2)
375
Typ
(2)
465
Max
(2)
563
Units
Ω
0.05
Ω
Input Resistance
1
MΩ
Input Capacitance
1
pF
DC
Enable/Disable Performance (Disabled Low)
TON
Enable Time
10
ns
TOFF
Disable Time
10
ns
50
mVPP
Output Glitch
VIH
Enable Voltage
DIS ≥ VIH
VIL
Disable Voltage
DIS ≤ VIL
IIH
Disable Input Bias Current, High
DIS = V+,
(4)
DIS = 0V
(4)
IIL
IOZ
4
Disable Input Bias Current, Low
Disabled Output Leakage Current
2.0
V
0.8
AV = +1, VOUT = ±1.8V
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0
−1
±50
µA
−100
−350
µA
0.2
±25
±50
µA
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Typical Performance Characteristics
(TA = 25°C, VS = ±5V, RL = 100Ω, AV = +2, VOUT = 0.5 VPP; Unless Specified).
Small Signal Frequency Response
vs.
Gain
Frequency Response
vs.
VOUT
4
7
AV = +1
2
6
5
AV = -1
1
4
0
GAIN (dB)
NORMALIZED GAIN (dB)
3
-1
AV = +2
-2
2
0
-4
-1
-5
-2
1
10
100
VOUT = 2 VPP
1
-3
-6
VOUT = 4 VPP
3
VOUT = 0.5 VPP
-3
0.1
1000
1
Figure 1.
Figure 2.
6.5
6
6.4
5
6.3
GAIN (dB)
2
RL = 100:
1
0
6.1
6
5.9
5.8
RL = 1k:
-1
VOUT = 2 VPP
6.2
RL = 50:
3
1000
Large Signal Gain Flatness
7
4
GAIN (dB)
100
FREQUENCY (MHz)
Small Signal Frequency Response
vs.
RLOAD
5.7
-2
5.6
-3
0.1
1
10
100
5.5
0.1
1000
1
10
100
1000
FREQUENCY (MHz)
FREQUENCY (MHz)
Figure 3.
Figure 4.
Small Signal Frequency Response
vs.
Capacitive Load
Series Output Isolation Resistance
vs.
Capacitive Load
70
8
CL = 4.7 pF, RISO = 56:
7
60
RECOMMENDED RISO (:)
6
5
GAIN (dB)
10
FREQUENCY (MHz)
CL = 15 pF, RISO = 39:
4
3
CL = 47 pF, RISO = 22:
2
1
CL = 100 pF, RISO = 15:
0
50
40
30
20
10
-1
0
-2
1
10
100
1000
0
20
40
60
80
FREQUENCY (MHz)
CAPACITIVE LOAD (pF)
Figure 5.
Figure 6.
100
120
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Typical Performance Characteristics (continued)
(TA = 25°C, VS = ±5V, RL = 100Ω, AV = +2, VOUT = 0.5 VPP; Unless Specified).
Small Signal Pulse Response
0.5
2
0.4
1.5
0.3
1
0.2
0.5
0.1
VOUT (V)
0
-0.5
0
-0.1
-1
-0.2
-1.5
-0.3
-2
-0.4
-2.5
-0.5
TIME (2 ns/div)
TIME (2 ns/div)
Figure 7.
Figure 8.
Harmonic Distortion
vs.
Frequency
Harmonic Distortion
vs.
Load
-45
VOUT = 2 VPP
-30
f = 10 MHz
-40
2
-50
HARMONIC DISTORTION (dBc)
HARMONIC DISTORTION (dBc)
-20
nd
-60
-70
-80
-90
rd
3
-100
-110
-55
VOUT = 2 VPP
-65
2
-85
-95
3
1
10
FREQUENCY (MHz)
0
100
200
400
600
800
1000
LOAD RESISTANCE (:)
Figure 9.
Figure 10.
Harmonic Distortion
vs.
Output Voltage
DG/DP
0.025
-45
2
-55
nd
0.2
0.025
f = 4.43 MHz
0.2
RL = 150:
0.015
-65
0.015
0.01
0.01
DG (%)
HARMONIC DISTORTION (dBc)
rd
-105
-115
-120
-75
-85
3
rd
0.005
DP
0.005
DG
0
0
-0.005
-0.005
-0.01
-95
-0.01
-0.015
-0.015
f = 10 MHz
-105
-0.02
-0.02
RL = 100:
-0.025
-0.025
-115
0
1
2
3
4
5
6
7
-1 -0.75 -0.5 -0.25
0
0.25 0.5 0.75
1
VOUT (VDC)
OUTPUT VOLTAGE PEAK TO PEAK
Figure 11.
6
nd
-75
DP (°)
VOUT (V)
Large Signal Pulse Response
2.5
Figure 12.
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Typical Performance Characteristics (continued)
(TA = 25°C, VS = ±5V, RL = 100Ω, AV = +2, VOUT = 0.5 VPP; Unless Specified).
DC Errors
vs.
Temperature (A Typical Unit,
90
9
80
8
-5
7
-6
6
-7
5
-8
4
-9
OFFSET VOLTAGE (mV)
PSRR (dB)
)
10
PSRR -
70
60
50
40
PSRR +
30
20
-3
-4
IBN
3
VOS
2
10
10k
100k
1M
10M
100M
0
-75 -50 -25
1G
-10
-11
-12
1
0
FREQUENCY (Hz)
-13
0
25
50 75 100 125 150
TEMPERATURE (°C)
Figure 13.
Figure 14.
Disable Timing
Disable Output Glitch
1V
20 mV
0V
VO
VO
(1)
100
BIAS CURRENT (PA)
PSRR
vs.
Frequency
-1V
0V
-20 mV
3V
3V
2V
2V
DIS
DIS
-40 mV
1V
0V
0V
TIME (10 ns/div)
TIME (10 ns/div)
Figure 15.
(1)
1V
Figure 16.
Negative current implies current flowing out of the device.
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APPLICATION INFORMATION
+5V
+5V
6.8 µF
6.8 µF
.01 µF
VIN
RIN
VIN
6 CPOS
3
CSS
0.1 µF
.01 µF
+
1
LMH6704
4
-
VOUT
RIN
6 CPOS
3
CSS
0.1 µF
NC
2 CNEG
+
LMH6704
4
.01 µF
-
1
VOUT
2 CNEG
.01 µF
6.8 µF
6.8 µF
-5V
-5V
Figure 17. Recommended Gain of +2 Circuit
Figure 18. Recommended Gain of +1 Circuit
+5V
6.8 µF
.01 µF
6 CPOS
3
+
CSS
LMH6704
0.1 µF
VIN
4
RIN
-
1
VOUT
2 CNEG
.01 µF
6.8 µF
-5V
Figure 19. Recommended Gain of −1 Circuit
GENERAL INFORMATION
The LMH6704 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 LMH6704 offers excellent AC performance
while simplifying board layout and minimizing the affects of layout related parasitic components. The LMH6704
has no internal ground reference so single or split supply configurations are both equally useful.
SETTING THE CLOSED LOOP GAIN
The LMH6704 is a current feedback amplifier with on-chip RF = RG = 465Ω. 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.
GAIN AV
Input Connections
Non-Inverting (Pin 3, SOT-23)
Inverting (Pin 4, SOT-23)
−1 V/V
Ground
Input Signal
+1 V/V
Input Signal
NC (Open)
+2 V/V
Input Signal
Ground
The gain accuracy of the LMH6704 is accurate over temperature to within ±1%. The internal gain setting
resistors, RFand RG, match very well. The LMH6704 architecture takes advantage of the fact that the internal
gain setting resistors track each other well over a wide range of temperature and process variation to keep the
overall gain constant, despite the fact that the individual resistors have nominal temperature drifts. Therefore,
using external resistors in series with RG to change the gain will result in poor gain accuracy over temperature.
8
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+5V
6.8 µF
.01 µF
VIN
6 CPOS
3
CSS
0.1 µF
RIN
+
1
LMH6704
4
-
VOUT
2 CNEG
.01 µF
6.8 µF
-5V
Figure 20. Alternate Unity Gain Configuration
UNITY GAIN COMPENSATION
With a current feedback Selectable Gain Buffer like the LMH6704, the feedback resistor is a compromise
between the value needed for stability at unity gain and the optimized value needed at a gain of two. In standard
open-loop current feedback operational amplifiers the feedback resistor, RF, is external and its value can be
adjusted to match the required gain. Since the feedback resistor is integrated in the LMH6704, it is not possible
to adjust it’s value. However, we can employ the circuit shown in Figure 20. This circuit modifies the noise gain of
the amplifier to eliminate the peaking associated with using the circuit shown in Figure 18. The frequency
response is shown in Figure 21. The decreased peaking does come at a price as the output referred voltage
noise density increases by a factor of 1.1.
4
STANDARD CIRCUIT
(FIGURE 2)
3
2
GAIN (dB)
1
0
-1
ALTERNATE CIRCUIT
(FIGURE 4)
-2
-3
-4
-5
-6
1
10
100
1000
FREQUENCY (MHz)
Figure 21. Unity Gain Frequency Response
OUTPUT VOLTAGE NOISE
Open-loop operational amplifiers specify three input referred noise parameters: input voltage noise, non-inverting
input current noise, and inverting input current noise. These specifications are used to calculate the total voltage
noise produced at the output of the amplifier. The LMH6704 is a closed loop amplifier with internal resistors, thus
only the non-inverting input current noise flows through external components. All other noise sources are internal
to the part. There are four possible values for the noise at the output depending on the gain configuration as
shown in Table 2. For more information on calculating noise in current feedback amplifiers see Application Notes
OA-12 and AN104 available at www.ti.com.
The total noise voltage at the output can be calculated using Equation 1:
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EO =
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(4kTRSOURCE + (IBN * RSOURCE)2) * GN2 + (OUTPUT REFERRED NOISE VOLTAGE)2, Where
GN = Noise Gain and 4kT = 16E-21 Joules @ Room Temperature
(1)
For example, if an AV = +2 configuration is used with a source impedance of 37.5Ω (parallel combination of 75Ω
source and 75Ω termination impedances), where “IBN” is 18.5pA/√Hz and the output referred voltage noise
(excluding non-inverting input noise current) can be found in Table 2. The total noise (EO) at the output can be
calculated as:
EO =
2
2
2
(16E-21*37.5 + (18.5 pA*37.5) )*2 + (10.5 nV) = 10.6 nV/
Hz
(2)
Table 2. Measured Output Noise Voltage (1)
(1)
Gain (AV)
Output Referred Voltage Noise
(nV/√Hz), excluding non-inverting noise current
+2
10.5
+1
9.3
+1, alternate method shown in Figure 20
10.5
-1
10.5
Note: f ≥ 100 kHz
ENABLE/DISABLE
PIN 6
VS
20 k:
SUPPLY
MID-POINT
BIAS CIRCUITRY
+
20 k: PULL-UP
RESISTOR
PIN 5
+
Q2
-
VS - V S
2
Q1
DIS
20 k:
I TAIL
PIN 2
VS
-
NOTE: PINS 2, 5, 6 ARE EXTERNAL
Figure 22. DIS Pin Simplified Schematic
The LMH6704 has a TTL logic compatible disable function. Apply a logic low (2.0V), or let the pin float and the LMH6704 is enabled. Voltage, not
current, at the Disable pin (DS) determines the enable/disable state. Care must be exercised to prevent the
disable pin voltage from going more than .8V below the midpoint of the supply voltages (0V with split supplies,
V+/2 with single supply biasing). Doing so could cause transistor Q1 to Zener resulting in damage to the disable
circuit (See Figure 22 or the simplified internal schematic diagram using SOT-23 package pin numbers). The
core amplifier is unaffected by this, but the disable operation could become permanently slower as a result.
Disabled, the LMH6704 inputs and output become high impedances. While disabled the LMH6704 quiescent
current is approximately 250 µA. Because of the pull up resistor on the disable circuit, the ICC and IEE currents
(positive and negative supply currents respectively) are not balanced in the disabled state. The positive supply
current (ICC) is approximately 350 µA while the negative supply current (IEE) is only 250 µA. The remaining IEE
current of 100 µA flows through the disable pin.
The disable function can be used to create analog switches or multiplexers. Implement a single analog switch
with one LMH6704 positioned between an input and output. Create an analog multiplexer with several
LMH6704’s. Use the circuit shown in for multiplexer applications because there is no RG to shunt signals to
ground.
10
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EVALUATION BOARDS
Texas Instruments provides the following evaluation boards as a guide for high frequency layout and as an aid in
device testing and characterization. Many of the data sheet plots were measured with these boards.
Device
Package
Evaluation Board Part Number
LMH6704MA
SOIC-8
CLC730227
LMH6704MF
SOT23-6
CLC730216
DRIVING CAPACITIVE LOADS
Capacitive output loading applications will benefit from the use of a series output resistor RISO. Figure 23 shows
the use of a series output resistor, RISO, 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 chart “Suggested RISO vs. Cap Load” gives a recommended value for selecting a series output resistor for
mitigating capacitive loads. The values suggested in the charts are selected for 0.5 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 RISO can be reduced slightly
from the recommended values.
VIN
RIN
50:
RISO
50:
+
+
VOUT
-
-
CL
10 pF
RL
1 k:
Figure 23. Decoupling Capacitive Loads
LAYOUT CONSIDERATIONS
Whenever questions about layout arise, use the evaluation board as a guide. To reduce parasitic capacitances
ground and power planes should be removed near the input and output pins. 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. In Figure 17, Figure 18, and Figure 19 CSS is
optional, but is recommended for best second order harmonic distortion. Another option to using CSS is to use
pairs of 0.01 μF and 0.1 µF ceramic capacitors for each supply bypass.
6.8 PF
C2
.01 PF
C1
VIN
+
RIN
75:
-
+
VOUT
-
ROUT
75:
.01 PF
C3
6.8 PF
C4
Figure 24. Typical Video Application
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Product Folder Links: LMH6704
11
LMH6704
SNOSAD0C – FEBRUARY 2005 – REVISED MARCH 2013
www.ti.com
VIDEO PERFORMANCE
The LMH6704 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
with DG of 0.02% and DP of 0.02°. 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.
POWER DISSIPATION
Follow these steps to determine the Maximum power dissipation for the LMH6704:
1. Calculate the quiescent (no-load) power:
PAMP = ICC* (VS)
+
(3)
−
where VS = V - V
2. Calculate the RMS power dissipated in the output stage:
PD (rms) = rms ((VS - VOUT) x IOUT)
(4)
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
(5)
The maximum power that the LMH6704, package can dissipate at a given temperature can be derived with the
following equation:
PMAX = (150° – TAMB)/ θJA, where TAMB = Ambient temperature (°C) and θJA = Thermal resistance, from junction
to ambient, for a given package (°C/W). For the SOT-23 package θJA is 187°C/W.
ESD PROTECTION
The LMH6704 is protected against electrostatic discharge (ESD) on all pins. The LMH6704 will survive 2000V
Human Body model and 200V Machine model events. Input and Output pins have ESD diodes to either supply
pin (V+ and V−) which are reverse biased and essentially have no effect under most normal operating conditions.
There are occasions, however, when the ESD diodes will be evident. If the LMH6704 is driven by a large signal
while the device is powered down, the ESD diodes might enter forward operating region and 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 inadvertently power up the LMH6704 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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Product Folder Links: LMH6704
LMH6704
www.ti.com
SNOSAD0C – FEBRUARY 2005 – REVISED MARCH 2013
REVISION HISTORY
Changes from Revision B (March 2013) to Revision C
•
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 12
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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)
LMH6704MA/NOPB
ACTIVE
SOIC
D
8
95
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
LMH67
04MA
LMH6704MF/NOPB
ACTIVE
SOT-23
DBV
6
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
B07A
LMH6704MFX/NOPB
ACTIVE
SOT-23
DBV
6
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 85
B07A
(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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