NSC LMH6655MMX

LMH6654/55
Single/Dual Low Power, 250 MHz, Low Noise Amplifiers
General Description
Features
The LMH6654/55 single and dual high speed, voltage feedback amplifiers are designed to have unity-gain stable operation with a bandwidth of 250MHz. They operate from
± 2.5V to ± 6V and each channel consumes only 4.5mA. The
amplifiers feature very low voltage noise and wide output
swing to maximize signal-to-noise ratio.
The LMH6654/55 have a true single supply capability with
input common mode voltage range extending 150 mV below
negative rail and within 1.3V of the positive rail.
LMH6654/55 high speed and low power combination make
these products an ideal choice for many portable, high
speed application where power is at a premium.
The LMH6654 is packaged in SOT23-5 and SOIC-8. The
LMH6655 is packaged in MSOP-8 and SOIC-8.
The LMH6654/55 are built on National’s Advance VIP10™
(Vertically Integrated PNP) complementary bipolar process.
(VS = ± 5V, TJ = 25˚C, Typical values unless specified).
n Voltage feedback architecture
n Unity gain bandwidth
250MHz
± 2.5V to ± 6V
n Supply voltage range
n Slew rate
200V/µsec
n Supply current
4.5mA/channel
n Input common mode voltage
−5.15V to +3.7V
n Output voltage swing (RL = 100Ω)
−3.6V to 3.4V
n Input voltage noise
4.5nV/
n Input current noise
1.7pA/
n Settling Time to 0.01%
25ns
Applications
n
n
n
n
n
n
ADC drivers
Consumer video
Active filters
Pulse delay circuits
xDSL receiver
Pre-amps
Typical Performance Characteristics
Input Voltage Noise vs. Frequency
20016560
© 2001 National Semiconductor Corporation
DS200165
Closed Loop Gain vs. Frequency
20016558
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LMH6654/55 Single/Dual Low Power, 250 MHz, Low Noise Amplifiers
August 2001
LMH6654/55
Absolute Maximum Ratings
(Note 1)
Soldering Information
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
ESD Tolerance (Note 2)
Human Body Model
200V
± 1.2V
VIN Differential
Output Short Circuit Duration
± 2.5V to ± 6.0V
Junction Temperature Range
−40˚C to +85˚C
8-Pin SOIC
13.2V
Storage Temperature Range
−65˚C to +150˚C
Junction Temperature (Note 4)
(Note 1)
Supply Voltage (V+ - V−)
V+ +0.5V, V− −0.5V
Voltage at Input pins
260˚C
Thermal Resistance (θJA)
(Note 3)
Supply Voltage (V+ − V−)
235˚C
Wave Soldering (10 sec.)
Operating Ratings
2kV
Machine Model
Infrared or Convection (20 sec.)
172˚C/W
8-Pin MSOP
235˚C/W
5-Pin SOT-23
265˚C/W
+150˚C
± 5V Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = +5V, V− = −5V, VCM = 0V, AV = +1, RF = 25Ω for gain =
+1, RF = 402Ω for gain = ≥ +2, and RL = 100Ω. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Units
Dynamic Performance
fCL
GBWP
Close Loop Bandwidth
AV = +1
250
AV = +2
130
AV = +5
52
MHz
AV = +10
26
Gain Bandwidth Product
AV ≥ +5
260
MHz
Bandwidth for 0.1dB Flatness
AV +1
18
MHz
φm
Phase Margin
SR
Slew Rate (Note 8)
TS
Settling Time
0.01%
tr
tf
50
deg
AV = +1, VIN = 2VPP
200
V/µs
AV = +1, 2V Step
25
ns
15
ns
Rise Time
AV = +1, 0.2V Step
1.4
ns
Fall Time
AV = +1, 0.2V Step
1.2
ns
0.1%
Distortion and Noise Response
en
Input Referred Voltage Noise
f ≥ 0.1 MHz
4.5
nV/
in
Input-Referred Current Noise
f ≥ 0.1 MHz
1.7
pA/
Second Harmonic Distortion
AV = +1, f = 5MHz
−80
Third Harmonic Distortion
VO = 2VPP, RL = 100Ω
−85
Xt
Crosstalk (for LMH6655 only)
Input Referred, 5MHz,
Channel-to-Channel
−80
dB
DG
Differential Gain
AV = +2, NTSC, RL = 150Ω
0.01
%
DP
Differential Phase
AV = +2, NTSC, RL = 150Ω
0.025
deg
dBc
Input Characteristics
VOS
Input Offset Voltage
VCM = 0V
−3
−4
±1
3
4
mV
TC VOS
Input Offset Average Drift
VCM = 0V (Note 7)
6
IB
Input Bias Current
VCM = 0V
5
12
18
µA
IOS
Input Offset Current
VCM = 0V
0.3
1
2
µA
RIN
Input Resistance
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−1
−2
µV/˚C
Common- Mode
4
MΩ
Differential Mode
20
kΩ
2
(Continued)
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = +5V, V− = −5V, VCM = 0V, AV = +1, RF = 25Ω for gain =
+1, RF = 402Ω for gain = ≥ +2, and RL = 100Ω. Boldface limits apply at the temperature extremes.
Symbol
CIN
Parameter
Input Capacitance
Conditions
Min
(Note 6)
Typ
(Note 5)
Common- Mode
1.8
Differential Mode
1
CMRR
Common Mode Rejection Ration
Input Referred,
VCM = 0V to −5V
CMVR
Input Common- Mode Voltage Range
CMRR ≥ 50dB
70
68
Max
(Note 6)
pF
90
−5.15
3.5
3.7
VO = 4VPP, RL = 100Ω
60
58
67
Output Swing High
No Load
3.4
3.2
3.6
Output Swing Low
No Load
Output Swing High
RL = 100Ω
Output Swing Low
RL = 100Ω
Short Circuit Current (Note 3)
Sourcing, VO = 0V
∆VIN = 200mV
145
130
280
Sinking, VO = 0V
∆VIN = 200mV
100
80
185
Units
dB
−5.0
V
Transfer Characteristics
AVOL
Large Signal Voltage Gain
dB
Output Characteristics
VO
ISC
IOUT
RO
Output Current
Output Resistance
−3.9
3.2
3.0
−3.7
−3.5
V
3.4
−3.6
−3.4
−3.2
mA
Sourcing, VO = +3V
80
Sinking, VO = −3V
120
AV = +1, f < 100kHz
0.08
Ω
76
dB
mA
Power Supply
PSRR
Power Supply Rejection Ratio
IS
Supply Current (per channel)
Input Referred ,
VS = ± 5V to ± 6V
60
4.5
6
7
mA
5V Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = +5V, V− = −0V, VCM = 2.5V, AV = +1, RF = 25Ω for gain
= +1, RF = 402Ω for gain = ≥ +2, and RL = 100Ω to V+/2. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Units
Dynamic Performance
fCL
GBWP
φm
Close Loop Bandwidth
AV = +1
230
AV = +2
120
AV = +5
50
MHz
AV = +10
25
Gain Bandwidth Product
AV ≥ +5
250
MHz
Bandwidth for 0.1dB Flatness
AV = +1
17
MHz
48
deg
Phase Margin
SR
Slew Rate (Note 8)
AV = +1, VIN = 2VPP
190
V/µs
TS
Settling Time
0.01%
AV = +1, 2V Step
30
ns
20
ns
0.1%
3
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LMH6654/55
± 5V Electrical Characteristics
LMH6654/55
5V Electrical Characteristics
(Continued)
Unless otherwise specified, all limits guaranteed for TJ = 25˚C, V+ = +5V, V− = −0V, VCM = 2.5V, AV = +1, RF = 25Ω for gain
= +1, RF = 402Ω for gain = ≥ +2, and RL = 100Ω to V+/2. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Units
tr
Rise Time
AV = +1, 0.2V Step
1.5
ns
tf
Fall Time
AV = +1, 0.2V Step
1.35
ns
Distortion and Noise Response
en
Input Referred Voltage Noise
f ≥ 0.1MHz
4.5
nV/
in
Input Referred Current Noise
f ≥ 0.1 MHz
1.7
pA/
Second Harmonic Distortion
AV = +1, f = 5MHz
−65
Third Harmonic Distortion
VO = 2VPP, RL = 100Ω
−70
Crosstalk (for LMH6655 only)
Input Referred, 5MHz
−78
Xt
dBc
dB
Input Characteristics
VOS
Input Offset Voltage
VCM = 2.5V
−5
−6.5
±2
5
6.5
mV
TC VOS
Input Offset Average Drift
VCM = 2.5V (Note 7)
6
IB
Input Bias Current
VCM = 2.5V
6
12
18
µA
IOS
Input Offset Current
VCM = 2.5V
0.5
2
3
µA
RIN
Input Resistance
CIN
Input Capacitance
−2
−3
µV/˚C
Common- Mode
4
MΩ
Differential Mode
20
kΩ
Common- Mode
1.8
pF
Differential Mode
1
CMRR
Common Mode Rejection Ration
Input Referred,
VCM = 0V to −2.5V
CMVR
Input Common Mode Voltage Range
CMRR ≥ 50dB
70
68
90
−0.15
3.5
3.7
VO = 1.6VPP, RL = 100Ω
58
55
64
Output Swing High
No Load
3.6
3.4
3.75
Output Swing Low
No Load
Output Swing High
RL = 100Ω
Output Swing Low
RL = 100Ω
Short Circuit Current (Note 3)
Sourcing , VO = 2.5V
∆VIN = 200mV
90
80
170
Sinking, VO = 2.5V
∆VIN = 200mV
70
60
140
dB
0
V
Transfer Characteristics
AVOL
Large Signal Voltage Gain
dB
Output Characteristics
VO
ISC
IOUT
RO
Output Current
Output Resistance
0.9
3.5
3.35
1.1
1.3
V
3.70
1
1.3
1.45
mA
Sourcing, VO = +3.5V
30
Sinking, VO = 1.5V
60
AV = +1, f < 100kHz
.08
Ω
75
dB
mA
Power Supply
PSRR
Power Supply Rejection Ratio
IS
Supply Current (per channel)
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Input Referred ,
VS = ± 2.5V to ± 3V
60
4.5
4
6
7
mA
(Continued)
Note 1: 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 guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics Table.
Note 2: Human body model, 1.5kΩ in series with 100pF. Machine model: 0Ω in series with 100pF.
Note 3: Continuous short circuit operation at elevated ambient temperature can result in exceeding the maximum allowed junction temperature at 150˚C.
Note 4: The maximum power dissipation is a function of TJ(MAX), θJA and TA. 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.
Note 5: Typical Values represent the most likely parametric norm.
Note 6: All limits are guaranteed by testing or statistical analysis.
Note 7: Offset voltage average drift is determined by dividing the change in VOS at temperature extremes into the total temperature change.
Note 8: Slew rate is the slower of the rising and falling slew rates. Slew rate is rate of change from 10% to 90% of output voltage step.
Typical Performance Characteristics
TJ = 25˚C, V+ = ± 5V, V− = −5, RF = 25Ω for gain = +1, RF =
402Ω and for gain ≥ +2, and RL = 100Ω, unless otherwise specified.
Closed Loop Bandwidth (G = +1)
Closed Loop Bandwidth (G = +2)
20016509
20016510
Closed Loop Bandwidth (G = +5)
Closed Loop Bandwidth (G = +10)
20016511
20016512
5
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LMH6654/55
5V Electrical Characteristics
LMH6654/55
Typical Performance Characteristics
TJ = 25˚C, V+ = ± 5V, V− = −5, RF = 25Ω for gain = +1, RF =
402Ω and for gain ≥ +2, and RL = 100Ω, unless otherwise specified. (Continued)
Supply Current per Channel vs. Supply Voltage
Supply Current per Channel vs. Temperature
20016535
20016548
Offset Voltage vs. Supply Voltage (VCM = 0V)
Offset Voltage vs. Common Mode
20016532
20016549
Offset Voltage vs. Common Mode
Bias Current and Offset Voltage vs. Temperature
20016551
20016539
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6
TJ = 25˚C, V+ = ± 5V, V− = −5, RF = 25Ω for gain = +1, RF =
402Ω and for gain ≥ +2, and RL = 100Ω, unless otherwise specified. (Continued)
Bias Current vs. Common Mode Voltage
AOL, PSRR and CMRR vs. Temperature
20016550
20016537
Inverting Large Signal Pulse Response (VS = ± 5V)
Inverting Large Signal Pulse Response (VS = 5V)
20016502
20016504
Non-Inverting Large Signal Pulse Response (VS = ± 5V)
Non-Inverting Large Signal Pulse Response (VS = 5V)
20016506
20016508
7
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LMH6654/55
Typical Performance Characteristics
LMH6654/55
Typical Performance Characteristics
TJ = 25˚C, V+ = ± 5V, V− = −5, RF = 25Ω for gain = +1, RF =
402Ω and for gain ≥ +2, and RL = 100Ω, unless otherwise specified. (Continued)
Non-Inverting Small Signal Pulse Response (VS = ± 5V)
Non-Inverting Small Signal Pulse Response (VS = 5V)
20016505
20016507
Inverting Small Signal Pulse Response (VS = ± 5V)
Inverting Small Signal Pulse Response (VS = 5V)
20016501
20016503
Input Voltage and Current Noise vs. Frequency
(VS = ± 5V)
Input Voltage and Current Noise vs. Frequency (VS = 5V)
20016513
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20016514
8
TJ = 25˚C, V+ = ± 5V, V− = −5, RF = 25Ω for gain = +1, RF =
402Ω and for gain ≥ +2, and RL = 100Ω, unless otherwise specified. (Continued)
Harmonic Distortion vs. Frequency
G = +1, VO = 2VPP, VS = 5V
Harmonic Distortion vs. Frequency
G = +1, VO = 2VPP, VS = ± 5V
20016517
20016518
Harmonic Distortion vs. Temperature
VS = 5V, f = 5MHz, VO = 2VPP
Harmonic Distortion vs. Temperature
VS = ± 5V, f = 5MHz, VO = 2VPP
20016529
20016528
Harmonic Distortion vs. Gain
VS = 5V, f = 5MHz, VO = 2VPP
Harmonic Distortion vs. Gain
VS = ± 5V, f = 5MHz, VO = 2VPP
20016531
20016530
9
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LMH6654/55
Typical Performance Characteristics
LMH6654/55
Typical Performance Characteristics
TJ = 25˚C, V+ = ± 5V, V− = −5, RF = 25Ω for gain = +1, RF =
402Ω and for gain ≥ +2, and RL = 100Ω, unless otherwise specified. (Continued)
Harmonic Distortion vs. Output Swing
(G = +2, VS = 5V, f = 5MHz)
Harmonic Distortion vs. Output Swing
(G = +2, VS = ± 5V, f = 5MHz)
20016559
20016522
PSRR vs. Frequency
CMRR vs. Frequency
20016564
20016516
Output Sinking Current
Output Sourcing Current
20016546
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20016547
10
TJ = 25˚C, V+ = ± 5V, V− = −5, RF = 25Ω for gain = +1, RF =
402Ω and for gain ≥ +2, and RL = 100Ω, unless otherwise specified. (Continued)
CrossTalk vs. Frequency (LMH6655 only)
CrossTalk vs. Frequency (LMH6655 only)
20016561
20016562
Isolation Resistance vs. Capacitive Load
Open Loop Gain and Phase vs. Frequency
20016563
20016527
11
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LMH6654/55
Typical Performance Characteristics
LMH6654/55
Connection Diagrams
LMH6654 in SOIC
LMH6654 in SOT23-5
LMH6655 in SOIC and MSOP
20016520
20016521
Top View
Top View
20016519
Top View
Ordering Information
Package
Part Number
Package Marking
Transport Media
NSC Drawing
8-Pin SOIC
LMH6654MA
LMH6654MA
95 Units Rails
M08A
LMH6654MAX
LMH6655MA
2.5k Units Tape and Reel
LMH6655MA
LMH6655MAX
5-Pin SOT23-5
LMH6654MF
A66A
1k Units Tape and Reel
LMH6654MFX
8-Pin MSOP
LMH6655MM
MF05A
3K Units Tape and Reel
A67A
1k Units Tape and Reel
LMH6655MMX
MUA08A
3.5k Units Tape and Reel
should be connected in parallel, to supply current for fast
large signal changes at the output.
Application Information
General Information
The LMH6654 single and LMH6655 dual high speed, voltage
feedback amplifiers are manufactured on National Semiconductor’s new VIP10 (Vertically Integrated PNP) complementary bipolar process. These amplifiers can operate from
± 2.5V to ± 6V power supply. They offer low supply current,
wide bandwidth, very low voltage noise and large output
swing. Many of the typical performance plots found in the
datasheet can be reproduced if 50Ω coax and 50Ω RIN/ROUT
resistors are used.
Circuit Layout Consideration
With all high frequency devices, board layouts with stray
capacitance have a strong influence on the AC performance.
The LMH6654/55 are not exception and the inverting input
and output pins are particularly sensitive to the coupling of
parasitic capacitance to AC ground. Parasitic capacitances
on the inverting input and output nodes to ground could
cause frequency response peaking and possible circuit oscillation. Therefore, the power supply, ground traces and
ground plan should be placed away from the inverting input
and output pins. Also, it is very important to keep the parasitic capacitance across the feedback to an absolute minimum.
The PCB should have a ground plane covering all unused
portion of the component side of the board to provide a low
impedance path. All trace lengths should be minimized to
reduce series inductance.
Supply bypassing is required for the amplifiers performance.
The bypass capacitors provide a low impedance return current path at the supply pins. They also provide high frequency filtering on the power supply traces. It is recommended that a ceramic decoupling capacitor 0.1µF chip
should be placed with one end connected to the ground
plane and the other side as close as possible to the power
pins. An additional 10µF tantalum electrolytic capacitor
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95 Units Rails
2.5k Units Tape and Reel
20016541
FIGURE 1.
Evaluation Boards
National provides the following evaluation boards as a guide
for high frequency layout and as an aid in device testing and
characterization.
12
Device
Package
Evalulation
Board PN
LMH6654MF
SOT23-5
CLC730068
LMH6654MA
8-Pin SOIC
CLC730027
LMH6655MA
8-Pin SOIC
CLC730036
LMH6655MM
8-Pin MSOP
CLC730123
LMH6654/55
Application Information
(Continued)
The free evaluation board are shipped automatically when a
device sample request is placed with National Semiconductor.
The CLC730027 datasheet also contains tables of recommended components to evaluate several of National’s high
speed amplifiers. This table for the LMH6654 is illustrated
below. Refer to the evaluation board datasheet for schematics and further information.
Components Needed to Evaluate the LMH6654 on the
Evaluation Board:
•
•
•
20016540
RfRg use the datasheet to select values.
FIGURE 2.
RIN, ROUT typically 50Ω (Refer to the Basic Operation
section of the evaluation board datasheet for details)
Components Selection and Feedback Resistor
It is important in high-speed applications to keep all component leads short since wires are inductive at high frequency.
For discrete components, choose carbon composition axially
leaded resistors and micro type capacitors. Surface mount
components are preferred over discrete components for
minimum inductive effect. Never use wire wound type resistors in high frequency applications.
Large values of feedback resistors can couple with parasitic
capacitance and cause undesired effects such as ringing or
oscillation in high-speed amplifiers. Keep resistors as low as
possible consistent with output loading consideration. For a
gain of 2 and higher, 402Ω feedback resistor used for the
typical performance plots gives optimal performance. For
unity gain follower, a 25Ω feedback resistor is recommended
rather than a direct short. This effectively reduces the Q of
what would otherwise be a parasitic inductance (the feedback wire) into the parasitic capacitance at the inverting
input.
Bias Current Cancellation
In order to cancel the bias current errors of the non-inverting
configuration, the parallel combination of the gain setting Rg
and feedback Rf resistors should equal the equivalent
source resistance Rseq as defined in Figure 3. Combining
this constraint with the non-inverting gain equation, allows
both Rf and Rg to be determined explicitly from the following
equations:
Rf = AVRseq and Rg = Rf/(AV−1)
Rf is an optional resistor for inverting again configurations
(select Rf to yield desired input impedance = Rg||Rf)
• C1, C2 use 0.1µF ceramic capacitors
• C3, C4 use 10µF tantalum capacitors
Components not used:
1. C5, C6, C7, C8
2. R1 thru R8
The evaluation boards are designed to accommodate dual
supplies. The board can be modified to provide single operation. For best performance;
1) do not connect the unused supply.
2) ground the unused supply pin.
power Dissipation
The package power dissipation should be taken into account
when operating at high ambient temperature and/or high
power dissipative conditions. In determining maximum operable temperature of the device, make sure the total power
dissipation of the device is considered; this power dissipated
in the device with a load connected to the output as well as
the nominal dissipation of the op amp.
Driving Capacitive Loads
Capacitive loads decrease the phase margin of all op amps.
The output impedance of a feedback amplifier becomes
inductive at high frequencies, creating a resonant circuit
when the load is capacitive. This can lead to overshoot,
ringing and oscillation. To eliminate oscillation or reduce
ringing, an isolation resistor can be placed as shown in
Figure 2 below. At frequencies above
For inverting configuration, bias current cancellation is accomplished by placing a resistor Rb on the non-inverting
input equal in value to the resistance seen by the inverting
input (Rf//(Rg+Rs). The additional noise contribution of Rb
can be minimized through the use of a shunt capacitor.
the load impedance of the Amplifier approaches RISO. The
desired performance depends on the value of the isolation
resistor. The isolation resistance vs. capacitance load graph
in the typical performance characteristics provides the
means for selection of the value of RS that provides ≤ 3dB
peaking in closed loop AV = 1 response. In general, the
bigger the isolation resistor, the more damped the pulse
response becomes. For initial evaluation, a 50Ω isolation
resistor is recommended.
13
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LMH6654/55
Application Information
(Continued)
20016544
FIGURE 5. Non-Inverting Amplifier Noise Model
(1)
Rf||Rg =Rseq for bias current cancellation. Figure 6 illustrates
the equivalent noise model using this assumption. The total
equivalent output voltage noise (eno) is eni * AV.
20016542
FIGURE 3. Non-Inverting Amplifier Configuration
20016545
FIGURE 6. Noise Model with Rf||Rg = Rseq
(2)
If bias current cancellation is not a requirement, then Rf||Rg
does not need to equal Rseq. In this case, according to
Equation 1, RfRg should be as low as possible in order to
minimize noise. Results similar to Equation 1 are obtained
for the inverting configuration on Figure 2 if Rseq is replaced
by Rb and Rg is replaced by Rg + Rs. With these substitutions, Equation 1 will yield an eni referred to the non-inverting
input. Referring to eni to the inverting input is easily accomplished by multiplying eni by the ration of non-inverting to
inverting gains.
Noise Figure
Noise Figure (NF) is a measure of the noise degradation
caused by an amplifier.
20016543
FIGURE 4. Inverting Amplifier Configuration
Total Input Noise vs. Source Resistance
The noise model for the non-inverting amplifier configuration
showing all noise sources is described in Figure 5. In addition to the intrinsic input voltage noise (en) and current noise
(in = in+ = in−) sources, there also exits thermal voltage noise
associated with each of the external resistors.
Equation 1 provides the general form for total equivalent
input voltage noise density (eni). Equation 2 is a simplification of Equation 1 that assumes
(3)
The noise figure formula is shown is Equation 3. The addition of a terminating resistor RT, reduces the external thermal noise but increases the resulting NF.
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14
LMH6654/55
Application Information
(Continued)
The NF is increased because the RT reduces the input signal
amplitude thus reducing the input SNR.
(4)
The noise figure is related to the equivalent source resistance (Rseq) and the parallel combination of Rf and Rg. To minimize noise
figure, the following steps are recommended:
1. Minimize Rf||Rg
2. Choose the Optimum Rs (ROPT)
ROPT is the point at which the NF curve reaches a minimum and is approximated by:
ROPT ≈ (en/in)
15
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LMH6654/55
Physical Dimensions
inches (millimeters) unless otherwise noted
8-Pin SOIC
NS Package Number M08A
5-Pin SOT23
NS Package Number MF05A
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16
LMH6654/55 Single/Dual Low Power, 250 MHz, Low Noise Amplifiers
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
8-Pin MSOP
NS Package Number MUA08A
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and
whose failure to perform when properly used in
accordance with instructions for use provided in the
labeling, can be reasonably expected to result in a
significant injury to the user.
National Semiconductor
Corporation
Americas
Email: [email protected]
www.national.com
National Semiconductor
Europe
Fax: +49 (0) 180-530 85 86
Email: [email protected]
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +44 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
2. A critical component is any component of a life
support device or system whose failure to perform
can be reasonably expected to cause the failure of
the life support device or system, or to affect its
safety or effectiveness.
National Semiconductor
Asia Pacific Customer
Response Group
Tel: 65-2544466
Fax: 65-2504466
Email: [email protected]
National Semiconductor
Japan Ltd.
Tel: 81-3-5639-7560
Fax: 81-3-5639-7507
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.