LMH6503
Wideband, Low Power, Linear Variable Gain Amplifier
LMH6503 Wideband, Low Power, Linear Variable Gain Amplifier
June 2004
General Description
The LMH™6503 is a wideband DC coupled differential input
voltage controlled gain stage followed by a high-speed current feedback Op Amp which can directly drive a low impedance load. Gain adjustment range is more than 70dB for up
to 10MHz.
Maximum gain is set by external components and the gain
can be reduced all the way to cut-off. Power consumption is
370mW with a speed of 135MHz . Output referred DC offset
voltage is less than 350mV over the entire gain control
voltage range. Device-to-device Gain matching is within
0.7dB at maximum gain. Furthermore, gain at any V
tested and the tolerance is guaranteed. The output current
feedback Op Amp allows high frequency large signals (Slew
Rate = 1800V/µs) and can also drive heavy load current
(75mA). Differential inputs allow common mode rejection in
low level amplification or in applications where signals are
carried over relatively long wires. For single ended operation, the unused input can easily be tied to ground (or to a
virtual half-supply in single supply application). Inverting or
non-inverting gains could be obtained by choosing one input
polarity or the other.
To further increase versatility when used in a single supply
application, gain control range is set to be from −1V to +1V
relative to pin 11 potential (ground pin). In single supply
operation, this ground pin is tied to a "virtual" half supply.
Gain control pin has high input impedance to simplify its
drive requirement. Gain control is linear in V/V throughout
the gain adjustment range. Maximum gain can be set to be
anywhere between 1V/V to 100V/V or higher. For linear in dB
gain control applications, see LMH6502 datasheet.
The LMH6503 is available in the SOIC-14 and TSSOP-14
package.
G
Features
VS=±5V, TA= 25˚C, RF=1kΩ,RG= 174Ω,RL= 100Ω,A
=A
n -3dB BW135MHz
n Gain control BW100MHz
n Adjustment range (typical over temp)70dB
n Gain matching (limit)
n Slew rate1800V/µs
n Supply current (no load)37mA
n Linear output current
n Output voltage (R
is
n Input voltage noise6.6nV/
n Input current noise2.4pA/
n THD (20MHz, RL= 100Ω,VO=2VPP)−57dBc
n Replacement for CLC522
= 10, Typical values unless specified.
V(MAX)
= 100Ω)
L
Applications
n Variable attenuator
n AGC
n Voltage controller filter
n Multiplier
±
0.7dB
±
75mA
±
V
3.2V
Typical Application
Gain vs. VGfor Various Temperature
LMH™is a trademark of National Semiconductor Corporation.
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
LMH6503
Distributors for availability and specifications.
Infrared or Convection (20 sec)235˚C
Wave Soldering (10 sec)260˚C
Storage Temperature Range−65˚C to +150˚C
Junction Temperature+150˚C
ESD Tolerance: (Note 4)
Human Body2KV
Machine Model200V
±
Input Current
V
Differential
IN
10mA
±
(V+−V−)
Output Current120mA (Note 3)
Supply Voltages (V
Voltage at Input/ Output pinsV
+-V−
)12.6V
+
+0.8V,V−- 0.8V
Operating Ratings (Note 1)
Supply Voltages (V
Temperature Range−40˚C to +85˚C
Thermal Resistance:θ
14-Pin SOIC138˚C/W45˚C/W
14-Pin TSSOP160˚C/W51˚C/W
+-V−
)5Vto12V
JA
θ
Soldering Information:
Electrical Characteristics(Note 2)
Unless otherwise specified, all limits guaranteed for TJ= 25˚C, VS=±5V, A
=±0.1V, RL= 100Ω,VG= +1V. Boldface limits apply at the temperature extremes.
_DIFF
SymbolParameterConditions
Frequency Domain Response
BW-3dB BandwidthV
GFGain FlatnessV
Att Range Flat Band (Relative to Max Gain)
Attenuation Range (Note 13)
BW
Gain Control BandwidthV
<
0.5
OUT
V
OUT
OUT
−1V
±
0.2dB Flatness, f<30MHZ20
±
0.1dB, f<30MHZ6.6
G
PP
<
<
<
V
0.5PP,A
0.5VPP,
<
1V,±0.2dB
G
= 10050
V(MAX)
= 0V (Note 11)100MHz
Control
PLLinear Phase DeviationDC to 60MHz1.6deg
G DelayGroup DelayDC to 130MHz2.6ns
CT (dB)Feed-throughV
= −1.2V, 30MHz (Output
G
Referred)
GRGain Adjustment Rangef<10MHz79
<
f
30MHz68
Time Domain Response
t
r,tf
Rise and Fall Time0.5V Step2.2ns
OS%Overshoot0.5V Step10%
SRSlew Rate4V Step (Note 5)1800V/µs
∆G RateGain Change RateV
= 0.3V, 10%−90% of final
IN
output
Distortion & Noise performance
HD22
HD33
THDTotal Harmonic Distortion2V
nd
Harmonic Distortion2VPP, 20MHz−60dBc
rd
Harmonic Distortion2VPP, 20MHz−61dBc
, 20MHz−57dBc
PP
En totTotal Equivalent Input Noise1MHz to 150MHz6.6nV/
I
n
Input Noise Current1MHz to 150MHz2.4pA/
DGDifferential Gainf = 4.43MHz, RL= 150Ω, Neg.
Sync
DPDifferential Phasef = 4.43MHz, R
= 150Ω, Neg.
L
Sync
= 10, VCM= 0V, RF=1kΩ,RG= 174Ω,V
V(MAX)
Min
(Note 6)
Typ
(Note 6)
Max
(Note 6)Units
135
40MHz
−48dB
4.6dB/ns
0.15%
0.22deg
JC
-
IN
MHz
MHz
dB
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Electrical Characteristics(Note 2) (Continued)
Unless otherwise specified, all limits guaranteed for TJ= 25˚C, VS=±5V, A
=±0.1V, RL= 100Ω,VG= +1V. Boldface limits apply at the temperature extremes.
_DIFF
SymbolParameterConditions
DC & Miscellaneous Performance
GACCUGain Accuracy (see Application
Notes)
G MatchGain Matching (see Application
Notes)
KGain Multiplier (see Application
Notes)
V
CM
V
IN_ DIFF
I
RG MAX
I
BIAS
TC
BIAS
I
OFF
TC I
R
IN
C
IN
IV
G
TC IV
RV
CV
V
OUT
R
OUT
I
OUT
V
O
OFFSET
G
G
Input Voltage RangePin3&6Common Mode,
Differential Input VoltageAcross pins3&6
RGCurrentPins4&5
Bias CurrentPins3&6(Note 7)1118
Bias Current DriftPin3&6(Note 8)100nA/˚C
Offset CurrentPin3&60.012.0
Offset Current Drift(Note 8)5nA/˚C
OFF
Input ResistancePin3&6750kΩ
Input CapacitancePin3&65pF
VGBias CurrentPin 2, VG= 1.4V(Note 7)45µA
VGBias DriftPin 2 (Note 8)20nA/˚C
G
VGInput ResistancePin 270KΩ
VGInput CapacitancePin 21.3pF
Output Voltage RangeRL= 100Ω
Output ImpedanceDC0.1Ω
Output CurrentV
Output Offset Voltage−1V<V
+PSRR+Power Supply Rejection Ratio
(see (Note 10))
−PSRR−Power Supply Rejection Ratio
(see (Note 10))
CMRRCommon Mode Rejection Ratio
(see (Note 9))
I
S
Supply CurrentRL= Open3750
V
=1.0V+0.25+0.9/−0.4
G
<
<
V
1V
G
<
−0.7V
V
= 1.0–
G
<
V
−0.7V
|CMRR|
<
V
1V
G
<
1V–+1.7/−1.1
G
<
<
V
1V–+4.0/−4.7
G
>
50dB (Note 9)
Pins3&6(Note 7),
=±2.5V
V
S
Open
R
L
±
4V from Rails
OUT
<
1V
G
Input Referred, 1V change,
VG= 1.4V
Input Referred, 1V change,
VG= 1.4V
Input Referred, V
<
−1.8V
R
V
CM
= Open, VS=±2.5V1220
L
<
G
1.8V
=1V
= 10, VCM= 0V, RF=1kΩ,RG= 174Ω,V
V(MAX)
Min
(Note 6)
Typ
(Note 6)
±
0.3+1.3/−1.5
±
0.4+4.4/−4.3
Max
(Note 6)Units
±
1.58
1.58
±
±
1.80
±
0.34
±
0.28
±
1.70
±
1.60
±
3.00
±
2.97
±
3.95
±
3.90
±
±
2.0
75
70
1.721.87
1.91
±
2.2V
±
0.37
±
2.30mA
310
±
3.20
±
4.05
±
90mA
±
80
±
±
−80−58
−56
−67−57
−51
−67dB
0.7
20
13
2.5
350
380
53
23
dB0V
dB0
V/V
V
µA
µA
V
mV
dB
dB
mA
-
IN
LMH6503
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Electrical Characteristics(Note 2) (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, see the Electrical Characteristics tables.
LMH6503
Note 2: 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 T
Note 3: The maximum output current (I
Note 4: Human body model: 1.5kΩ in series with 100pF. Machine model: 0Ω in series with 200pF.
Note 5: Slew Rate is the average of the rising and falling rates.
Note 6: Typical values represent the most likely parametric norm. Bold numbers refer to over temperature limits.
Note 7: Positive current correspondes to current flowing in the device.
Note 8: Drift determined by dividing the change in parameter distribution at temperature extremes by the total temperature change.
Note 9: CMRR definition: [|∆V
Note 10: +PSRR definition: [|∆V
offset shift subtracted out.
Note 11: Gain Control Frequency Response Schematic:
. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self-heating where T
J=TA
OUT
OUT
) is determined by device power dissipation limitations or value specified, whichever is lower.
OUT
/∆VCM|/AV] with 0.1V differential input voltage. ∆V
/∆V+|/AV], -PSRR definition: [|∆V
/∆V−|/AV] with 0.1V differential input voltage. ∆V
OUT
is the change in output voltage with offset shift subtracted out.
OUT
is the change in output voltage with
OUT
>
TA.
J
20073932
Note 12: Gain/Phase normalized to low frequency value at each AV.
Note 13: Flat Band Attenuation (Relative To Max Gain) Range Definition: Specified as the attenuation range from maximum which allows gain flatness specified
±
(either
0.2dB or±0.1dB), relative to A
±
0.2dB:10V/V down to 1V/V=20dB range
±
0.1dB:10V/V down to 4.7V/V=6.5dB range
gain. For example, for f<30MHz, here are the Flat Band Attenuation ranges: