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LMH6718
Dual, High Output, Programmable Gain Buffer
General Description
The LMH6718 is a dual, low cost high speed (130MHz)
buffer which features user programmable gains of +2, +1,
and -1V/V. The LMH6718 also has a new output stage that
delivers high output drive current (200mA), but consumes
minimal quiescent supply current (2.6mA/Amp) from a
5V
supply. Its current feedback architecture, fabricated in an
advanced complementary bipolar process, maintains consis-
tent performance over a wide range of signal levels, and has
a linear phase response up to one half of the -3dB frequency.
The LMH6718 offers 0.1dB gain flatness to 30MHz and
differential gain and phase errors of .04% and .03. These
features are ideal for professional and consumer video ap-
plications.
The LMH6718 offers superior dynamic performance with a
130MHz small-signal bandwidth, 600V/s slew rate and
4.2ns rise/fall times (2V
STEP
). The combination of low quies-
cent current, high output current drive, and high speed per-
formance makes the LMH6718 well suited for many battery
powered personal communication/computing systems. The
ability to drive low impedance, high capacitive loads, makes
the LMH6718 ideal for single ended cable applications. It
also drives low impedance loads with minimum distortion.
The LMH6718 will drive a 100
load with only -84/-84dBc
second/third harmonic distortion (A
V
= +2, V
OUT
= 2V
PP
, f =
1MHz). It is also optimized for driving high currents into
single-ended transformers and coils. When driving the input
of high resolution A/D converters, the LMH6718 provides
excellent -88/-98dBc second/third harmonic distortion (A
V
=
+2, V
OUT
= 2V
PP
, f = 1MHz, R
L
= 1k
) and fast settling time.
The LMH6718 is fabricated using National's VIP10
TM
com-
plimentary bipolar process.
Features
n
200mA output current
n
.04%, .03 differential gain, phase
n
5.2mA supply current for 2 amplifiers
n
130MHz bandwidth (A
V
= +2)
n
-88/-98dBc HD2/HD3 (1MHz)
n
16ns settling to 0.05%
n
600V/s slew rate
n
Nominal supply range
2.5V to
6V
n
Improved replacement for CLC5632
Applications
n
Video line driver
n
Coaxial cable driver
n
Twisted pair driver
n
Transformer/coil driver
n
High capacitive load driver
n
Portable/battery powered applications
n
A/D driver
n
I/Q Channel Amplifier
Connection Diagram
8-Pin SOIC
20040116
Top View
Maximum Output Voltage vs. Load
Resistance
20040164
January 2003
LMH6718
Dual,
High
Output,
Programmable
Gain
Buffer
2003 National Semiconductor Corporation
DS200401
www.national.com
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
ESD Tolerance (Note 5)
Human Body Model
2kV
Machine Model
200V
Supply Voltage
13.5
Output Current
(Note 3)
Common-Mode Input Voltage
V
+
- V
-
Maximum Junction Temperature
+150C
Storage Temperature Range
-65C to +150C
Lead Temperature (Soldering 10 sec)
+300C
Operating Ratings
Thermal Resistance
Package
(
JC
)
(
JA
)
SOIC
50C/W
145C/W
Nominal Operating Voltage
2.5V to
6V
Operating Temperature Range
-40C to +85C
+5V Electrical Characteristics
(Note 2)
A
V
= +2, R
L
= 100
, V
S
= +5V (Note 4), Unless Specified. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Frequency Domain Response
SSBW
-3dB Bandwidth
V
O
=0.5V
PP
70
110
MHz
V
O
=2.0V
PP
90
SSBW
-0.1dB Bandwidth
V
O
=0.5V
PP
23
MHz
GFP
Gain Peaking
<
200MHz, V
O
=0.5V
PP
0
dB
GFR
Gain Rolloff
<
30MHz, V
O
=0.5V
PP
0.2
dB
LPD
Linear Phase Deviation
<
30MHz, V
O
= 0.5V
PP
0.12
deg
Time Domain Response
Tr
Rise and Fall Time
2V Step
4.8
ns
Ts
Settling Time to 0.05%
1V Step
20
ns
OS
Overshoot
2V Step
5
%
SR
Slew Rate
2V Step
250
400
V/s
Distortion And Noise Response
HD2
2nd Harmonic Distortion
2V
PP
, 1MHz
-85
dBc
2V
PP
, 1MHz; R
L
= 1k
-88
2V
PP
, 5MHz
-73
HD3
3rd Harmonic Distortion
2V
PP
,1MHz
-89
dBc
2V
PP
, 1MHz, R
L
= 1k
-91
2V
PP
, 5MHz
-71
XTLKA
Crosstalk (Input Referred)
10MHz, 1V
PP
-85
dB
Static, DC Performance
V
IO
Input Offset Voltage
.6
10
20
mV
DV
IO
Average Drift
10
V/C
I
BN
Input Bias Current
(Non-Inverting)
.6
15
20
A
DI
BN
Average Drift
20
nA/C
GACC
Gain Accuracy
0.3
1.5
2.0
%
Internal Resistors (R
F
, R
G
)
750
950
1150
PSRR
Power supply Rejection Ratio
DC
50
60
dB
CMRR
Common Mode Rejection Ratio
DC
50
47
56
dB
I
CC
Supply Current per channel
R
L
=
2.0
1.9
2.4
3.0
3.1
mA
Miscellaneous Performance
R
IN
Input Resistance (Non-Inverting)
0.38
M
LMH6718
www.national.com
2
+5V Electrical Characteristics
(Note 2) (Continued)
A
V
= +2, R
L
= 100
, V
S
= +5V (Note 4), Unless Specified. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
C
IN
Input Capacitance
(Non-Inverting)
2.2
pF
V
CMH
Input Voltage Range, High
4.2
V
V
CML
Input Voltage Range, Low
0.8
V
V
ROH
Output Voltage Range, High
R
L
= 100
3.6
3.5
4.0
V
V
ROL
Output Voltage Range, Low
R
L
= 100
1.4
1.3
1.0
V
V
ROH
Output Voltage Range, High
R
L
=
4.1
V
V
ROL
Output Voltage Range, Low
R
L
=
0.9
V
I
O
Output Current (Note 3)
170
mA
R
O
Output Resistance, Closed Loop
DC
.28
5V Electrical Characteristics
(Note 2)
A
V
= +2, R
L
= 100
, V
CC
=
5V; Unless Specified. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Frequency Domain Response
SSBW
-3dB Bandwidth
V
O
=1.0V
PP
100
130
MHz
V
O
=4.0V
PP
70
SSBW
-0.1dB Bandwidth
V
O
= 1.0V
PP
30
MHz
GFP
Gain Peaking
<
200MHz, V
O
= 1.0V
PP
0
dB
GFR
Gain Rolloff
<
300MHz, V
O
= 1.0V
PP
0.1
dB
LPD
Linear Phase Deviation
<
30MHz, V
O
= 1.0V
PP
0.1
deg
DG
Differential Gain
NTSC, R
L
= 150
.04
%
DP
Differential Phase
NTSC, R
L
= 150
.03
deg
Time Domain Response
Tr
Rise and Fall Time
2V Step
4.2
ns
Ts
Settling Time to 0.05%
2V Step
17
ns
OS
Overshoot
2V Step
14
%
SR
Slew Rate
2V Step
400
600
V/s
Distortion And Noise Response
HD2
2nd Harmonic Distortion
2V
PP
,1MHz
-84
dBc
2V
PP
, 1MHz; R
L
=1k
-88
2V
PP
, 5MHz
-73
HD3
3rd Harmonic Distortion
2V
PP
,1MHz
-84
dBc
2V
PP
, 1MHz; R
L
= 1k
-98
2V
PP
, 5MHz
-76
Equivalent Input Noise
V
N
Voltage (e
ni
)
>
1MHz
8
nV/
I
NN
Non-Inverting Current (i
bn
)
>
1MHz
9
pA/
XTLKA
Crosstalk (Input Referred)
10MHz, 1V
PP
-85
dB
Static, DC Performance
V
IO
Input Offset Voltage
.2
9.5
15
mV
DV
IO
Average Drift
5
V/C
I
BN
Input Bias Current
(Non-Inverting)
1.3
15
20
A
DI
BN
Average Drift
12
nA/C
LMH6718
www.national.com
3
5V Electrical Characteristics
(Note 2) (Continued)
A
V
= +2, R
L
= 100
, V
CC
=
5V; Unless Specified. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
Typ
Max
Units
GACC
Gain Accuracy
0.3
1.5
2.0
%
Internal Resistor (R
F
, R
G
)
750
950
1150
PSRR
Power Supply Rejection Ratio
DC
50
62
dB
CMRR
Common Mode Rejection Ratio
DC
52
49
57
dB
I
CC
Supply Current per channel
R
L
=
2.2
2.1
2.6
3.3
3.4
mA
Miscellaneous Performance
R
IN
Input Resistance (Non-Inverting)
0.50
M
C
IN
Input Capacitance
(Non-Inverting)
1.9
pF
CMVR
Common-Mode Voltage Range
4.2
V
V
RO
Output Voltage Range
R
L
= 100
3.6
3.5
3.8
V
V
RO
Output Voltage Range
R
L
=
4.0
V
I
O
Output Current (Note 3)
200
mA
R
O
Output Resistance, Closed Loop
DC
.28
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.
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
J
= T
A
. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self heating where T
J
>
T
A
.
See Applications Section 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.
Note 3: The maximum current is determined by device power dissipation limitations. See the Power Dissipation section of the Application Division for more details.
Note 4: V
S
= V
CC
- V
EE
Note 5: Human body model, 1.5k
in series with 100pF. Machine model, 0 In series with 200pF.
Ordering Information
Package
Part Number
Package Marking
Transport Media
NSC Drawing
8-pin SOIC
LMH6718MA
LMH6718MA
Rails
M08A
LMH6718IMAX
2.5k Units Tape and Reel
LMH6718
www.national.com
4
Typical Performance Characteristics
(A
V
= +2, R
L
= 100
, Unless Specified).
Frequency Response vs. Gain
Frequency Response
20040106
20040123
Frequency Response R
L
Frequency Response vs. R
L
20040125
20040124
Gain Flatness & Linear Phase
Gain Flatness & Linear Phase
20040107
20040122
LMH6718
www.national.com
5
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