LMH6645/46/47
2.7V, 650A, 55MHz, Rail-to-Rail Input and Output
Amplifiers with Shutdown Option
General Description
The LMH6645 (single) and LMH6646 (dual), rail-to-rail input
and output voltage feedback amplifiers, offer high speed
(55MHz), and low voltage operation (2.7V) in addition to
micro-power shutdown capability (LMH6647, single).
Input common mode voltage range exceeds either supply by
0.3V, enhancing ease of use in multitude of applications
where previously only inferior devices could be used. Output
voltage range extends to within 20mV of either supply rails,
allowing wide dynamic range especially in low voltage appli-
cations. Even with low supply current of 650A/amplifier,
output current capability is kept at a respectable
20mA for
driving heavier loads. Important device parameters such as
BW, Slew Rate and output current are kept relatively inde-
pendent of the operating supply voltage by a combination of
process enhancements and design architecture.
In portable applications, the LMH6647 provides shutdown
capability while keeping the turn-off current to less than
50A. Both turn-on and turn-off characteristics are well be-
haved with minimal output fluctuations during transitions.
This allows the part to be used in power saving mode, as
well as multiplexing applications. Miniature packages
(SOT23, MSOP-8, and SO-8) are further means to ease the
adoption of these low power high speed devices in applica-
tions where board area is at a premium.
Features
(V
S
= 2.7V, T
A
= 25C, R
L
= 1k
to V
+
/2, A
V
= +1. Typical
values unless specified).
n
-3dB BW
55MHz
n
Supply voltage range
2.5V to 12V
n
Slew rate
22V/s
n
Supply current
650A/channel
n
Output short circuit current
42mA
n
Linear output current
20mA
n
Input common mode voltage
0.3V beyond rails
n
Output voltage swing
20mV from rails
n
Input voltage noise
17nV/
n
Input current noise
0.75pA/
Applications
n
Active filters
n
High speed portable devices
n
Multiplexing applications (LMH6647)
n
Current sense buffer
n
High speed transducer amp
Connection Diagrams
SOT23-5 (LMH6645)
SOT23-6 (LMH6647)
SOIC-8 (LMH6645)
20020259
Top View
20020260
Top View
20020261
Top View
February 2002
LMH6645/46/47
2.7V
,
650A,
55MHz,
Rail-to-Rail
Input
and
Output
Amplifiers
with
Shutdown
Option
2002 National Semiconductor Corporation
DS200202
www.national.com
Connection Diagrams
(Continued)
SOIC-8 (LMH6647)
SOIC-8 and MSOP-8
(LMH6646)
20020262
Top View
20020263
Top View
Ordering Information
Package
Part Number
Package Marking
Transport Media
NSC Drawing
5-Pin SOT-23
LMH6645MF
A68A
1k Units Tape and Reel
MF05A
LMH6645MFX
3k Units Tape and Reel
6-Pin SOT-23
LMH6647MF
A69A
1k Units Tape and Reel
MF06A
LMH6647MFX
3k Units Tape and Reel
SOIC-8
LMH6645MA
LMH6645MA
95 Units Rails
M08A
LMH6645MAX
2.5k Units Tape and Reel
LMH6646MA
LMH6646MA
95 Units Rails
LMH6646MAX
2.5k Units Tape and Reel
LMH6647MA
LMH6647MA
95 Units Rails
LMH6647MAX
2.5k Units Tape and Reel
MSOP-8
LMH6646MM
A70A
1k Units Tape and Reel
MUA08A
LMH6646MMX
3.5k Units Tape and Reel
LMH6645/46/47
www.national.com
2
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
Human Body
2KV (Note 2)
Machine Model
200V (Note 9)
V
IN
Differential
2.5V
Output Short Circuit Duration
(Note 3, 11)
Supply Voltage (V
+
- V
-
)
12.6V
Voltage at Input/Output pins
V
+
+0.8V, V
-
-0.8V
Storage Temperature Range
-65C to +150C
Junction Temperature (Note 4)
+150C
Soldering Information
Infrared or Convection (20 sec)
235C
Wave Soldering (10 sec)
260C
Operating Ratings
(Note 1)
Supply Voltage (V
+
V
-
)
2.5V to 12V
Junction Temperature Range (Note 4)
-40C to +85C
Package Thermal Resistance (Note 4) (
JA
)
SOT23-5
265C/W
SOT23-6
265C/W
SOIC-8
190C/W
MSOP-8
235C/W
2.7V Electrical Characteristics
Unless otherwise specified, all limits guaranteed for at T
J
= 25C, V
+
= 2.7V, V
-
= 0V, V
CM
= V
O
= V
+
/2, and R
f
= 2k
, and R
L
= 1k
to V
+
/2. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Units
BW
-3dB BW
A
V
= +1, V
OUT
= 200mV
PP
,
V
CM
= 0.7V
40
55
MHz
e
n
Input-Referred Voltage Noise
f = 100kHz
17
nV/
f = 1kHz
25
i
n
Input-Referred Current Noise
f = 100kHz
0.75
pA/
f = 1kHz
1.20
CT Rej.
Cross-Talk Rejection
(LMH6646 only)
f = 5MHz, Receiver:
R
f
= R
g
= 510
, A
V
= +2
47
dB
SR
Slew Rate
A
V
= -1, V
O
= 2V
PP
(Note 8, 13)
15
22
V/s
T
ON
Turn-On Time
(LMH6647 only)
250
ns
T
OFF
Turn-Off Time
(LMH6647 only)
560
ns
TH
SD
Shutdown Threshold
(LMH6647 only)
I
S
50A
1.95
2.30
V
I
SD
Shutdown Pin Input Current
(LMH6647 only)
(Note 7)
-20
A
V
OS
Input Offset Voltage
0V
V
CM
2.7V
-3
-4
1
3
4
mV
TC V
OS
Input Offset Average Drift
(Note 12)
5
V/C
I
B
Input Bias Current
V
CM
= 2.5V (Note 7)
0.40
2
2.2
A
V
CM
= 0.5V (Note 7)
-0.68
-2
-2.2
I
OS
Input Offset Current
0V
V
CM
2.7V
1
500
nA
R
IN
Common Mode Input
Resistance
3
M
C
IN
Common Mode Input
Capacitance
2
pF
CMVR
Input Common-Mode Voltage
Range
CMRR
50dB
-0.5
-0.3
-0.1
V
3.0
2.8
3.2
LMH6645/46/47
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3
2.7V Electrical Characteristics
(Continued)
Unless otherwise specified, all limits guaranteed for at T
J
= 25C, V
+
= 2.7V, V
-
= 0V, V
CM
= V
O
= V
+
/2, and R
f
= 2k
, and R
L
= 1k
to V
+
/2. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Units
CMRR
Common Mode Rejection
Ratio
V
CM
Stepped from 0V to 2.7V
46
77
dB
V
CM
Stepped from 0V to 1.55V
58
76
A
VOL
Large Signal Voltage Gain
V
O
= 0.35V to 2.35V
76
74
87
dB
V
O
Output Swing
High
R
L
= 1k to V
+
/2
2.55
2.66
V
R
L
= 10k to V
+
/2
2.68
Output Swing
Low
R
L
= 1k to V
+
/2
40
150
mV
R
L
= 10k to V
+
/2
20
I
SC
Output Short Circuit Current
Sourcing to V
-
V
ID
= 200mV (Note 10)
43
mA
Sinking to V
+
V
ID
= -200mV (Note 10)
42
I
OUT
Output Current
V
OUT
= 0.5V from rails
20
mA
PSRR
Power Supply Rejection Ratio
V
+
= 2.7V to 3.7V or
V
-
= 0V to -1V
75
83
dB
I
S
Supply Current (per channel)
Normal Operation
650
1250
A
Shutdown Mode (LMH6647 only)
15
50
5V Electrical Characteristics
Unless otherwise specified, all limits guaranteed for at T
J
= 25C, V
+
= 5V, V
-
= 0V, V
CM
= V
O
= V
+
/2, and R
f
= 2k
, and R
L
= 1k
to V
+
/2. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Units
BW
-3dB BW
A
V
= +1, V
OUT
= 200mV
PP
40
55
MHz
e
n
Input-Referred Voltage Noise
f = 100kHz
17
nV/
f = 1kHz
25
i
n
Input-Referred Current Noise
f = 100kHz
0.75
pA/
f = 1kHz
1.20
CT Rej.
Cross-Talk Rejection
(LMH6646 only)
f = 5MHz, Receiver:
R
f
= R
g
= 510
, A
V
= +2
47
dB
SR
Slew Rate
A
V
= -1, V
O
= 2V
PP
(Note 8, 13)
15
22
V/s
T
ON
Turn-On Time (LMH6647 only)
210
ns
T
OFF
Turn-Off Time (LMH6647 only)
500
ns
TH
SD
Shutdown Threshold
(LMH6647 only)
I
S
50A
4.25
4.60
V
I
SD
Shutdown Pin Input Current
(LMH6647 only)
(Note 7)
-20
A
V
OS
Input Offset Voltage
0V
V
CM
5V
-3
-4
1
3
4
mV
TC V
OS
Input Offset Average Drift
(Note 12)
5
V/C
I
B
Input Bias Current
V
CM
= 4.8V (Note 7)
+0.36
+2
-2.2
A
V
CM
= 0.5V (Note 7)
-0.68
-2
-2.2
I
OS
Input Offset Current
0V
V
CM
5V
1
500
nA
R
IN
Common Mode Input
Resistance
3
M
LMH6645/46/47
www.national.com
4
5V Electrical Characteristics
(Continued)
Unless otherwise specified, all limits guaranteed for at T
J
= 25C, V
+
= 5V, V
-
= 0V, V
CM
= V
O
= V
+
/2, and R
f
= 2k
, and R
L
= 1k
to V
+
/2. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Units
C
IN
Common Mode Input
Capacitance
2
pF
CMVR
Input Common-Mode Voltage
Range
CMRR
50dB
-0.5
-0.3
-0.1
V
5.3
5.1
5.5
CMRR
Common Mode Rejection
Ratio
V
CM
Stepped from 0V to 5V
56
82
dB
V
CM
Stepped from 0V to 3.8V
66
85
A
VOL
Large Signal Voltage Gain
V
O
= 1.5V to 3.5V
76
74
85
dB
V
O
Output Swing
High
R
L
= 1k to V
+
/2
4.80
4.95
V
R
L
= 10k to V
+
/2
4.98
Output Swing
Low
R
L
= 1k to V
+
/2
50
200
mV
R
L
= 10k to V
+
/2
20
I
SC
Output Short Circuit Current
Sourcing to V
-
V
ID
= 200mV (Note 10)
55
mA
Sinking to V
+
V
ID
= -200mV (Note 10)
53
I
OUT
Output Current
V
OUT
= 0.5V From rails
20
mA
PSRR
Power Supply Rejection Ratio
V
+
= 5V to 6V or V
-
= 0V to -1V
75
95
dB
I
S
Supply Current (per channel)
Normal Operation
700
1400
A
Shutdown Mode (LMH6647 only)
10
50
5V Electrical Characteristics
Unless otherwise specified, all limits guaranteed for at T
J
= 25C, V
+
= 5V, V
-
= -5V, V
CM
= V
O
= 0V, R
f
= 2k
, and R
L
=
1k
to GND. Boldface limits apply at the temperature extremes.
Symbol
Parameter
Conditions
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Units
BW
-3dB BW
A
V
= +1, V
OUT
= 200mV
PP
40
55
MHz
e
n
Input-Referred Voltage Noise
f = 100kHz
17
nV/
f = 1kHz
25
i
n
Input-Referred Current Noise
f = 100kHz
0.75
pA/
f = 1kHz
1.20
CT Rej.
Cross-Talk Rejection
(LMH6646 only)
f = 5MHz, Receiver:
R
f
= R
g
= 510
, A
V
= +2
47
dB
SR
Slew Rate
A
V
= -1, V
O
= 2V
PP
(Note 8)
15
22
V/s
T
ON
Turn-On Time (LMH6647 only)
200
ns
T
OFF
Turn-Off Time (LMH6647 only)
700
ns
TH
SD
Shutdown Threshold
(LMH6647 only)
I
S
50A
4.25
4.60
V
I
SD
Shutdown Pin Input Current
(LMH6647 only)
(Note 7)
-20
A
V
OS
Input Offset Voltage
-5V
V
CM
5V
-3
-4
1
3
4
mV
TC V
OS
Input Offset Average Drift
(Note 12)
5
V/C
LMH6645/46/47
www.national.com
5
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