1
OPA687
OPA687
1998 Burr-Brown Corporation
PDS-1372C
Printed in U.S.A. May, 2000
Wideband, Ultra-Low Noise,
Voltage Feedback OPERATIONAL AMPLIFIER
With Power Down
FEATURES
q
HIGH GAIN BANDWIDTH: 3.8GHz
q
LOW INPUT VOLTAGE NOISE: 0.95nV/
Hz
q
VERY LOW DISTORTION: 95dBc (5MHz)
q
LOW DISABLED POWER: 2mW
q
VERY HIGH SLEW RATE: 900V/
s
q
STABLE FOR G
12
DESCRIPTION
The OPA687 combines a very high gain bandwidth and
large signal performance with an ultra-low input noise
voltage (0.95nV/
Hz) while dissipating only 18mA sup-
ply current. Where power savings is paramount, the
OPA687 also includes an optional power down pin that,
when pulled low, will disable the amplifier and decrease
the quiescent current to only 1% of its powered up value.
This optional feature may be left disconnected to insure
normal amplifier operation when no power-down is re-
quired.
The combination of low input voltage and current noise,
along with a 3.8GHz gain bandwidth product, make the
OPA687 an ideal amplifier for wideband transimpedance
APPLICATIONS
q
LOW DISTORTION ADC DRIVER
q
OC-3 FIBER OPTIC RECEIVER
q
LOW NOISE DIFFERENTIAL AMPLIFIERS
q
EQUALIZING RECEIVERS
q
ULTRASOUND CHANNEL AMPLIFIERS
q
IMPROVED REPLACEMENT FOR THE
CLC425
TM
stages. As a voltage gain stage, the OPA687 is opti-
mized for a flat frequency response at a gain of +20 and
is guaranteed stable down to gains of +12. New external
compensation techniques allows the OPA687 to be used
at any inverting gain with excellent frequency response
control. Using this compensation can give an extremely
high dynamic range ADC driver to support > 40MSPS
12- and 14-bit converters.
Ultra-High Dynamic Range
Differential Input ADC Driver
+5V
5V
OPA687
+5V
+5V
5V
850
39pF
OPA687
1.7pF
80pF
V
IN
+
V
IN
80pF
1.7pF
850
39pF
100
20
20
1:2
50
Source
< 6dB
Noise
Figure
ADS852
14-Bit
65MSPS
100
V
CM
V
CM
OPA687
IInternational Airport Industrial Park Mailing Address: PO Box 11400, Tucson, AZ 85734 Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 Tel: (520) 746-1111
Twx: 910-952-1111 Internet: http://www.burr-brown.com/ Cable: BBRCORP Telex: 066-6491 FAX: (520) 889-1510 Immediate Product In
Center Frequency (MHz)
3rd-Order Spurious (dBc)
0
60
65
70
75
80
85
5
10
15
20
25
30
35
40
45
50
4Vp-p
2Vp-p
Measured 2-Tone, 3rd-Order Distortion for
Differential ADC Driver.
OPA687 RELATED PRODUCTS
INPUT NOISE
GAIN BANDWIDTH
SINGLES
DUAL
VOLTAGE (nV/
Hz)
PRODUCT (MHz)
OPA642
2.7
210
OPA643
2.3
800
OPA686
OPA2686
1.3
1600
For most current data sheet and other product
information, visit www.burr-brown.com
2
OPA687
OPA687U, N
TYP
GUARANTEED
0
C to
40
C to
MIN/
TEST
PARAMETER
CONDITIONS
+25
C
+25
C
(2)
70
C
(3)
+85
C
(3)
UNITS
MAX LEVEL
(1)
SPECIFICATIONS: V
S
=
5V
R
L
= 100
, R
F
= 750
,
and R
G
= 39.2
, G = +20 (Figure 1 for AC performance only), unless otherwise noted.
NOTES: (1) Test Levels: (A) 100% tested at 25
C. Over temperature limits by characterization and simulation. (B) Limits set by characterization and simulation.
(C) Typical value only for information. (2) Junction temperature = ambient for +25
C guaranteed specifications. (3) Junction temperature = ambient at low temperature
limit: junction temperature = ambient +23
C at high temperature limit for over temperature guaranteed specifications. (4) Current is considered positive out of node. V
CM
is the input common-mode voltage. (5) Tested <3dB below minimum specified CMRR at
CMIR limits.
AC PERFORMANCE (Figure 1)
Closed-Loop Bandwidth
G = +12, R
G
= 39.2
, V
O
= 200mVp-p
600
MHz
typ
C
G = +20, R
G
= 39.2
, V
O
= 200mVp-p
290
180
160
140
MHz
min
B
G = +50, R
G
= 39.2
, V
O
= 200mVp-p
75
60
54
48
MHz
min
B
Gain Bandwidth Product
G
+50
3800
3000
2700
2400
MHz
min
B
Bandwidth for 0.1dB Gain Flatness
G = +20, R
L
= 100
35
24
20
18
MHz
min
B
Peaking at a Gain of +12
3
8
10
14
dB
max
B
Harmonic Distortion
G = +20, f = 5MHz, V
O
= 2Vp-p
2nd Harmonic
R
L
= 100
74
70
68
65
dBc
max
B
R
L
= 500
95
90
88
85
dBc
max
B
3rd Harmonic
R
L
= 100
108
95
90
85
dBc
max
B
R
L
= 500
110
105
100
95
dBc
max
B
Two-Tone, 3rd-Order Intercept
G = +20, f = 20MHz
43
40
39
37
dBm
min
B
Input Voltage Noise Density
f > 1MHz
0.95
1.1
1.15
1.3
nV/
Hz
max
B
Input Current Noise Density
f > 1MHz
2.5
3.2
3.3
3.5
pA/
Hz
max
B
Pulse Response
Rise/Fall Time
0.2V Step
1.2
2.0
2.2
2.5
ns
max
B
Slew Rate
2V Step
900
675
550
450
V/
s
min
B
Settling Time to 0.01%
2V Step
17
ns
typ
C
0.1%
2V Step
15
18
20
25
ns
max
B
1%
2V Step
8
11
13
17
ns
max
B
DC PERFORMANCE
(4)
Open-Loop Voltage Gain (A
OL
)
V
O
= 0V
85
78
75
70
dB
min
A
Input Offset Voltage
V
CM
= 0V
0.1
1
1.2
1.6
mV
max
A
Average Offset Voltage Drift
V
CM
= 0V
5
10
V/
C
max
B
Input Bias Current
V
CM
= 0V
20
33
36
40
A
max
A
Input Bias Current Drift (magnitude)
V
CM
= 0V
50
100
nA/
C
max
B
Input Offset Current
V
CM
= 0V
0.2
1.0
1.5
1.8
A
max
A
Input Offset Current Drift
V
CM
= 0V
12
15
nA/
C
max
B
INPUT
Common-Mode Input Range (CMIR)
(5)
3.2
3.0
2.9
2.8
V
min
A
Common-Mode Rejection Ratio (CMRR)
V
CM
=
0.5V, Input Referred
100
88
83
78
dB
min
A
Input Impedance
Differential
V
CM
= 0V
2.5 || 2.5
k
|| pF
typ
C
Common-Mode
V
CM
= 0V
1.0 || 1.2
M
|| pF
typ
C
OUTPUT
Output Voltage Swing
400
Load
3.6
3.3
3.1
3.0
V
min
A
100
Load
3.5
3.2
2.9
2.8
V
min
A
Current Output, Sourcing
V
O
= 0V
80
60
50
40
mA
min
A
Current Output, Sinking
V
O
= 0V
80
60
50
40
mA
min
A
Closed-Loop Output Impedance
G = +20, f = < 100kHz
0.006
typ
C
POWER SUPPLY
Specified Operating Voltage
5
V
typ
C
Maximum Operating Voltage
6
6
6
6
V
max
A
Quiescent Current, max
V
S
=
5V
18.5
19
19.5
20.5
mA
max
A
Quiescent Current, min
V
S
=
5V
18.5
18
17.5
16
mA
min
A
Power Supply Rejection Ratio
+PSRR, PSRR
|V
S
| = 4.5V to 5.5V, Input Referred
85
80
78
75
dB
min
A
POWER-DOWN (Disabled Low)
(Pin 8 SO-8; Pin 5 on SOT23-6)
Power-Down Quiescent Current (+V
S
)
225
300
350
400
A
max
A
On Voltage (Enabled High or Floated)
3.3
3.5
3.6
3.7
V
min
A
Off Voltage (Disabled Asserted Low)
1.8
1.7
1.6
1.5
V
max
A
Power-Down Pin Input Bias Current
(V
DIS
= 0)
100
160
160
160
A
max
A
Power-Down Time
200
ns
typ
C
Power-Up Time
60
ns
typ
C
Off Isolation
5MHz, Input to Output
70
dB
typ
C
THERMAL
Specification U, N
40 to +85
C
typ
C
Thermal Resistance,
JA
Junction to Ambient
U 8-Pin, SO-8
125
C/W
typ
C
N 6-Pin, SOT23
150
C/W
typ
C
3
OPA687
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility for the use of this
information, and all use of such information shall be entirely at the user's own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described
herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems.
PACKAGE
SPECIFIED
DRAWING
TEMPERATURE
PACKAGE
ORDERING
TRANSPORT
PRODUCT
PACKAGE
NUMBER
(1)
RANGE
MARKING
NUMBER
(2)
MEDIA
OPA687U
SO-8 Surface-Mount
182
40
C to +85
C
OPA687U
OPA687U
Rails
"
"
"
"
"
OPA687U/2K5
Tape and Reel
OPA687N
6-Lead SOT23-6
332
40
C to +85
C
A87
OPA687N/250
Tape and Reel
"
"
"
"
"
OPA687N/3K
Tape and Reel
NOTES: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book. (2) Models with a slash (/ ) are
available only in Tape and Reel in the quantities indicated (e.g., /2K5 indicates 2500 devices per reel). Ordering 2500 pieces of "OPA687U/2K5" will get a single
2500-piece Tape and Reel. For detailed Tape and Reel mechanical information, refer to Appendix B of Burr-Brown IC Data Book.
PACKAGE/ORDERING INFORMATION
ELECTROSTATIC
DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Burr-Brown
recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.
ESD damage can range from subtle performance degrada-
tion to complete device failure. Precision integrated circuits
may be more susceptible to damage because very small
parametric changes could cause the device not to meet its
published specifications.
ABSOLUTE MAXIMUM RATINGS
Power Supply ................................................................................
6.5V
DC
Internal Power Dissipation ...................................... See Thermal Analysis
Differential Input Voltage ..................................................................
1.2V
Input Voltage Range ............................................................................
V
S
Storage Temperature Range: U, N ................................. 40
C to +125
C
Lead Temperature (soldering, 10s) ............................................... +300
C
Junction Temperature (T
J
) ............................................................. +175
C
PIN CONFIGURATION
Top View
SO-8
Top View
SOT23-6
1
2
3
6
5
4
Output
V
S
Noninverting Input
+V
S
DIS
Inverting Input
OPA687
1
2
3
6
5
4
A87
Pin Orientation/Package Marking
8
7
6
5
1
2
3
4
OPA687
NC: No Connection
NC
Inverting Input
Noninverting Input
V
S
DIS
+V
S
Output
NC
4
OPA687
TYPICAL PERFORMANCE CURVES: V
S
=
5V
R
F
= 750
, R
G
= 39.2
, G = +20 and R
L
= 100
,
unless otherwise noted.
6
3
0
3
6
9
12
15
18
21
24
NONINVERTING SMALL-SIGNAL
FREQUENCY RESPONSE
Frequency (MHz)
Normalized Gain (3dB/div)
1
10
100
1000
R
G
= 39.2
V
O
= 0.2Vp-p
G = +30
G = +50
See Figure 1
G = +12
G = +20
6
3
0
3
6
9
12
15
18
21
24
INVERTING SMALL-SIGNAL
FREQUENCY RESPONSE
Frequency (MHz)
Normalized Gain (3dB/div)
1
10
100
1000
R
G
= R
S
= 50
V
O
= 0.2Vp-p
G = 40
G = 50
See Figure 2
G = 20
G = 30
32
29
26
23
20
17
14
11
8
5
2
NONINVERTING LARGE-SIGNAL
FREQUENCY RESPONSE
Frequency (MHz)
Gain (3dB/div)
1
10
100
1000
R
G
= 39.2
G = +20V/V
V
O
= 2Vp-p
V
O
= 0.2Vp-p
V
O
= 5Vp-p
See Figure 1
V
O
= 1Vp-p
200
100
0
100
200
1.2
0.8
0.4
0
0.4
0.8
1.2
NONINVERTING PULSE RESPONSE
Time (5ns/div)
Output Voltage (100mV/div)
Output Voltage (400mV/div)
G = +20V/V
See Figure 1
Large Signal
1V
Small Signal
100mV
Right Scale
Left Scale
38
35
32
29
26
23
20
18
14
13
10
INVERTING LARGE-SIGNAL
FREQUENCY RESPONSE
Frequency (MHz)
Gain (3dB/div)
1
10
100
1000
R
G
= R
S
= 50
G = 40V/V
V
O
= 2Vp-p
V
O
= 0.2Vp-p
See Figure 2
V
O
= 1Vp-p
V
O
= 5Vp-p
200
100
0
100
200
1.2
0.8
0.4
0
0.4
0.8
1.2
INVERTING PULSE RESPONSE
Time (5ns/div)
Output Voltage (100mV/div)
Output Voltage (400mV/div)
G = 40V/V
See Figure 2
Large Signal
1V
Small Signal
100mV
Right Scale
Left Scale
5
OPA687
TYPICAL PERFORMANCE CURVES: V
S
=
5V
(CONT)
R
F
= 750
, R
G
= 39.2
, G = +20 and R
L
= 100
,
unless otherwise noted (Figure 1).
70
80
90
100
110
Output Voltage (Vp-p)
0.1
10
1
5MHz 2nd HARMONIC DISTORTION
vs OUTPUT VOLTAGE
2nd Harmonic Distortion (dBc)
R
L
= 200
R
L
= 100
R
L
= 500
70
80
90
100
110
Output Voltage (Vp-p)
0.1
10
1
5MHz 3rd HARMONIC DISTORTION
vs OUTPUT VOLTAGE
3rd Harmonic Distortion (dBc)
R
L
= 100
R
L
= 500
R
L
=200
60
70
80
90
100
Output Voltage (Vp-p)
0.1
10
1
10MHz 2nd HARMONIC DISTORTION
vs OUTPUT VOLTAGE
2nd Harmonic Distortion (dBc)
R
L
= 200
R
L
= 100
R
L
= 500
60
70
80
90
100
Output Voltage (Vp-p)
0.1
10
1
10MHz 3rd HARMONIC DISTORTION
vs OUTPUT VOLTAGE
3rd Harmonic Distortion (dBc)
R
L
= 200
R
L
= 100
R
L
= 500
50
60
70
80
90
Output Voltage (Vp-p)
0.1
10
1
20MHz 2nd HARMONIC DISTORTION
vs OUTPUT VOLTAGE
2nd Harmonic Distortion (dBc)
R
L
= 200
R
L
= 100
R
L
= 500
50
60
70
80
90
Output Voltage (Vp-p)
0.1
10
1
20MHz 3rd HARMONIC DISTORTION
vs OUTPUT VOLTAGE
3rd Harmonic Distortion (dBc)
R
L
= 200
R
L
= 100
R
L
= 500
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