TI1 OPA690IDBVR Wideband, voltage-feedback operational amplifier with disable Datasheet

OPA690
www.ti.com
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
Wideband, Voltage-Feedback
OPERATIONAL AMPLIFIER with Disable
Check for Samples: OPA690
FEATURES
DESCRIPTION
•
The OPA690 represents a major step forward in
unity-gain stable, voltage-feedback op amps. A new
internal architecture provides slew rate and full-power
bandwidth previously found only in wideband,
current-feedback op amps. A new output stage
architecture delivers high currents with a minimal
headroom requirement. These combine to give
exceptional single-supply operation. Using a single
+5V supply, the OPA690 can deliver a 1V to 4V
output swing with over 150mA drive current and
150MHz bandwidth. This combination of features
makes the OPA690 an ideal RGB line driver or
single-supply Analog-to-Digital Converter (ADC) input
driver.
1
2
•
•
•
•
•
•
•
FLEXIBLE SUPPLY RANGE:
+5V to +12V Single Supply
±2.5V to ±5V Dual Supply
UNITY-GAIN STABLE: 500MHz (G = 1)
HIGH OUTPUT CURRENT: 190mA
OUTPUT VOLTAGE SWING: ±4.0V
HIGH SLEW RATE: 1800V/µs
LOW SUPPLY CURRENT: 5.5mA
LOW DISABLE CURRENT: 100µA
WIDEBAND +5V OPERATION: 220MHz (G = 2)
APPLICATIONS
•
•
•
•
•
•
•
VIDEO LINE DRIVING
xDSL LINE DRIVER/RECEIVER
HIGH-SPEED IMAGING CHANNELS
ADC BUFFERS
PORTABLE INSTRUMENTS
TRANSIMPEDANCE AMPLIFIERS
ACTIVE FILTERS
The low 5.5mA supply current of the OPA690 is
precisely trimmed at +25°C. This trim, along with low
temperature drift, gives lower maximum supply
current than competing products. System power may
be reduced further using the optional disable control
pin. Leaving this disable pin open, or holding it HIGH,
will operate the OPA690 normally. If pulled LOW, the
OPA690 supply current drops to less than 100mA
while the output goes to a high-impedance state. This
feature may be used for power savings.
OPA690 RELATED PRODUCTS
SINGLES
DUALS
TRIPLES
Voltage-Feedback
—
OPA2690
OPA3690
Current-Feedback
OPA691
OPA2691
OPA3691
Fixed Gain
OPA692
—
OPA3692
Single-Supply ADC Driver
+5V
R1
R1
3.3V
2.5V
0.1mF
C1
R2
VI
3
8
C2
R4
20W
OPA690
2
4
R3
R5
20W
C4
10mF
THS1040
C3
20pF
C6
20pF
AIN+
10-Bit
40MSPS
AIN-
VREF = 1V
C5
0.1mF
1
2
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2001–2010, Texas Instruments Incorporated
OPA690
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
www.ti.com
This integrated circuit can be damaged by ESD. Texas Instruments 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 degradation 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.
ORDERING INFORMATION (1)
SPECIFIED
TEMPERATURE
RANGE
PACKAGE
MARKING
PRODUCT
PACKAGE-LEAD
PACKAGE
DESIGNATOR
OPA690
SO-8
D
-40°C to +85°C
OPA690
OPA690
SOT23-6
DBV
-40°C to +85°C
OAEI
(1)
ORDERING
NUMBER
TRANSPORT
MEDIA, QUANTITY
OPA690ID
Rails, 100
OPA690IDR
Tape and Reel, 2500
OPA690IDBVT
Tape and Reel, 250
OPA690IDBVR
Tape and Reel, 3000
For the most current package and ordering information, see the Package Option Addendum located at the end of this data sheet, or see
the TI web site at www.ti.com.
ABSOLUTE MAXIMUM RATINGS (1)
Over operating free-air temperature range, unless otherwise noted.
Power Supply
Internal Power Dissipation
OPA690
UNIT
±6.5
VDC
See Thermal Analysis section
Differential Input Voltage
±1.2
Input Voltage Range
±VS
V
–65 to +125
°C
Storage Temperature Range: D, DBV
Junction Temperature (TJ)
ESD Ratings
(1)
V
+175
°C
Human Body Model (HBM)
2000
V
Charge Device Model (CDM)
1500
V
Machine Model (MM)
200
V
Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may
degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond
those specified is not supported.
D PACKAGE
SO-8
(TOP VIEW)
DRB PACKAGE
SOT23-6
(TOP VIEW)
NC
1
8
DIS
Inverting Input
2
7
+VS
Noninverting Input
3
6
Output
-VS
4
5
NC
Output
1
6
+VS
-VS
2
5
DIS
Noninverting Input
3
4
Inverting Input
4
5
6
NOTE: NC = not connected.
3
2
1
OAEI
Pin Orientation/Package Marking
2
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
OPA690
www.ti.com
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
ELECTRICAL CHARACTERISTICS: VS = ±5V
Boldface limits are tested at +25°C.
At RF = 402Ω, RL = 100Ω, and G = +2 (see Figure 36 for ac performance only), unless otherwise noted.
OPA690ID, IDBV
MIN/MAX OVER
TEMPERATURE
TYP
PARAMETER
+25°C (2)
0°C to
+70°C (3)
-40°C to
+85°C (3)
220
165
160
150
G = +10, VO = 0.5VPP
30
20
19
G ≥ 10
300
200
190
G = +2, VO < 0.5VPP
30
TEST CONDITIONS
+25°C
G = +1, VO = 0.5VPP, RF = 25Ω
500
G = +2, VO = 0.5VPP
MIN/
MAX
TEST
LEVELS (1)
MHz
typ
C
MHz
min
B
18
MHz
min
B
180
MHz
min
B
MHz
typ
C
UNIT
AC PERFORMANCE (see Figure 36)
Small-Signal Bandwidth
Gain Bandwidth Product
Bandwidth for 0.1dB Gain Flatness
Peaking at a Gain of +1
VO < 0.5VPP
4
dB
typ
C
Large-Signal Bandwidth
G = +2, VO < 0.5VPP
200
MHz
typ
C
G = +2, 4V Step
1800
V/ms
min
B
G = +2, VO = 0.5V Step
1.4
ns
typ
C
Slew Rate
Rise-and-Fall Time
1400
1200
900
G = +2, VO = 5V Step
2.8
ns
typ
C
Settling Time to 0.02%
G = +2, VO = 2V Step
12
ns
typ
C
Settling Time to 0.1%
G = +2, VO = 2V Step
8
ns
typ
C
Harmonic Distortion
G = +2, f = 5MHz, VO = 2VPP
xx x 2nd-Harmonic
RL = 100Ω
–68
–64
–62
–60
dBc
max
B
RL ≥ 500Ω
–77
–70
–68
–66
dBc
max
B
RL = 100Ω
–70
–68
–66
–64
dBc
max
B
RL ≥ 500Ω
–81
–78
–76
–75
dBc
max
B
f > 1MHz
5.5
nV/√Hz
typ
C
xx x 3rd-Harmonic
Input Voltage Noise
Input Current Noise
f > 1MHz
3.1
pA/√Hz
typ
C
Differential Gain
G = +2, NTSC, VO = 1.4VP, RL = 150Ω
0.06
%
typ
C
Differential Phase
G = +2, NTSC, VO = 1.4VP, RL = 150Ω
0.03
deg
typ
C
DC PERFORMANCE (4)
Open-Loop Voltage Gain (AOL)
VO = 0V, RL = 100Ω
69
58
56
54
dB
min
A
Input Offset Voltage
VCM = 0V
±1.0
±4
±4.5
±4.7
mV
max
A
xxx Average Offset Voltage Drift
VCM = 0V
±10
±10
mV/°C
max
B
Input Bias Current
VCM = 0V
±11
±12
mA
max
A
xxx Average Bias Current Drift (magnitude)
VCM = 0V
±20
±40
nA/°C
max
B
Input Offset Current
VCM = 0V
±1.4
±1.6
mA
max
A
xxx Average Offset Current Drift
VCM = 0V
±7
±9
nA/°C
max
B
±3
±0.1
±10
±1.0
INPUT
Common-mode Input Voltage (CMIR) (5)
±3.5
±3.4
±3.3
±3.2
V
min
A
VCM = ±1V
65
60
57
56
dB
min
A
xxx Differential Mode
VCM = 0V
190 || 0.6
kΩ || pF
typ
C
xxx Common-Mode
VCM = 0V
3.2 || 0.9
MΩ || pF
typ
C
Common-Mode Rejection Ratio (CMRR)
Input Impedance
(1)
(2)
(3)
(4)
(5)
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.
Junction temperature = ambient for +25°C specifications.
Junction temperature = ambient at low temperature limits; junction temperature = ambient +10°C at high temperature limit for over
temperature specifications.
Current is considered positive out of node.
Tested < 3dB below minimum specified CMRR at ±CMIR limits.
3
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
OPA690
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
www.ti.com
ELECTRICAL CHARACTERISTICS: VS = ±5V (continued)
Boldface limits are tested at +25°C.
At RF = 402Ω, RL = 100Ω, and G = +2 (see Figure 36 for ac performance only), unless otherwise noted.
OPA690ID, IDBV
MIN/MAX OVER
TEMPERATURE
TYP
PARAMETER
TEST CONDITIONS
+25°C
+25°C (2)
0°C to
+70°C (3)
-40°C to
+85°C (3)
UNIT
MIN/
MAX
TEST
LEVELS (1)
OUTPUT
Voltage Output Swing
No Load
±4.0
±3.8
±3.7
±3.6
V
min
A
RL = 100Ω
±3.9
±3.7
±3.6
±3.3
V
min
A
Current Output, Sourcing
VO = 0V
+190
+160
+140
+100
mA
min
A
Current Output, Sinking
VO = 0V
–190
–160
–140
–100
mA
min
A
Short-Circuit Current Limit
VO = 0V
±250
mA
typ
C
G = +2, f =100kHz
0.04
Ω
typ
C
Power-Down Supply Current (+VS)
VDIS = 0V
–100
µA
max
A
Disable Time
VIN = 1VDC
200
ns
typ
C
Enable Time
VIN = 1VDC
25
ns
typ
C
Off Isolation
G = +2, RL = 150Ω, VIN = 0V
70
dB
typ
C
Output Capacitance in Disable
G = +2, RL = 150Ω, VIN = 0V
4
pF
typ
C
Turn-On Glitch
±50
mV
typ
C
Turn-Off Glitch
±20
mV
typ
C
Enable Voltage
3.3
3.5
3.6
3.7
V
min
A
Disable Voltage
1.8
1.7
1.6
1.5
V
max
A
75
130
150
160
µA
max
A
V
typ
C
±6.0
±6
±6
V
max
A
Closed-Loop Output Impedance
DISABLE (Disabled LOW)
Control Pin Input BIas Current (VDIS)
VDIS = 0V
–200
–240
–260
POWER SUPPLY
Specified Operating Voltage
±5
Maximum Operating Voltage Range
Maximum Quiescent Current
VS = ±5V
5.5
5.8
6.2
6.6
mA
max
A
Minimum Quiescent Current
VS = ±5V
5.5
5.3
4.6
4.3
mA
min
A
Input-Referred
75
68
66
64
dB
min
A
-40 to +85
°C
typ
C
xx x D xxxx x SO-8
125
°C/W
typ
C
xx x DBV xxx SOT23-6
150
°C/W
typ
C
Power-Supply Rejection Ratio (+PSRR)
THERMAL CHARACTERISTICS
Specified Operating Range: D, DBV
Thermal Resistance, qJA
Junction-to-Ambient
4
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
OPA690
www.ti.com
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
ELECTRICAL CHARACTERISTICS: VS = +5V
Boldface limits are tested at +25°C.
At RF = 402Ω, RL = 100Ω, and G = +2 (see Figure 37 for ac performance only), unless otherwise noted.
OPA690ID, IDBV
MIN/MAX OVER
TEMPERATURE
TYP
PARAMETER
+25°C (2)
0°C to
+70°C (3)
-40°C to
+85°C (3)
190
150
145
140
G = +10, VO < 0.5VPP
25
18
17
G ≥ 10
250
180
170
G = +2, VO < 0.5VPP
20
TEST CONDITIONS
+25°C
G = +1, VO = 0.5VPP, RF = ±25Ω
400
G = +2, VO < 0.5VPP
MIN/
MAX
TEST
LEVELS (1)
MHz
typ
C
MHz
min
B
16
MHz
min
B
160
MHz
min
B
MHz
typ
C
UNIT
AC PERFORMANCE (see Figure 37)
Small-Signal Bandwidth
Gain Bandwidth Product
Bandwidth for 0.1dB Gain Flatness
Peaking at a Gain of +1
VO < 0.5VPP
5
dB
typ
C
Large-Signal Bandwidth
G = +2, VO = 2VPP
220
MHz
typ
C
G = +2, 2V Step
1000
V/ms
min
B
G = +2, VO = 0.5V Step
1.6
ns
typ
C
Slew Rate
Rise-and-Fall Time
700
670
550
G = +2, VO = 2V Step
2.0
ns
typ
C
Settling Time to 0.02%
G = +2, VO = 2V Step
12
ns
typ
C
Settling Time to 0.1%
G = +2, VO = 2V Step
8
ns
typ
C
Harmonic Distortion
G = +2, f = 5MHz, VO = 2VPP
xx x 2nd-Harmonic
RL = 100Ω to VS/2
–65
–60
–59
–56
dBc
max
B
RL ≥ 500Ω to VS/2
–75
–70
–68
–66
dBc
max
B
RL = 100Ω to VS/2
–68
–64
–62
–60
dBc
max
B
RL ≥ 500Ω to VS/2
–77
–73
–71
–70
dBc
max
B
f > 1MHz
5.6
nV/√Hz
typ
C
xx x 3rd-Harmonic
Input Voltage Noise
Input Current Noise
f > 1MHz
3.2
pA/√Hz
typ
C
Differential Gain
G = +2, NTSC, VO = 1.4VP, RL = 150Ω to
VS/2
0.06
%
typ
C
Differential Phase
G = +2, NTSC, VO = 1.4VP, RL = 150Ω to
VS/2
0.02
deg
typ
C
DC PERFORMANCE
(4)
Open-Loop Voltage Gain (AOL)
VO = 2.5V, RL = 100Ω to VS/2
63
56
54
52
dB
min
A
Input Offset Voltage
VCM = 2.5V
±1.0
±4
±4.3
±4.7
mV
max
A
xxx Average Offset Voltage Drift
VCM = 2.5V
±10
±10
mV/°C
max
B
Input Bias Current
VCM = 2.5V
±11
±12
mA
max
A
xxx Average Bias Current Drift (magnitude)
VCM = 2.5V
±20
±40
nA/°C
max
B
Input Offset Current
VCM = 2.5V
±1.4
±1.6
mA
max
A
xxx Average Offset Current Drift
VCM = 2.5V
±7
±9
nA/°C
max
B
±3
±0.3
±10
±1
INPUT
Least Positive Input Voltage (5)
1.5
1.6
1.7
1.8
V
min
A
Most Positive Input Voltage (5)
3.5
3.4
3.3
3.2
V
min
A
63
58
56
54
dB
min
A
Common-Mode Rejection Ratio (CMRR)
VCM = 2.5V ± 0.5V
Input Impedance
xxx Differential Mode
VCM = 2.5V
92 || 1.4
kΩ || pF
typ
C
xxx Common-Mode
VCM = 2.5V
2.2 || 1.5
MΩ || pF
typ
C
(1)
(2)
(3)
(4)
(5)
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.
Junction temperature = ambient for +25°C specifications.
Junction temperature = ambient at low temperature limits; junction temperature = ambient +10°C at high temperature limit for over
temperature specifications.
Current is considered positive out of node.
Tested < 3dB below minimum specified CMRR at ±CMIR limits.
5
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
OPA690
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
www.ti.com
ELECTRICAL CHARACTERISTICS: VS = +5V (continued)
Boldface limits are tested at +25°C.
At RF = 402Ω, RL = 100Ω, and G = +2 (see Figure 37 for ac performance only), unless otherwise noted.
OPA690ID, IDBV
MIN/MAX OVER
TEMPERATURE
TYP
PARAMETER
TEST CONDITIONS
+25°C
+25°C (2)
0°C to
+70°C (3)
-40°C to
+85°C (3)
UNIT
MIN/
MAX
TEST
LEVELS (1)
OUTPUT
Most Positive Output Voltage
No Load
4
3.8
3.6
3.5
V
min
A
RL = 100Ω to 2.5V
3.9
3.7
3.5
3.4
V
min
A
No Load
1
1.2
1.4
1.5
V
min
A
RL = 100Ω to 2.5V
1.1
1.3
1.5
1.7
V
max
A
Current Output, Sourcing
+160
+120
+100
+80
mA
max
A
Current Output, Sinking
–160
–120
–100
–80
mA
min
A
Short-Circuit Current
±250
mA
typ
C
G = +2, f =100kHz
0.04
Ω
typ
C
µA
max
A
dB
typ
C
Least Positive Output Voltage
Closed-Loop Output Impedance
DISABLE (Disabled LOW)
Power-Down Supply Current (+VS)
VDIS = 0V
–100
G = +2, 5MHz
65
4
pF
typ
C
Turn-On Glitch
G = +2, RL = 150Ω, VIN = VS/2
±50
mV
typ
C
Turn-Off Glitch
G = +2, RL = 150Ω, VIN = VS/2
±20
mV
typ
C
A
Off Isolation
Output Capacitance in Disable
–200
–240
–260
Enable Voltage
3.3
3.5
3.6
3.7
V
min
Disable Voltage
1.8
1.7
1.6
1.5
V
max
A
75
130
150
160
µA
typ
C
V
typ
C
12
12
12
V
max
B
A
Control Pin Input BIas Current (VDIS)
VDIS = 0V
POWER SUPPLY
Specified Single-Supply Operating Voltage
5
Maximum Single-Supply Operating Voltage
Maximum Quiescent Current
VS = ±5V
4.9
5.44
5.72
6.02
mA
max
Minimum Quiescent Current
VS = ±5V
4.9
4.48
4.0
3.86
mA
min
A
Input-Referred
72
dB
typ
C
–40 to +85
°C
typ
C
xx x D xxxx x SO-8
125
°C/W
typ
C
xx x DBV xxx SOT23-6
150
°C/W
typ
C
Power-Supply Rejection Ratio (+PSRR)
THERMAL CHARACTERISTICS
Specification: D, DBV
Thermal Resistance, qJA
Junction-to-Ambient
6
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
OPA690
www.ti.com
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
TYPICAL CHARACTERISTICS: VS = ±5V
At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω (see Figure 36 for ac performance only), unless otherwise noted.
SMALL−SIGNAL
FREQUENCY RESPONSE
9
6
VO = 0.5VPP
G = +1
RF = 25W
3
6
0
G=5
-3
-6
VO = 2VPP
Gain (3dB/div)
Normalized Gain (dB)
LARGE−SIGNAL
FREQUENCY RESPONSE
G=2
G = 10
3
VO = 1VPP
0
VO = 4VPP
-9
-3
-12
VO = 7VPP
-6
0.5
-15
0.7 1
10
700
100
1
10
Frequency (MHz)
Frequency (MHz)
Figure 1.
Figure 2.
SMALL-SIGNAL
PULSE RESPONSE
LARGE-SIGNAL
PULSE RESPONSE
G = +2
VO = 0.5VPP
300
G = +2
VO = 5VPP
3
200
Output Voltage (V)
Output Voltage (mV)
500
4
400
100
0
-100
-200
2
1
0
-1
-2
-3
-300
-4
-400
Time (5ns/div)
Time (5ns/div)
0.200
Figure 3.
Figure 4.
COMPOSITE VIDEO
dG/dP
DISABLE FEEDTHROUGH
vs FREQUENCY
+5V
-50
402W
Optional
1.3kW
Pull- Down
dG
402W
0.125
dG
0.100
VDIS = 0
-55
OPA690
0.150
Feedthrough (dB)
75W
-45
No Pull- Down
With 1.3kW Pull- Down
Video In
0.175
dG/dP (%/degree)
100
-5V
dP
0.075
0.050
dP
-60
-65
-70
-75
-80
-85
-90
0.025
Reverse
-95
0
1
2
3
4
-100
100k
Number of 150W Loads
Forward
1M
10M
100M
Frequency (Hz)
Figure 5.
Figure 6.
7
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
OPA690
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
www.ti.com
TYPICAL CHARACTERISTICS: VS = ±5V (continued)
At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω (see Figure 36 for ac performance only), unless otherwise noted.
HARMONIC DISTORTION
vs LOAD RESISTANCE
5MHz HARMONIC DISTORTION
vs SUPPLY VOLTAGE
-60
VO = 2VPP
RL = 100W
f = 5MHz
VO = 2VPP
f = 5MHz
-65
Harmonic Distortion (dBc)
Harmonic Distortion (dBc)
-60
-70
2nd-Harmonic
-75
3rd-Harmonic
-80
-85
-65
2nd-Harmonic
-70
3rd-Harmonic
-75
-80
-90
2.0
1000
100
2.5
3.0
5.0
HARMONIC DISTORTION
vs FREQUENCY
HARMONIC DISTORTION
vs OUTPUT VOLTAGE
5.5
6.0
-60
RL = 100W
f = 5MHz
-60
2nd-Harmonic
-70
-80
3rd-Harmonic
-90
2nd-Harmonic
-65
-70
3rd-Harmonic
-75
-80
-100
0.1
1
10
0.1
20
5
1
Output Voltage Swing (VPP)
Frequency (MHz)
Figure 9.
Figure 10.
HARMONIC DISTORTION
vs NONINVERTING GAIN
HARMONIC DISTORTION
vs INVERTING GAIN
-40
-40
VO = 2VPP
RL = 100W
f = 5MHz
-50
Harmonic Distortion (dBc)
Harmonic Distortion (dBc)
4.5
Figure 8.
VO = 2VPP
RL = 100W
-50
4.0
Figure 7.
Harmonic Distortion (dBc)
Harmonic Distortion (dBc)
-40
3.5
Supply Voltage (±VS)
Load Resistance (W)
-60
2nd-Harmonic
3rd-Harmonic
-70
-80
VO = 2VPP
RL = 100W
f = 5MHz
RF = 1kW
-50
-60
2nd-Harmonic
3rd-Harmonic
-70
-80
-90
1
10
20
1
10
20
Inverting Gain (V/V)
Noninverting Gain (V/V)
Figure 11.
Figure 12.
8
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TYPICAL CHARACTERISTICS: VS = ±5V (continued)
At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω (see Figure 36 for ac performance only), unless otherwise noted.
INPUT VOLTAGE AND CURRENT
NOISE DENSITY
TWO−TONE, 3RD−ORDER
INTERMODULATION SPURIOUS
-30
-35
3rd-Order Spurious Level (dBc)
Voltage Noise (nV/ÖHz)
Current Noise (pA/ÖHz)
100
10
Voltage Noise 5.5nV/ÖHz
Current Noise 3.1pA/ÖHz
50MHz
-40
-45
-50
20MHz
-55
-60
-65
10MHz
Load Power at Matched 50W Load,
see Figure 36
-70
1
-75
100
1k
10k
100k
1M
10M
-8
-6
-4
Frequency (Hz)
0
-2
2
4
Figure 13.
Figure 14.
RECOMMENDED RS
vs CAPACITIVE LOAD
FREQUENCY RESPONSE
vs CAPACITIVE LOAD
8
10
9
80
G = +2
Gain-to-Capacitive Load (dB)
70
60
RS ( W )
6
Single-Tone Load Power (dBm)
50
40
30
20
10
CL = 10pF
6
CL = 100pF
3
CL = 22pF
0
CL = 47pF
-3
VIN
RS
VOUT
OPA690
1kW
CL
402W
-6
402W
1kW is optional.
0
-9
1000
100
0
80
100 120 140 160 180 200
LARGE-SIGNAL
ENABLE/DISABLE RESPONSE
ENABLE/DISABLE
GLITCH
2.0
Output Voltage
1.6
Each Channel
SO-14
Package
Only
1.2
0.8
G = +2
VIN = +1V
4
VDIS
2
0
Output Voltage (10mV/div)
2
6
VDIS (2V/div)
4
0
Output Voltage (0.4V/div)
60
Figure 16.
VDIS
0
40
Figure 15.
6
0.4
20
Frequency (20MHz/div)
Capacitive Load (pF)
VDIS (2V/div)
10
30
20
10
0
-10
Output Voltage
VI = 0V
-20
-30
Time (50ns/div)
Time (20ns/div)
Figure 17.
Figure 18.
9
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TYPICAL CHARACTERISTICS: VS = ±5V (continued)
At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω (see Figure 36 for ac performance only), unless otherwise noted.
OUTPUT VOLTAGE
AND CURRENT LIMITATIONS
1
0
25W
Load Line
50W Load Line
-1
-2
100W Load Line
-3
-200
0
-100
100
200
10
Input Offset Current (IOS)
0
0
-0.5
-10
-1.0
Input Offset Voltage (VOS)
-1.5
-20
-2.0
-50
300
0
-25
25
50
100
Figure 19.
Figure 20.
COMMON−MODE REJECTION RATIO AND
POWER−SUPPLY REJECTION RATIO vs FREQUENCY
SUPPLY AND OUTPUT CURRENTS
vs TEMPERATURE
100
8
250
Sourcing Output Current
-PSRR
90
80
7
CMRR
70
Supply Current (mA)
Power-Supply Rejection Ratio (dB)
Common-Mode Rejection Ratio (dB)
125
Ambient Temperature (°C)
IO (mA)
60
+PSRR
50
40
30
20
200
Sinking Output Current
6
150
5
100
Quiescent Supply Current
4
50
10
0
3
10k
100k
1M
100M
10M
-50
-25
Frequency (MHz)
0
25
50
75
Figure 22.
CLOSED-LOOP OUTPUT IMPEDANCE
vs FREQUENCY
OPEN−LOOP
GAIN AND PHASE
0
60
OPA690
Open-Loop Gain (dB)
200W
ZO
-5V 402W
402W
0.1
0.01
100k
1M
10M
100M
-30
Open-Loop Gain
50
-60
Open-Loop Phase
40
-90
30
-120
20
-150
10
-180
0
-210
-10
-240
-20
10k
0
125
70
+5V
1
100
Ambient Temperature (°C)
Figure 21.
10
Output Impedance ( W )
75
Output Current (mA)
-5
-300
0.5
1W Internal
Power Limit
Output Current Limit
Input Bias Current (IB)
1.0
1k
Frequency (Hz)
10k
100k
1M
10M
100M
Open-Loop Phase (°)
VO (V)
2
-4
20
1.5
3
Input Offset Voltage (mV)
4
2.0
Output Current Limited
1W Internal
Power Limit
Input Bias and Offset Currents (mA)
5
TYPICAL DC DRIFT
OVER TEMPERATURE
-270
1G
Frequency (Hz)
Figure 23.
Figure 24.
10
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TYPICAL CHARACTERISTICS: VS = ±5V (continued)
At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω (see Figure 36 for ac performance only), unless otherwise noted.
5
10
4
8
3
6
2
4
1
Output Voltage
2
0
0
-1
-2
-2
-4
-3
-4
Input Voltage
-5
Output Voltage (V)
Input Voltage (V)
NONINVERTING
OVERDRIVE RECOVERY
-6
-8
-10
Time (10ns/div)
Figure 25.
11
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TYPICAL CHARACTERISTICS: +5V
At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω (see Figure 37 for ac performance only), unless otherwise noted.
SMALL−SIGNAL
FREQUENCY RESPONSE
6
LARGE−SIGNAL
FREQUENCY RESPONSE
9
VO = 0.5VPP
3
6
VO = 3VPP
G = +2
0
3
G = +5
Gain (dB)
Normalized Gain (dB)
VO = 2VPP
G = +1
RF = 25W
-3
VO = 1VPP
0
G = +10
-6
-3
-9
-6
0.7 1
100
10
700
0.5
1
Figure 26.
Figure 27.
SMALL-SIGNAL
PULSE RESPONSE
LARGE-SIGNAL
PULSE RESPONSE
4.1
G = +2
VO = 0.5VPP
2.8
Output Voltage (mV)
2.7
2.6
2.5
2.4
2.3
G = +2
VO = 2VPP
3.7
2.2
3.3
2.9
2.5
2.1
1.7
1.3
2.1
0.9
Time (5ns/div)
Time (5ns/div)
Figure 28.
Figure 29.
RECOMMENDED RS
vs CAPACITIVE LOAD
FREQUENCY RESPONSE
vs CAPACITIVE LOAD
9
50
CL = 10pF
Gain-to-Capacitive Load (dB)
45
40
35
RS ( W )
500
Frequency (MHz)
2.9
Output Voltage (mV)
100
10
Frequency (Hz)
30
25
20
15
10
6
CL = 100pF
3
0
CL = 22pF
+5V
-3
0.1mF
714W
VIN
RS
58W
714W
714W OPA690
VOUT
CL = 47pF
CL
-6
402W +5V
5
402W
-9
0
1
10
100
1000
0
20
40
60
80
100 120
140 160
180 200
Frequency (20MHz/div)
Capacitive Load (pF)
Figure 30.
Figure 31.
12
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SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
TYPICAL CHARACTERISTICS: +5V (continued)
At TA = +25°C, G = +2, RF = 402Ω, and RL = 100Ω (see Figure 37 for ac performance only), unless otherwise noted.
HARMONIC DISTORTION
vs LOAD RESISTANCE
HARMONIC DISTORTION
vs FREQUENCY
-40
-60
Harmonic Distortion (dBc)
Harmonic Distortion (dBc)
VO = 2VPP
f = 5MHz
-65
-70
2nd-Harmonic
3rd-Harmonic
-75
-50
VO = 2VPP
RL = 100W to 2.5V
-60
2nd-Harmonic
-70
-80
3rd-Harmonic
-90
-100
-80
1000
100
0.1
1
Figure 32.
Figure 33.
HARMONIC DISTORTION
vs OUTPUT VOLTAGE
TWO-TONE, 3RD-ORDER
INTERMODULATION SPURIOUS
-60
20
-30
-65
3rd-Order Spurious Level (dBc)
RL = 100W to 2.5V
f = 5MHz
Harmonic Distortion (dBc)
10
Frequency (MHz)
Resistance ( W )
3rd-Harmonic
-70
2nd-Harmonic
-75
-35
50MHz
-40
-45
-50
20MHz
-55
-60
-65
10MHz
-70
Load Power at Matched 50W Load, see Figure 37
-80
-75
0.1
1
3
-14
Output Voltage Swing (VPP)
-12
-10
-8
-6
-4
-2
0
2
Single-Tone Load Power (dBm)
Figure 34.
Figure 35.
13
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APPLICATION INFORMATION
WIDEBAND VOLTAGE-FEEDBACK
OPERATION
The OPA690 provides an exceptional combination of
high output power capability with a wideband,
unity-gain stable voltage-feedback op amp using a
new high slew rate input stage. Typical differential
input stages used for voltage feedback op amps are
designed to steer a fixed-bias current to the
compensation capacitor, setting a limit to the
achievable slew rate. The OPA690 uses a new input
stage which places the transconductance element
between two input buffers, using their output currents
as the forward signal. As the error voltage increases
across the two inputs, an increasing current is
delivered to the compensation capacitor. This
provides very high slew rate (1800V/ms) while
consuming relatively low quiescent current (5.5mA).
This exceptional full-power performance comes at the
price of a slightly higher input noise voltage than
alternative architectures. The 5.5nV/√Hz input voltage
noise for the OPA690 is exceptionally low for this
type of input stage.
Figure 36 shows the dc-coupled, gain of +2, dual
power supply circuit configuration used as the basis
of the ±5V Electrical Characteristics and Typical
Characteristics. For test purposes, the input
impedance is set to 50Ω with a resistor to ground and
the output impedance is set to 50Ω with a series
output resistor. Voltage swings reported in the
specifications are taken directly at the input and
output pins, while output powers (dBm) are at the
matched 50Ω load. For the circuit of Figure 36, the
total effective load will be 100Ω || 804Ω. The disable
control line is typically left open to ensure normal
amplifier operation. Two optional components are
included in Figure 36. An additional resistor (175Ω) is
included in series with the noninverting input.
Combined with the 25Ω dc source resistance looking
back towards the signal generator, this gives an input
bias current cancelling resistance that matches the
200Ω source resistance seen at the inverting input
(see the DC Accuracy and Offset Control section). In
addition to the usual power-supply decoupling
capacitors to ground, a 0.1mF capacitor is included
between the two power-supply pins. In practical
printed
circuit
board
(PCB)
layouts,
this
optional-added capacitor will typically improve the
2nd-harmonic distortion performance by 3dB to 6dB.
Figure 37 shows the ac-coupled, gain of +2,
single-supply circuit configuration which is the basis
of the +5V Electrical Characteristics and Typical
Characteristics. Though not a rail-to-rail design, the
OPA690 requires minimal input and output voltage
headroom compared to other very wideband
voltage-feedback op amps. It will deliver a 3VPP
output swing on a single +5V supply with > 150MHz
bandwidth. The key requirement of broadband
single-supply operation is to maintain input and
output signal swings within the useable voltage
ranges at both the input and the output. The circuit of
Figure 37 establishes an input midpoint bias using a
simple resistive divider from the +5V supply (two
698Ω resistors). The input signal is then ac-coupled
into the midpoint voltage bias. The input voltage can
swing to within 1.5V of either supply pin, giving a
2VPP input signal range centered between the supply
pins. The input impedance matching resistor (59Ω)
used for testing is adjusted to give a 50Ω input load
when the parallel combination of the biasing divider
network is included.
+5V
0.1mF
50W Source
VI
6.8mF
+
175W
DIS
VO
50W
50W
50W Load
OPA690
0.1mF
RF
402W
RG
402W
+
6.8mF
0.1mF
-5V
Figure 36. DC-Coupled, G = +2, Bipolar-Supply
Specification and Test Circuit
+5V
+VS
+
0.1mF
50W Source
0.1mF
VI
59W
6.8mF
698W
50W
698W
DIS
VO
OPA690
100W
VS/2
RF
402W
RG
402W
0.1mF
Figure 37. AC-Coupled, G = +2, Single-Supply
Specification and Test Circuit
14
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Again, an additional resistor (50Ω in this case) is
included directly in series with the noninverting input.
This minimum recommended value provides part of
the dc source resistance matching for the
noninverting input bias current. It is also used to form
a simple parasitic pole to roll off the frequency
response at very high frequencies ( > 500MHz) using
the input parasitic capacitance to form a bandlimiting
pole. The gain resistor (RG) is ac-coupled, giving the
circuit a dc gain of +1, which puts the input dc bias
voltage (2.5V) at the output as well. The output
voltage can swing to within 1V of either supply pin
while delivering > 100mA output current. A
demanding 100Ω load to a midpoint bias is used in
this characterization circuit. The new output stage
circuit used in the OPA690 can deliver large bipolar
output currents into this midpoint load with minimal
crossover distortion, as shown in the +5V supply,
3rd-harmonic distortion plots.
The OPA690 in the circuit of Figure 39 provides
> 200MHz bandwidth for a 2VPP output swing.
Minimal 3rd-harmonic distortion or two-tone,
3rd-order intermodulation distortion will be observed
due to the very low crossover distortion in the
OPA690 output stage. The limit of output
Spurious-Free Dynamic Range (SFDR) will be set by
the 2nd-harmonic distortion. Without RB, the circuit of
Figure 39 measured at 10MHz shows an SFDR of
57dBc. This may be improved by pulling additional dc
bias current (IB) out of the output stage through the
optional RB resistor to ground (the output midpoint is
at 2.5V for Figure 39). Adjusting IB gives the
improvement in SFDR shown in Figure 38. SFDR
improvement is achieved for IB values up to 5mA,
with worse performance for higher values.
70
VO = 2VPP, 10MHz
68
66
SINGLE-SUPPLY ADC INTERFACE
SFDR (dBc)
64
Most modern, high performance ADCs (such as the
TI ADS8xx and ADS9xx series) operate on a single
+5V (or lower) power supply. It has been a
considerable challenge for single-supply op amps to
deliver a low distortion input signal at the ADC input
for signal frequencies exceeding 5MHz. The high
slew rate, exceptional output swing, and high linearity
of the OPA690 make it an ideal single-supply ADC
driver. The circuit on the front page shows one
possible (inverting) interface. Figure 39 shows the
test circuit of Figure 37 modified for a capacitive
(ADC) load and with an optional output pull-down
resistor (RB).
62
60
58
56
54
52
50
0
1
2
3
4
5
6
7
8
9
10
Output Pull-Down Current (mA)
Figure 38. SFDR vs IB
+5V
Power- supply decoupling not shown.
698W
DIS
0.1mF
50W
RS
30W
VI
1VPP
2.5V DC
±1V AC
OPA690
59W
698W
50pF
ADC Input
402W
402W
RB
0.1mF
IB
Figure 39. SFDR versus IB Test Circuit
15
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HIGH-PERFORMANCE DAC
TRANSIMPEDANCE AMPLIFIER
The 5pF capacitor in the feedback loop provides
added bandwidth control for the signal path.
High-frequency, direct digital synthesis (DDS)
Digital-to-Analog Converters (DACs) require a low
distortion output amplifier to retain their SFDR
performance into real-world loads. See Figure 40 for
a single-ended output drive implementation. In this
circuit, only one side of the complementary output
drive signal is used. The diagram shows the signal
output current connected into the virtual ground
summing junction of the OPA690, which is set up as
a transimpedance stage or I-V converter. The unused
current output of the DAC is connected to ground. If
the DAC requires that its outputs terminate to a
compliance voltage other than ground for operation,
the appropriate voltage level may be applied to the
noninverting input of the OPA690. The dc gain for this
circuit is equal to RF. At high frequencies, the DAC
output capacitance will produce a zero in the noise
gain for the OPA690 that may cause peaking in the
closed-loop frequency response. CF is added across
RF to compensate for this noise gain peaking. To
achieve a flat transimpedance frequency response,
the pole in the feedback network should be set to:
1
=
2pRFCF
GBP
4pRFCD
which will give a closed-loop
bandwidth, f−3dB, of approximately:
f-3dB =
GBP
2pRFCD
50W
OPA690
High-Speed
DAC
VO = IO RF
RF
CF
CD
IO
IO
Figure 40. DAC Transimpedance Amplifier
+12V
(1)
2kW
transimpedance
8VPP 50W
4VPP
OPA690
0.1mF
2kW
50W
Load
(2)
Where GBP = gain bandwidth product (Hz) for the
OPA690.
HIGH-POWER LINE DRIVER
The large output swing capability of the OPA690 and
its high current capability allow it to drive a 50Ω line
with a peak-to-peak signal up to 4VPP at the load, or
8VPP at the output of the amplifier using a single 12V
supply. Figure 41 shows such a circuit set for a gain
of 8 to the output or 4 to the load.
1VPP
50W
Source
50W
400W
5pF
Figure 41. High-Power Coax Line Driver
16
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SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
SINGLE-SUPPLY ACTIVE FILTERS
The high bandwidth provided by the OPA690, while
operating on a single +5V supply, lends itself well to
high-frequency active filter designs. Again, the key
additional requirement is to establish the dc operating
point of the signal near the supply midpoint for
highest dynamic range. See Figure 42 for an example
design of a 5MHz low-pass Butterworth filter using
the Sallen-Key topology.
Both the input signal and the gain setting resistor are
ac-coupled using 0.1mF blocking capacitors (actually
giving bandpass response with the low-frequency
pole set to 32kHz for the component values shown).
As discussed for Figure 37, this allows the midpoint
bias formed by the two 1.87kΩ resistors to appear at
both the input and output pins. The midband signal
gain is set to +4 (12dB) in this case. The capacitor to
ground on the noninverting input is intentionally set
larger to dominate input parasitic terms. At a gain of
+4, the OPA690 on a single supply will show ~80MHz
small- and large-signal bandwidth. The resistor
values have been slightly adjusted to account for this
limited bandwidth in the amplifier stage. Tests of this
circuit show a precise 5MHz, −3dB point with a
maximally flat passband (above the 32kHz
ac-coupling corner), and a maximum stop band
attenuation of 36dB at the amplifier’s −3dB bandwidth
of 80MHz.
+5V
5MHz, 2nd-Order Butterworth Filter Response
15
1.87kW
100pF
10
137W
DIS
432W
VI
4VI
OPA690
1.87kW
150pF
5MHz, 2nd-Order
Butterworth Filter
Gain (dB)
0.1mF
5
0
1.5kW
-5
100k
500W
1M
10M
Frequency (Hz)
0.1mF
Figure 42. Single-Supply, High-Frequency Active Filter
17
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DESIGN-IN TOOLS
DEMONSTRATION FIXTURES
Two printed circuit boards (PCBs) are available to
assist in the initial evaluation of circuit performance
using the OPA690 in its two package options. Both of
these are offered free of charge as unpopulated
PCBs, delivered with a user’s guide. The summary
information for these fixtures is shown in Table 1.
Table 1. Demonstration Fixtures by Package
PRODUCT
PACKAGE
ORDERING
NUMBER
LITERATURE
NUMBER
OPA690ID
SO-8
DEM-OPA-SO-1A
SBOU009
OPA690IDBV
SOT23-6
DEM-OPA-SOT-1A
SBOU010
The demonstration fixtures can be requested at the
Texas Instruments web site (www.ti.com) through the
OPA690 product folder.
MACROMODELS AND APPLICATIONS
SUPPORT
Computer simulation of circuit performance using
SPICE is often useful when analyzing the
performance of analog circuits and systems. This is
particularly true for video and RF amplifier circuits
where parasitic capacitance and inductance can have
a major effect on circuit performance. A SPICE model
for the OPA690 is available through the OPA690
product folder under Simulation Models. These
models do a good job of predicting small-signal ac
and transient performance under a wide variety of
operating conditions. They do not do as well in
predicting the harmonic distortion or dG/dP
characteristics. These models do not attempt to
distinguish between the package types in their
small-signal ac performance.
18
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SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
OPERATING SUGGESTIONS
OPTIMIZING RESISTOR VALUES
Since the OPA690 is a unity-gain stable,
voltage-feedback op amp, a wide range of resistor
values may be used for the feedback and gain setting
resistors. The primary limits on these values are set
by dynamic range (noise and distortion) and parasitic
capacitance considerations. For a noninverting
unity-gain follower application, the feedback
connection should be made with a 25Ω resistor, not a
direct short. This will isolate the inverting input
capacitance from the output pin and improve the
frequency response flatness. Usually, for G > 1
applications, the feedback resistor value should be
between 200Ω and 1.5kΩ. Below 200Ω, the feedback
network will present additional output loading which
can degrade the harmonic distortion performance of
the OPA690. Above 1.5kΩ, the typical parasitic
capacitance (approximately 0.2pF) across the
feedback
resistor
may
cause
unintentional
band-limiting in the amplifier response.
A good rule of thumb is to target the parallel
combination of RF and RG (see Figure 36) to be less
than approximately 300Ω. The combined impedance
RF || RG interacts with the inverting input capacitance,
placing an additional pole in the feedback network
and thus, a zero in the forward response. Assuming a
2pF total parasitic on the inverting node, holding RF ||
RG < 300Ω will keep this pole above 250MHz. By
itself, this constraint implies that the feedback resistor
RF can increase to several kΩ at high gains. This is
acceptable as long as the pole formed by RF and any
parasitic capacitance appearing in parallel is kept out
of the frequency range of interest.
BANDWIDTH VERSUS GAIN: NONINVERTING
OPERATION
Voltage-feedback op amps exhibit decreasing
closed-loop bandwidth as the signal gain is
increased. In theory, this relationship is described by
the Gain Bandwidth Product (GBP) shown in the
Electrical Characteristics. Ideally, dividing GBP by the
noninverting signal gain (also called the Noise Gain,
or NG) will predict the closed-loop bandwidth. In
practice, this only holds true when the phase margin
approaches 90°, as it does in high gain
configurations. At low gains (increased feedback
factors), most amplifiers will exhibit a more complex
response with lower phase margin. The OPA690 is
compensated to give a slightly peaked response in a
noninverting gain of 2 (see Figure 36). This results in
a typical gain of +2 bandwidth of 220MHz, far
exceeding that predicted by dividing the 300MHz
GBP by 2. Increasing the gain will cause the phase
margin to approach 90° and the bandwidth to more
closely approach the predicted value of (GBP/NG). At
a gain of +10, the 30MHz bandwidth shown in the
Electrical Characteristics agrees with that predicted
using the simple formula and the typical GBP of
300MHz.
The frequency response in a gain of +2 may be
modified to achieve exceptional flatness simply by
increasing the noise gain to 2.5. One way to do this,
without affecting the +2 signal gain, is to add an
804Ω resistor across the two inputs in the circuit of
Figure 36. A similar technique may be used to reduce
peaking in unity-gain (voltage follower) applications.
For example, by using a 402Ω feedback resistor
along with a 402Ω resistor across the two op amp
inputs, the voltage follower response will be similar to
the gain of +2 response of Figure 37. Reducing the
value of the resistor across the op amp inputs will
further limit the frequency response due to increased
noise gain.
The OPA690 exhibits minimal bandwidth reduction
going to single-supply (+5V) operation as compared
with ±5V. This is because the internal bias control
circuitry retains nearly constant quiescent current as
the total supply voltage between the supply pins is
changed.
19
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SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
www.ti.com
INVERTING AMPLIFIER OPERATION
Since the OPA690 is a general-purpose, wideband
voltage-feedback op amp, all of the familiar op amp
application circuits are available to the designer.
Inverting operation is one of the more common
requirements and offers several performance
benefits. Figure 43 shows a typical inverting
configuration where the I/O impedances and signal
gain from Figure 36 are retained in an inverting circuit
configuration.
+5V
+
0.1mF
6.8mF
0.1mF
DIS
RB
146W
50W
Source
RO
50W
OPA690
50W Load
RG
200W
RF
402W
RM
67W
0.1mF
+
6.8mF
-5V
Figure 43. Gain of –2 Example Circuit
In the inverting configuration, three key design
considerations must be noted. The first is that the
gain resistor (RG) becomes part of the signal channel
input impedance. If input impedance matching is
desired (which is beneficial whenever the signal is
coupled through a cable, twisted-pair, long PCB
trace, or other transmission line conductor), RG may
be set equal to the required termination value and RF
adjusted to give the desired gain. This is the simplest
approach and results in optimum bandwidth and
noise performance. However, at low inverting gains,
the resultant feedback resistor value can present a
significant load to the amplifier output. For an
inverting gain of 2, setting RG to 50Ω for input
matching eliminates the need for RM but requires a
100Ω feedback resistor. This has the interesting
advantage that the noise gain becomes equal to 2 for
a 50Ω source impedance—the same as the
noninverting circuits considered in the previous
section. The amplifier output, however, will now see
the 100Ω feedback resistor in parallel with the
external load. In general, the feedback resistor should
be limited to the 200Ω to 1.5kΩ range. In this case, it
is preferable to increase both the RF and RG values,
as shown in Figure 43, and then achieve the input
matching impedance with a third resistor (RM) to
ground. The total input impedance becomes the
parallel combination of RG and RM.
The second major consideration, touched on in the
previous paragraph, is that the signal source
impedance becomes part of the noise gain equation
and influences the bandwidth. For the example in
Figure 43, the RM value combines in parallel with the
external 50Ω source impedance, yielding an effective
driving impedance of 50Ω || 67Ω = 28.6Ω. This
impedance is added in series with RG for calculating
the noise gain (NG). The resultant NG is 2.8 for
Figure 43, as opposed to only 2 if RM could be
eliminated as discussed above. The bandwidth will
therefore be slightly lower for the gain of ±2 circuit of
Figure 43 than for the gain of +2 circuit of Figure 36.
The third important consideration in inverting amplifier
design is setting the bias current cancellation resistor
on the noninverting input (RB). If this resistor is set
equal to the total dc resistance looking out of the
inverting node, the output dc error, due to the input
bias currents, will be reduced to (Input Offset Current)
× RF. If the 50Ω source impedance is dc-coupled in
Figure 43, the total resistance to ground on the
inverting input will be 228Ω. Combining this in parallel
with the feedback resistor gives the RB = 146Ω used
in this example. To reduce the additional
high-frequency noise introduced by this resistor, it is
sometimes bypassed with a capacitor. As long as RB
< 350Ω, the capacitor is not required because the
total noise contribution of all other terms will be less
than that of the op amp input noise voltage. As a
minimum, the OPA690 requires an RB value of 50Ω
to damp out parasitic-induced peaking—a direct short
to ground on the noninverting input runs the risk of a
very high-frequency instability in the input stage.
20
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www.ti.com
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
OUTPUT CURRENT AND VOLTAGE
The OPA690 provides output voltage and current
capabilities that are unsurpassed in a low-cost
monolithic op amp. Under no-load conditions at
+25°C, the output voltage typically swings closer than
1V to either supply rail; the specified swing limit is
within 1.2V of either rail. Into a 15Ω load (the
minimum tested load), it will deliver more than
±160mA.
The specifications described previously, though
familiar in the industry, consider voltage and current
limits separately. In many applications, it is the
voltage × current, or V-I product, which is more
relevant to circuit operation. Refer to Figure 19, the
Output Voltage and Current Limitations plot in the
Typical Characteristics. The X- and Y-axes of this
graph show the zero-voltage output current limit and
the zero-current output voltage limit, respectively. The
four quadrants give a more detailed view of the
OPA690 output drive capabilities, noting that the
graph is bounded by a Safe Operating Area of 1W
maximum internal power dissipation. Superimposing
resistor load lines onto the plot shows that the
OPA690 can drive ±2.5V into 25Ω or ±3.5V into 50Ω
without exceeding the output capabilities or the 1W
dissipation limit. A 100Ω load line (the standard test
circuit load) shows the full ±3.9V output swing
capability, as shown in the typical specifications.
The minimum specified output voltage and current
specifications over temperature are set by worst-case
simulations at the cold temperature extreme. Only at
cold startup will the output current and voltage
decrease to the numbers shown in the Electrical
Characteristic tables. As the output transistors deliver
power, their junction temperatures increase,
decreasing their VBEs (increasing the available output
voltage swing) and increasing their current gains
(increasing the available output current). In
steady-state operation, the available output voltage
and current is always greater than that shown in the
over-temperature specifications because the output
stage junction temperatures will be higher than the
minimum specified operating ambient.
OPA690 can be very susceptible to decreased
stability and closed-loop response peaking when a
capacitive load is placed directly on the output pin.
When the amplifier's open-loop output resistance is
considered, this capacitive load introduces an
additional pole in the signal path that can decrease
the phase margin. Several external solutions to this
problem have been suggested. When the primary
considerations are frequency response flatness,
pulse response fidelity, and/or distortion, the simplest
and most effective solution is to isolate the capacitive
load from the feedback loop by inserting a
series-isolation resistor between the amplifier output
and the capacitive load. This does not eliminate the
pole from the loop response, but rather shifts it and
adds a zero at a higher frequency. The additional
zero acts to cancel the phase lag from the capacitive
load pole, thus increasing the phase margin and
improving stability.
The Typical Characteristics show the recommended
RS versus capacitive load (Figure 15 for ±5V and
Figure 30 for +5V) and the resulting frequency
response at the load. Parasitic capacitive loads
greater than 2pF can begin to degrade the
performance of the OPA690. Long PCB traces,
unmatched cables, and connections to multiple
devices can easily exceed this value. Always
consider this effect carefully, and add the
recommended series resistor as close as possible to
the OPA690 output pin (see the Board Layout
Guidelines section).
The criterion for setting this RS resistor is a maximum
bandwidth, flat frequency response at the load. For
the OPA690 operating in a gain of +2, the frequency
response at the output pin is already slightly peaked
without the capacitive load requiring relatively high
values of RS to flatten the response at the load.
Increasing the noise gain will reduce the peaking as
described previously. The circuit of Figure 44
demonstrates this technique, allowing lower values of
RS to be used for a given capacitive load.
+5V
50W
To protect the output stage from accidental shorts to
ground and the power supplies, output short-circuit
protection is included in the OPA690. The circuit acts
to limit the maximum source or sink current to
approximately 250mA.
175W
50W
RNG
Power-supply
decoupling not shown.
R
VO
OPA690
402W
CL
DRIVING CAPACITIVE LOADS
One of the most demanding and yet very common
load conditions for an op amp is capacitive loading.
Often, the capacitive load is the input of an
ADC—including additional external capacitance which
may be recommended to improve ADC linearity. A
high-speed, high open-loop gain amplifier like the
402W
-5V
Figure 44. Capacitive Load Driving with Noise
Gain Tuning
21
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SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
www.ti.com
This gain of +2 circuit includes a noise gain tuning
resistor across the two inputs to increase the noise
gain, increasing the unloaded phase margin for the
op amp. Although this technique will reduce the
required RS resistor for a given capacitive load, it
does increase the noise at the output. It also will
decrease the loop gain, slightly decreasing the
distortion performance. If, however, the dominant
distortion mechanism arises from a high RS value,
significant dynamic range improvement can be
achieved using this technique. Figure 45 shows the
required RS versus CLOAD parametric on noise gain
using this technique. This is the circuit of Figure 44
with RNG adjusted to increase the noise gain
(increasing the phase margin) then sweeping CLOAD
and finding the required RS to get a flat frequency
response. This plot also gives the required RS versus
CLOAD for the OPA690 operated at higher signal
gains.
100
90
80
RS (W)
70
NG = 2
In most op amps, increasing the output voltage swing
increases harmonic distortion directly. The new
output stage used in the OPA690 actually holds the
difference between fundamental power and the 2ndand 3rd-harmonic powers relatively constant with
increasing output power until very large output swings
are required ( > 4VPP). This also shows up in the
2-tone, 3rd-order intermodulation spurious (IM3)
response curves. The 3rd-order spurious levels are
moderately low at low output power levels. The
output stage continues to hold them low even as the
fundamental power reaches very high levels. As the
Typical
Characteristics
show,
the
spurious
intermodulation powers do not increase as predicted
by a traditional intercept model. As the fundamental
power level increases, the dynamic range does not
decrease significantly. For two tones centered at
20MHz, with 10dBm/tone into a matched 50Ω load
(that is, 2VPP for each tone at the load, which requires
8VPP for the overall two-tone envelope at the output
pin), the Typical Characteristics show 47dBc
difference between the test tone powers and the
3rd-order intermodulation spurious powers. This
performance improves further when operating at
lower frequencies.
60
50
NOISE PERFORMANCE
40
30
20
NG = 3
10
NG = 4
0
1
10
100
1000
Capacitive Load (pF)
Figure 45. Required RS vs Noise Gain
DISTORTION PERFORMANCE
The OPA690 provides good distortion performance
into a 100Ω load on ±5V supplies. Relative to
alternative solutions, it provides exceptional
performance into lighter loads and/or operating on a
single +5V supply. Generally, until the fundamental
signal reaches very high frequency or power levels,
the 2nd-harmonic dominates the distortion with a
negligible 3rd-harmonic component. Focusing then on
the 2nd-harmonic, increasing the load impedance
improves distortion directly. Remember that the total
load includes the feedback network; in the
noninverting configuration (see Figure 36), this is sum
of RF + RG, while in the inverting configuration it is
just
RF.
Also,
providing
an
additional
supply-decoupling capacitor (0.1µF) between the
supply pins (for bipolar operation) improves the
2nd-order distortion slightly (3dB to 6dB).
High slew rate, unity-gain stable, voltage-feedback op
amps usually achieve their slew rate at the expense
of a higher input noise voltage. The 5.5nV/√Hz input
voltage noise for the OPA690 is, however, much
lower than comparable amplifiers. The input-referred
voltage noise, and the two input-referred current
noise terms, combine to give low output noise under
a wide variety of operating conditions. Figure 46
shows the op amp noise analysis model with all the
noise terms included. In this model, all noise terms
are taken to be noise voltage or current density terms
in either nV/√Hz or pA/√Hz.
ENI
OPA690
RS
EO
IBN
ERS
RF
Ö4kTRS
4kT
RG
RG
IBI
Ö4kTRF
4kT = 1.6E - 20J
at 290°K
Figure 46. Op Amp Noise Analysis Model
22
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SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
The total output spot noise voltage can be computed
as the square root of the sum of all squared output
noise voltage contributors. Equation 3 shows the
general form for the output noise voltage using the
terms shown in Figure 46.
EO =
ENI2 + (IBNRS)2 + 4kTRS NG2 + (IBIRF)2 + 4kTRFNG
(3)
Dividing this expression by the noise gain [NG = (1 +
RF/RG)] will give the equivalent input-referred spot
noise voltage at the noninverting input, as shown in
Equation 4.
EN =
ENI2 + (IBNRS)2 + 4kTRS +
IBIRF
NG
2
+
4kTRF
NG
(4)
Evaluating these two equations for the OPA690
circuit and component values (see Figure 36) gives a
total output spot noise voltage of 12.3nV/√Hz and a
total equivalent input spot noise voltage of 6.1nV/√Hz.
This is including the noise added by the bias current
cancellation resistor (175Ω) on the noninverting input.
This total input-referred spot noise voltage is only
slightly higher than the 5.5nV/√Hz specification for the
op amp voltage noise alone. This will be the case as
long as the impedances appearing at each op amp
input are limited to the previously recommend
maximum value of 300Ω. Keeping both (RF || RG) and
the noninverting input source impedance less than
300Ω will satisfy both noise and frequency response
flatness considerations. Since the resistor-induced
noise is relatively negligible, additional capacitive
decoupling across the bias current cancellation
resistor (RB) for the inverting op amp configuration of
Figure 43 is not required.
–(NG = noninverting signal gain)
±(NG × VOS(MAX)) ± (RF × IOS(MAX))
= ±(2 × 4mV) ± (402Ω × 1mA)
= ±8.4mV
A fine-scale output offset null, or dc operating point
adjustment, is often required. Numerous techniques
are available for introducing dc offset control into an
op amp circuit. Most of these techniques eventually
reduce to adding a dc current through the feedback
resistor. In selecting an offset trim method, one key
consideration is the impact on the desired signal path
frequency response. If the signal path is intended to
be noninverting, the offset control is best applied as
an inverting summing signal to avoid interaction with
the signal source. If the signal path is intended to be
inverting, applying the offset control to the
noninverting input may be considered. However, the
dc offset voltage on the summing junction will set up
a dc current back into the source that must be
considered. Applying an offset adjustment to the
inverting op amp input can change the noise gain and
frequency response flatness. For a dc-coupled
inverting amplifier, see Figure 47 for one example of
an offset adjustment technique that has minimal
impact on the signal frequency response. In this
case, the dc offsetting current is brought into the
inverting input node through resistor values that are
much larger than the signal path resistors. This
ensures that the adjustment circuit has minimal effect
on the loop gain and hence, the frequency response.
+5V
Power-supply decoupling
not shown.
OPA690
VO
328W
0.1mF
DC ACCURACY AND OFFSET CONTROL
The balanced input stage of a wideband
voltage-feedback op amp allows good output dc
accuracy in a wide variety of applications. The
power-supply current trim for the OPA690 gives even
tighter control than comparable amplifiers. Although
the high-speed input stage does require relatively
high input bias current (typically ±8µA at each input
terminal), the close matching between them may be
used to reduce the output dc error caused by this
current. The total output offset voltage may be
considerably reduced by matching the dc source
resistances appearing at the two inputs. This reduces
the output dc error due to the input bias currents to
the offset current times the feedback resistor.
Evaluating the configuration of Figure 36, and using
worst-case +25°C input offset voltage and current
specifications, gives a worst-case output offset
voltage equal to:
BLANKSPACE
BLANKSPACE
-5V
RG
500W
+5V
5kW
RF
1kW
VI
20kW
±200mV Output Adjustment
10kW
0.1mF
5kW
VO
VI
=-
RF
RG
= -2
-5V
Figure 47. DC-Coupled, Inverting Gain of -2, with
Offset Adjustment
23
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Product Folder Link(s): OPA690
OPA690
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
DISABLE OPERATION
The OPA690 provides an optional disable feature that
may be used either to reduce system power or to
implement a simple channel multiplexing operation. If
the DIS control pin is left unconnected, the OPA690
will operate normally. To disable, the control pin must
be asserted LOW. Figure 48 shows a simplified
internal circuit for the disable control feature.
+VS
IS
Control
-VS
Figure 48. Simplified Disable Control Circuit
In normal operation, base current to Q1 is provided
through the 110kΩ resistor, while the emitter current
through the 15kΩ resistor sets up a voltage drop that
is inadequate to turn on the two diodes in Q1's
emitter. As VDIS is pulled LOW, additional current is
pulled through the 15kΩ resistor, eventually turning
on those two diodes (≈75µA). At this point, any
further current pulled out of VDIS goes through those
diodes holding the emitter-base voltage of Q1 at
approximately 0V. This shuts off the collector current
out of Q1, turning the amplifier off. The supply current
in the disable mode are only those required to
operate the circuit of Figure 48. Additional circuitry
ensures that turn-on time occurs faster than turn-off
time (make-before-break).
When disabled, the output and input nodes go to a
high-impedance state. If the OPA690 is operating at a
6
4
VDIS
2
0
VDIS (2V/div)
110kW
The transition edge rate (dV/dt) of the DIS control line
will influence this glitch. For the plot of Figure 49, the
edge rate was reduced until no further reduction in
glitch amplitude was observed. This approximately
1V/ns maximum slew rate may be achieved by
adding a simple RC filter into the DIS pin from a
higher speed logic line. If extremely fast transition
logic is used, a 1kΩ series resistor between the logic
gate and the DIS input pin provides adequate
bandlimiting using just the parasitic input capacitance
on the DIS pin while still ensuring adequate logic
level swing.
Output Voltage (10mV/div)
Q1
VDIS
gain of +1, this will show a very high impedance at
the output and exceptional signal isolation. If
operating at a gain greater than +1, the total
feedback network resistance (RF + RG) will appear as
the impedance looking back into the output, but the
circuit will still show very high forward and reverse
isolation. If configured as an inverting amplifier, the
input and output will be connected through the
feedback network resistance (RF + RG) and the
isolation will be very poor as a result.
One key parameter in disable operation is the output
glitch when switching in and out of the disabled
mode. Figure 49 shows these glitches for the circuit
of Figure 36 with the input signal at 0V. The glitch
waveform at the output pin is plotted along with the
DIS pin voltage.
15kW
25kW
www.ti.com
30
20
10
Output Voltage
0
VI = 0V
-10
-20
-30
Time (20ns/div)
Figure 49. Disable/Enable Glitch
24
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OPA690
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SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
THERMAL ANALYSIS
Due to the high output power capability of the
OPA690, heatsinking or forced airflow may be
required under extreme operating conditions.
Maximum desired junction temperature will set the
maximum allowed internal power dissipation as
described below. In no case should the maximum
junction temperature be allowed to exceed 175°C.
Operating junction temperature (TJ) is given by TA +
PD × qJA. The total internal power dissipation (PD) is
the sum of quiescent power (PDQ) and additional
power dissipated in the output stage (PDL) to deliver
load power. Quiescent power is simply the specified
no-load supply current times the total supply voltage
across the part. PDL depends on the required output
signal and load but, for a grounded resistive load, be
at a maximum when the output is fixed at a voltage
equal to 1/2 of either supply voltage (for equal bipolar
supplies). Under this condition, PDL = VS2/(4 × RL)
where RL includes feedback network loading.
As a worst-case example, compute the maximum TJ
using an OPA690IDBV (SOT23-6 package) in the
circuit of Figure 36 operating at the maximum
specified ambient temperature of +85°C and driving a
grounded 20Ω load.
PD = 10V × 6.2mA + 52/(4 × (20Ω || 804Ω)) = 382mW
Maximum TJ = +85°C + (0.38W × 150°C/W) = 142°C.
Although this is still well below the specified
maximum junction temperature, system reliability
considerations may require lower tested junction
temperatures. The highest possible internal
dissipation will occur if the load requires current to be
forced into the output for positive output voltages or
sourced from the output for negative output voltages.
This puts a high current through a large internal
voltage drop in the output transistors. Figure 19, the
output V-I plot shown in the ±5V Typical
Characteristics, include a boundary for 1W maximum
internal power dissipation under these conditions.
Note that it is the power in the output stage and not
into the load that determines internal power
dissipation.
25
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SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
www.ti.com
BOARD LAYOUT GUIDELINES
Achieving
optimum
performance
with
a
high-frequency amplifier like the OPA690 requires
careful attention to board layout parasitics and
external component types. Recommendations that
will optimize performance include:
a. Minimize parasitic capacitance to any ac
ground for all of the signal I/O pins. Parasitic
capacitance on the output and inverting input pins
can cause instability: on the noninverting input, it
can react with the source impedance to cause
unintentional bandlimiting. To reduce unwanted
capacitance, a window around the signal I/O pins
should be opened in all of the ground and power
planes around those pins. Otherwise, ground and
power planes should be unbroken elsewhere on
the board.
b. Minimize the distance (< 0.25") from the
power-supply pins to high-frequency 0.1mF
decoupling capacitors. At the device pins, the
ground and power-plane layout should not be in
close proximity to the signal I/O pins. Avoid
narrow power and ground traces to minimize
inductance between the pins and the decoupling
capacitors. The power-supply connections should
always be decoupled with these capacitors. An
optional supply decoupling capacitor (0.1mF)
across the two power supplies (for bipolar
operation) will improve 2nd-harmonic distortion
performance. Larger (2.2mF to 6.8mF) decoupling
capacitors, effective at lower frequencies, should
also be used on the main supply pins. These may
be placed somewhat farther from the device and
may be shared among several devices in the
same area of the PCB.
c. Careful selection and placement of external
components will preserve the high-frequency
performance of the OPA690. Resistors should
be a very low reactance type. Surface-mount
resistors work best and allow a tighter overall
layout. Metal film or carbon composition
axially-leaded resistors can also provide good
high-frequency performance. Again, keep their
leads and PCB traces as short as possible. Never
use wirewound type resistors in a high-frequency
application. Since the output pin and inverting
input pin are the most sensitive to parasitic
capacitance, always position the feedback and
series output resistor, if any, as close as possible
to the output pin. Other network components,
such as noninverting input termination resistors,
should also be placed close to the package.
Where double-side component mounting is
allowed, place the feedback resistor directly
under the package on the other side of the board
between the output and inverting input pins. Even
with a low parasitic capacitance shunting the
external resistors, excessively high resistor
values can create significant time constants that
can degrade performance. Good axial metal film
or surface-mount resistors have approximately
0.2pF in shunt with the resistor. For resistor
values > 1.5kΩ, this parasitic capacitance can
add a pole and/or zero below 500MHz that can
affect circuit operation. Keep resistor values as
low as possible consistent with load driving
considerations. The 402Ω feedback used in the
Electrical Characteristics is a good starting point
for design. Note that a 25Ω feedback resistor,
rather than a direct short, is suggested for the
unity-gain follower application. This effectively
isolates the inverting input capacitance from the
output pin that would otherwise cause an
additional peaking in the gain of +1 frequency
response.
d. Connections to other wideband devices on the
board may be made with short, direct traces or
through onboard transmission lines. For short
connections, consider the trace and the input to
the next device as a lumped capacitive load.
Relatively wide traces (50mils or 1,27mm to
100mils or 2,54mm) should be used, preferably
with ground and power planes opened up around
them. Estimate the total capacitive load and set
RS from the plot of Recommended RS vs
Capacitive Load (Figure 15 for ±5V and Figure 30
for +5V). Low parasitic capacitive loads (< 5pF)
may not need an RS because the OPA690 is
nominally compensated to operate with a 2pF
parasitic load. Higher parasitic capacitive loads
without an RS are allowed as the signal gain
increases (increasing the unloaded phase
margin). If a long trace is required, and the 6dB
signal loss intrinsic to a doubly-terminated
transmission line is acceptable, implement a
matched impedance transmission line using
microstrip or stripline techniques (consult an ECL
design handbook for microstrip and stripline
layout techniques). A 50Ω environment is
normally not necessary on board, and in fact, a
higher impedance environment will improve
distortion as shown in the distortion versus load
plots. With a characteristic board trace
impedance defined (based on board material and
trace dimensions), a matching series resistor into
the trace from the output of the OPA690 is used
as well as a terminating shunt resistor at the input
of the destination device. Remember also that the
terminating impedance will be the parallel
combination of the shunt resistor and the input
impedance of the destination device; this total
effective impedance should be set to match the
trace impedance. The high output voltage and
current capability of the OPA690 allows multiple
26
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
OPA690
www.ti.com
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
destination devices to be handled as separate
transmission lines, each with their own series and
shunt terminations. If the 6dB attenuation of a
doubly-terminated
transmission
line
is
unacceptable,
a
long
trace
can
be
series-terminated at the source end only. Treat
the trace as a capacitive load in this case and set
the series resistor value as shown in the plot of
Recommended RS vs Capacitive Load (Figure 15
for ±5V and Figure 30 for +5V). This will not
preserve signal integrity as well as a
doubly-terminated line. If the input impedance of
the destination device is low, there will be some
signal attenuation due to the voltage divider
formed by the series output into the terminating
impedance.
e. Socketing a high-speed part like the OPA690
is not recommended. The additional lead length
and pin-to-pin capacitance introduced by the
socket can create an extremely troublesome
parasitic network which can make it almost
impossible to achieve a smooth, stable frequency
response. Best results are obtained by soldering
the OPA690 onto the board.
INPUT AND ESD PROTECTION
The OPA690 is built using a very high-speed
complementary bipolar process. The internal junction
breakdown voltages are relatively low for these very
small geometry devices. These breakdowns are
reflected in the Absolute Maximum Ratings table. All
device pins are protected with internal ESD protection
diodes to the power supplies, as shown in Figure 50.
+VCC
External
Pin
Internal
Circuitry
-VCC
Figure 50. Internal ESD Protection
These diodes provide moderate protection to input
overdrive voltages above the supplies as well. The
protection diodes can typically support 30mA
continuous current. Where higher currents are
possible (e.g., in systems with ±15V supply parts
driving into the OPA690), current-limiting series
resistors should be added into the two inputs. Keep
these resistor values as low as possible since high
values degrade both noise performance and
frequency response.
27
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
OPA690
SBOS223F – DECEMBER 2001 – REVISED FEBRUARY 2010
www.ti.com
REVISION HISTORY
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision E (November 2008) to Revision F
Page
•
Changed data sheet format to current standards ................................................................................................................. 1
•
Deleted Lead Temperature specification from Absolute Maximum Ratings table ................................................................ 2
•
Added Figure 25, Noninverting Overdrive Recovery plot ................................................................................................... 11
Changes from Revision D (August 2008) to Revision E
•
Page
Deleted obsolete OPA680 from Related Products table ...................................................................................................... 1
28
Copyright © 2001–2010, Texas Instruments Incorporated
Product Folder Link(s): OPA690
PACKAGE OPTION ADDENDUM
www.ti.com
11-Apr-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Top-Side Markings
(3)
(4)
OPA690ID
ACTIVE
SOIC
D
8
75
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
OPA
690
OPA690IDBVR
ACTIVE
SOT-23
DBV
6
3000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
OAEI
OPA690IDBVRG4
ACTIVE
SOT-23
DBV
6
3000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
OAEI
OPA690IDBVT
ACTIVE
SOT-23
DBV
6
250
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
OAEI
OPA690IDBVTG4
ACTIVE
SOT-23
DBV
6
250
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
OAEI
OPA690IDG4
ACTIVE
SOIC
D
8
75
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
OPA
690
OPA690IDR
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
OPA
690
OPA690IDRG4
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
OPA
690
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
11-Apr-2013
(4)
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a
continuation of the previous line and the two combined represent the entire Top-Side Marking for that device.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
26-Jan-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
OPA690IDBVR
SOT-23
DBV
6
3000
180.0
OPA690IDBVT
SOT-23
DBV
6
250
OPA690IDR
SOIC
D
8
2500
B0
(mm)
K0
(mm)
P1
(mm)
8.4
3.2
3.1
1.39
4.0
180.0
8.4
3.2
3.1
1.39
330.0
12.4
6.4
5.2
2.1
Pack Materials-Page 1
W
Pin1
(mm) Quadrant
8.0
Q3
4.0
8.0
Q3
8.0
12.0
Q1
PACKAGE MATERIALS INFORMATION
www.ti.com
26-Jan-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
OPA690IDBVR
SOT-23
DBV
6
3000
210.0
185.0
35.0
OPA690IDBVT
SOT-23
DBV
6
250
210.0
185.0
35.0
OPA690IDR
SOIC
D
8
2500
367.0
367.0
35.0
Pack Materials-Page 2
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