BB OPA301

OPA300
OPA301
SBOS271A − MAY 2003 − REVISED DECEMBER 2003
Low-Noise, High-Speed, 16-Bit Accurate, CMOS
OPERATIONAL AMPLIFIER
FEATURES
D
D
D
D
D
D
D
D
D
D
DESCRIPTION
High Bandwidth: 150MHz
16-Bit Settling in 150ns
Low Noise: 3nV/√Hz
Low Distortion: 0.003%
Low Power: 9.5mA (typ) on 5.5V
Shutdown to 5µA
Unity Gain Stable
Excellent Output Swing:
(V+) − 100mV to (V−) + 100mV
Single Supply: +2.7V to +5.5V
Tiny Packages: SO-8 and SOT23
The OPA300 and OPA301 high-speed, voltage-feedback, CMOS operational amplifiers are designed for
16-bit resolution systems. The OPA300 and OPA301
are unity-gain stable and feature excellent settling and
harmonic distortion specifications. Low power applications benefit from low quiescent current. The OPA300
features digital shutdown (Enable) function to provide
additional power savings during idle periods. Optimized
for single-supply operation, the OPA300 and OPA301
offer superior output swing and excellent commonmode range.
The OPA300 and OPA301 have 150MHz of unity-gain
bandwidth, low 3nV/√Hz voltage noise, and 0.1%
settling within 30ns. Single-supply operation from 2.7V
(±1.35V) to 5.5V (±2.75V) and an available shutdown
function that reduces supply current to 5µA are useful
for portable low-power applications. The OPA300 and
OPA301 are available in SO-8 and SOT-23 packages,
and are specified over the industrial temperature range
of −40°C to +125°C.
APPLICATIONS
D
D
D
D
16-Bit ADC Input Drivers
Low-Noise Preamplifiers
IF/RF Amplifiers
Active Filtering
OPA300
OPA301
OPA300
NC
1
8
Enable
NC
1
8
NC
−In
2
7
V+
−In
2
7
V+
+In
3
6
VO U T
+In
3
6
V−
4
5
NC
V−
4
5
SO−8
SO−8
NC = Not Connected
NC = Not Connected
OPA301
Out
1
6
V+
VO UT
V−
2
5
NC
+In
3
4
SOT23−6
Out
1
Enable
V−
2
−In
+In
3
5
V+
4
−In
SOT23−5
16-Bit
ADC
OPA300
VIN
Typical Application of the OPA300
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.
Copyright  2003, Texas Instruments Incorporated
! ! www.ti.com
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SBOS271A − MAY 2003 − REVISED DECEMBER 2003
PACKAGE/ORDERING INFORMATION
PRODUCT
PACKAGE-LEAD
PACKAGE
DESIGNATOR(1)
SPECIFIED
TEMPERATURE
RANGE
PACKAGE
MARKING
OPA300D
SO-8
D
−40°C to +125°C
300A
OPA300DBV
SOT23-6
DBV
−40°C to +125°C
A52
OPA301D
SO-8
D
−40°C to +125°C
301A
OPA301DBV
SOT23-5
DBV
−40°C to +125°C
ORDERING
NUMBER
AUP
TRANSPORT
MEDIA, QUANTITY
OPA300AID
Tube, 100
OPA300AIDR
Tape and Reel, 2500
OPA300AIDBVT
Tape and Reel, 250
OPA300AIDBVR
Tape and Reel, 2500
OPA301AID
Tube, 100
OPA301AIDR
Tape and Reel, 2500
OPA301AIDBVT
Tape and Reel, 250
OPA301AIDBVR
Tape and Reel, 2500
(1) For the most current specification and package information, refer to our web site at www.ti.com.
ELECTROSTATIC DISCHARGE SENSITIVITY
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range unless otherwise noted(1)
Power Supply V+ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5V
Signal Input Terminals(2), Voltage . . . . . . . . . . . 0.5V to (V+) + 0.5V
Current . . . . . . . . . . . . . . . . . . . . . ±10mA
Open Short-Circuit Current(3) . . . . . . . . . . . . . . . . . . . . Continuous
Operating Temperature Range . . . . . . . . . . . . . . . −55°C to +125°C
Storage Temperature Range . . . . . . . . . . . . . . . . . −60°C to +150°C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +150°C
Lead Temperature (soldering, 10s) . . . . . . . . . . . . . . . . . . . . . +300°C
(1) 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 implied.
(2) Input terminals are diode clamped to the power-supply rails. Input
signals that can swing more than 0.5V beyond the supply rails
should be current limited to 10mA or less.
(3) Short-circuit to ground; one amplifier per package.
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.
PIN ASSIGNMENTS
OPA300
Top View
SO
1
8
Enable
−In
2
7
V+
+In
3
6
V O UT
V−
4
5
NC
SOT23
OPA300
Out
1
V−
2
+In
3
A52
NC
Top View
SO−8
6
V+
5
Enable
4
−In
SOT23−6(1)
NC = Not Connected
OPA301
OPA301
NC
1
8
NC
−In
2
7
V+
+In
3
6
VO UT
V−
4
5
NC
SO−8
NC = Not Connected
2
Out
1
V−
2
+In
3
5
V+
4
−In
SOT23−5
(1)SOT23-6 pin 1 oriented as shown with reference to package marking.
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SBOS271A − MAY 2003 − REVISED DECEMBER 2003
ELECTRICAL CHARACTERISTICS: VS = 2.7V to 5.5V
Boldface limits apply over the temperature range, TA = −40°C to +125°C.
All specifications at TA = +25°C, RL = 2kΩ connected to VS/2, VOUT = VS/2, and VCM = VS/2, unless otherwise noted.
OPA300, OPA301
PARAMETER
OFFSET VOLTAGE
Input Offset Voltage
Over Temperature
Drift
vs. Power Supply
INPUT VOLTAGE RANGE
Common-Mode Voltage Range
Common-Mode Rejection Ratio
INPUT BIAS CURRENT
Input Bias Current
Input Offset Current
TEST CONDITIONS
TYP
MAX
UNITS
VS = 5V
1
5
7
PSRR
VS = 2.7V to 5.5V, VCM < (V+) –0.9V
2.5
50
mV
mV
µV/°C
µV/V
VCM
CMRR
(V−) − 0.2V < VCM < (V+) – 0.9V
VOS
MIN
dVOS/dT
(V−) − 0.2
66
INPUT IMPEDANCE
Differential
Common-Mode
NOISE
Input Voltage Noise, f = 0.1Hz to 1MHz
Input Voltage Noise Density, f > 1MHz
Input Current Noise Density, f < 1kHz
Differential Gain Error
Differential Phase Error
OPEN-LOOP GAIN
Open−Loop Voltage Gain
Over Temperature
en
in
NTSC, RL = 150Ω
NTSC, RL = 150Ω
AOL
Over Temperature
VS = 5V, RL = 2kΩ, 0.1V < VO < 4.9V
VS = 5V, RL = 2kΩ, 0.1V < VO < 4.9V
VS = 5V, RL = 100Ω, 0.5V < VO < 4.5V
VS = 5V, RL = 100Ω, 0.5V < VO < 4.5V
95
90
95
90
(V+) − 0.9
V
dB
±5
±5
pA
pA
80
±0.1
±0.5
IB
IOS
200
1013 || 3
1013 || 6
Ω || pF
Ω || pF
40
3
1.5
0.01
0.1
µVpp
nV/√Hz
fA/√Hz
%
°
106
dB
dB
dB
dB
106
OUTPUT
Voltage Output Swing from Rail
Short-Circuit Current
Capacitive Load Drive
FREQUENCY RESPONSE
Gain-Bandwidth Product
Slew Rate
Settling Time, 0.01%
0.1%
Overload Recovery Time
Total Harmonic Distortion + Noise
POWER SUPPLY
Specified Voltage Range
Operating Voltage Range
Quiescent Current (per amplifier)
Over Temperature
RL = 2kΩ, AOL > 95dB
RL = 100Ω, AOL > 95dB
ISC
CLOAD
GBW
SR
tS
THD+N
SHUTDOWN
tOFF
tON
VL (shutdown)
VH (amplifier is active)
IQSD
TEMPERATURE RANGE
Specified Range
Operating Range
Storage Range
Thermal Resistance
SO-8
SOT23-5
SOT23-6
150
80
90
30
30
0.003
G = +1
VS = 5V, 2V Step, G = +1
Gain = −1
VS = 5V, VO = 3Vpp, G = +1, f = 1kHz
VS
IQ
75
100
300
500
70
See Typical Characteristics
2.7
IO = 0
MHz
V/µs
ns
ns
ns
%
5.5
2.7 to 5.5
9.5
12
13
V
V
mA
mA
(V−) + 0.8
(V+) + 0.2
10
ns
µs
V
V
µA
40
5
(V−) − 0.2
(V−) + 2.5
3
−40
−55
−65
125
150
150
θJA
200
200
200
mV
mV
mA
°C
°C
°C
°C/W
°C/W
°C/W
°C/W
3
"##
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SBOS271A − MAY 2003 − REVISED DECEMBER 2003
TYPICAL CHARACTERISTICS
All specifications at TA = 25°C, V+ = 5V, and RL = 150Ω connected to VS/2 unless otherwise noted.
NONINVERTING GAIN
SMALL−SIGNAL FREQUENCY RESPONSE
INVERTING GAIN
SMALL−SIGNAL FREQUENCY RESPONSE
3
3
VO = 0.1VPPV
RF = 310Ωfor G > 1
G=1
Normalized Gain (dB)
Normalized Gain (dB)
0
−3
G=5
G=2
−9
G = 10
1M
G = −10
−9
−15
10M
100M
1G
1M
10M
Frequency (Hz)
1G
SMALL−SIGNAL STEP RESPONSE
Output Voltage (10mV/div)
Output Voltage (500mV/div)
VOUT
Time (50ns/div)
Time (5ns/div)
LARGE−SIGNAL ENABLE/DISABLE RESPONSE
Enable Pin
Normalized Gain (dB)
Output Voltage (500mV/div)
100M
Frequency (Hz)
LARGE−SIGNAL STEP RESPONSE
Amplifier
Output
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
−0.1
−0.2
−0.3
Time (100µs/div)
4
G = −2
G = −5
−6
−12
VO = 0.1VPP
RF = 310Ωfor G > 1
−15
G = −1
−3
0.1dB GAIN FLATNESS FOR VARIOUS RF
Gain = 2
VO = 0.1VPP
RF = 825Ω
RF = 450Ω
RF = 205Ω
1M
10M
Frequency (MHz)
100M
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SBOS271A − MAY 2003 − REVISED DECEMBER 2003
TYPICAL CHARACTERISTICS (continued)
All specifications at TA = 25°C, V+ = 5V, and RL = 150Ω connected to VS/2 unless otherwise noted.
HARMONIC DISTORTION vs OUTPUT VOLTAGE
RL = 200Ω
f = 1MHz
RF = 310Ω
G=2
−60
HARMONIC DISTORTION vs NONINVERTING GAIN
−50
Harmonic Distortion (dBc)
Harmonic Distortion (dBc)
−50
THD
−70
2nd−Harmonic
−80
3rd−Harmonic
−90
−100
VO = 2VPP
RL = 200Ω
f = 1MHz
RF = 310Ω
−60
−70
THD
2nd−Harmonic
−80
3rd−Harmonic
−90
−100
−110
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
1
10
Gain (V/V)
Output Voltage (VPP)
HARMONIC DISTORTION vs INVERTING GAIN
−70
THD
2nd−Harmonic
3rd−Harmonic
−80
−90
−100
−60
−70
VO = 2VPP
RL = 200Ω
Gain = 2
RF = 310Ω
THD
−80
2nd−Harmonic
−90
3rd−Harmonic
−100
−110
−110
1
10
−60
−120
100k
1M
10M
Gain (V/V)
Frequency (Hz)
HARMONIC DISTORTION vs LOAD RESISTANCE
INPUT VOLTAGE AND CURRENT NOISE
SPECTRAL DENSITY vs FREQUENCY
10k
THD
−70
2nd−Harmonic
−75
VO = 2VPP
f = 1MHz
Gain = 2
RF = 310Ω
Voltage Noise (nV/√Hz)
Current Noise (fA/√Hz)
−65
−80
−85
−90
HARMONIC DISTORTION vs FREQUENCY
−50
Harmonic Distortion (dBc)
VO = 2VPP
RL = 200Ω
f = 1MHz
RF = 310Ω
−60
Harmonic Distortion (dBc)
Harmonic Distortion (dBc)
−50
3rd−Harmonic
Current Noise
1k
Voltage Noise
100
10
−95
−100
100
1k
Load Resistance (Ω)
1
10
100
1k
10k
100k
1M
10M
Frequency (Hz)
5
"##
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SBOS271A − MAY 2003 − REVISED DECEMBER 2003
TYPICAL CHARACTERISTICS (continued)
All specifications at TA = 25°C, V+ = 5V, and RL = 150Ω connected to VS/2 unless otherwise noted.
FREQUENCY RESPONSE FOR VARIOUS RL
9
Gain = 1
VO = 0.1VPP
FREQUENCY RESPONSE FOR VARIOUS CL
15
Gain = 1
RLOAD = 1kΩ
9
3
CLOAD = 47pF
CLOAD = 100pF
−3
CLOAD = 4.7pF
Gain (dB)
Gain (dB)
3
RLOAD = 150Ω
−9
−3
−9
RLOAD = 50Ω
−15
CL
−15
−21
10M
100M
1G
−21
10M
100M
Frequency (Hz)
COMMON−MODE REJECTION RATIO AND
POWER−SUPPLY REJECTION RATIO vs FREQUENCY
FREQUENCY RESPONSE vs CAPACITIVE LOAD
100
CLOAD = 1pF
RS = 75Ω
CLOAD = 47pF
RS = 30Ω
RS
−21
CL
60
50
40
30
20
C LOAD = 100pF
RS = 20Ω
−27
10M
CMRR
70
CLOAD = 10pF
RS = 40Ω
−15
PSRR V−
80
CLOAD = 5pF
RS = 55Ω
−9
PSRR V+
90
PSRR (dB)
CMRR (dB)
Normalized Gain (dB)
3
−3
10
100M
0
1G
10k
100k
1M
Frequency (Hz)
1M
Frequency (Hz)
10M
100M
1G
dP (_)
dG (%)
0.6
dP
−120
0.4
−150
0.2
−180
100k
0.8
Phase (_)
Gain (dB)
−90
10k
dG
0
1
2
3
Number of 150Ω Loads
6
1G
1.0
−30
Phase
−60
1k
100M
COMPOSITE VIDEO
DIFFERENTIAL GAIN AND PHASE
0
Gain
10M
Frequency (Hz)
OPEN−LOOP GAIN AND PHASE vs FREQUENCY
110
100
90
80
70
60
50
40
30
20
10
0
−10
100
1G
Frequency (Hz)
4
"##
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SBOS271A − MAY 2003 − REVISED DECEMBER 2003
TYPICAL CHARACTERISTICS (continued)
All specifications at TA = 25°C, V+ = 5V, and RL = 150Ω connected to VS/2 unless otherwise noted.
OUTPUT VOLTAGE SWING vs OUTPUT CURRENT
OUTPUT VOLTAGE SWING vs OUTPUT CURRENT
2.7
5.0
VS = 5V
2.1
Output Voltage (V)
Output Voltage (V)
4.0
VS = 2.7V
2.4
25_C
−40_ C
3.0
−55_ C
150_ C 125_ C 85_ C
2.0
25_ C
1.8
1.5
150_ C 125_ C 85_C 25_ C −40_C −55_ C
1.2
0.9
0.6
1.0
0.3
0
0
0
10
20
30
40
50
60
70
80
0
10
20
Output Current (mA)
30
40
50
60
70
80
Output Current (mA)
QUIESCENT CURRENT vs TEMPERATURE
INPUT BIAS CURRENT vs TEMPERATURE
1
12
Quiescent Current (mA)
Input Bias Current (pA)
11
0.1
10
9
8
7
6
0.01
−40
−20
0
20
40
60
80
100
120
−40
140
−20
0
20
Temperature (_C)
40
60
80
100
120
140
Temperature (_C)
POWER−SUPPLY REJECTION RATIO AND
COMMON−MODE REJECTION RATIO vs TEMPERATURE
INPUT BIAS CURRENT vs COMMON−MODE VOLTAGE
2
100
90
PSRR
PSRR (dB)
CMRR (dB)
Input Bias Current (pA)
95
1
0
−1
85
80
CMRR
75
70
65
−2
−3
−2
−1
0
1
Common−Mode Voltage (V)
2
3
60
−40
−20
0
20
40
60
80
100
120
140
Temperature (_ C)
7
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SBOS271A − MAY 2003 − REVISED DECEMBER 2003
TYPICAL CHARACTERISTICS (continued)
All specifications at TA = 25°C, V+ = 5V, and RL = 150Ω connected to VS/2 unless otherwise noted.
SHORT−CIRCUIT CURRENT vs TEMPERATURE
QUIESCENT CURRENT vs SUPPLY VOLTAGE
80
9
VS = 5.5V
8
Quiescent Current (mA)
Short−Circuit Current (mA)
60
40
20
0
VS = 3.5V
−20
VS = 5V
VS = 2.7V
−40
7
6
5
4
3
2
−60
1
−80
−40
VS = 5.5V
−20
0
20
40
60
80
100
0
120
0
1
2
Temperature (_C)
3
4
OUTPUT IMPEDANCE vs FREQUENCY
6
MAXIMUM OUTPUT VOLTAGE vs FREQUENCY
5
1000
RLOAD = 2kΩ
VS = 5V
4
100
Output Voltage (VPP)
Output Impedance, ZO (Ω)
5
Supply Voltage (V)
G=2
10
G=1
1
3
VS = 2.7V
2
1
0.1
0
0.01
10k
100k
1M
10M
100M
1
10
Frequency (Hz)
100
Frequency (MHz)
OPEN−LOOP GAIN vs TEMPERATURE
OUTPUT SETTLING TIME TO 0.1%
0.2
120
0.1
0
−0.1
R LOAD = 2kΩ
Output Error (%)
Open−Loop Gain (dB)
110
100
90
RLOAD = 100Ω
80
−0.5
−0.6
−0.7
−1.0
−20
0
20
40
60
80
Temperature (_ C)
8
−0.3
−0.4
−0.8
−0.9
70
60
−40
−0.2
100
120
140
0
20
40
60
Time (ns)
80
100
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SBOS271A − MAY 2003 − REVISED DECEMBER 2003
TYPICAL CHARACTERISTICS (continued)
All specifications at TA = 25°C, V+ = 5V, and RL = 150Ω connected to VS/2 unless otherwise noted.
OFFSET VOLTAGE
PRODUCTION DISTRIBUTION
OFFSET VOLTAGE DRIFT
PRODUCTION DISTRIBUTION
20
20
18
Percent of Amplifiers
Percent of Amplifiers
16
14
12
10
8
6
15
10
5
4
2
0
0
−5
−4
−3
−2
−1
0
1
Offset Voltage (mV)
2
3
4
5
−10
−8
−6
−4
−2
0
2
4
6
8
10
Offset Voltage Drift (µV/_ C)
9
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APPLICATIONS INFORMATION
Built on HPA07, the latest TI high-precision analog
process, the OPA300 single-supply CMOS op amp is
designed to interface with high-speed 16-bit
analog-to-digital converters (ADCs). Featuring wide
150MHz bandwidth, fast 150nS settling time to 16 bits,
and high open loop gain, the OPA300 series offer
excellent performance in a small SO-8 and tiny SOT23
packages.
PCB LAYOUT
As with most high-speed operational amplifiers, board
layout requires special attention to maximize AC and
DC performance. Extensive use of ground planes, short
lead lengths, and high-quality bypass capacitors will
minimize leakage that can compromise signal quality.
Guard rings applied with potential as near to the input
pins as possible help minimize board leakage.
INPUT AND ESD PROTECTION
THEORY OF OPERATION
The OPA30x uses a classic two-stage topology, shown
in Figure 1. The differential input pair is biased to
maximize slew rate without compromising stability or
bandwidth. The folded cascode adds the signal from the
input pair and presents a differential signal to the class
AB output stage. The class AB output stage allows rail
to rail output swing, with high−impedance loads
(> 2kΩ), typically 100mV from the supply rails. With 10Ω
loads, a useful output swing can be achieved and still
maintain high open-loop gain. See the typical
characteristic Output Voltage Swing vs Output Current.
All OPA30x pins are static protected with internal ESD
protection diodes tied to the supplies, as shown in
Figure 2. These diodes will provide overdrive protection
if the current is externally limited to 10mA, as stated in
the Absolute Maximum Ratings. Any input current
beyond the Absolute Maximum Ratings, or long-term
operation at maximum ratings, will shorten the lifespan
of the amplifier.
+V
External
Pin
Internal
Circuitry
+VS
−V
Figure 2. ESD Protection Diodes
VOUT
+
VIN
−
VBIAS
Figure 1. OPA30x Classic Two-Stage Topology
OPERATING VOLTAGE
OPA30x op amp parameters are fully specified from
+2.7V to +5.5V. Supply voltages higher than 5.5V
(absolute maximum) can cause permanent damage to
the amplifier. Many specifications apply from –40°C to
+125°C. Parameters that vary significantly with
operating voltages or temperature are shown in the
Typical Characteristics.
10
ENABLE FUNCTION
The shutdown function of the OPA300 is referenced to
the negative supply voltage of the operational amplifier.
A logic level HIGH enables the op amp. A valid logic
HIGH is defined as 2.5V above the negative supply
applied to the enable pin. A valid logic LOW is defined
as < 0.8V above the negative supply pin. If dual or split
power supplies are used, care should be taken to
ensure logic input signals are properly referred to the
negative supply voltage. If this pin is not connected to
a valid high to low voltage, the internal circuitry will pull
the node high and enable the part to function.
The logic input is a high-impedance CMOS input. For
battery-operated applications, this feature may be used
to greatly reduce the average current and extend
battery life. The enable time is 10µs; disable time is 1µs.
When disabled, the output assumes a high-impedance
state. This allows the OPA300 to be operated as a gated
amplifier, or to have its output multiplexed onto a
common analog output bus.
"##
"#$
www.ti.com
SBOS271A − MAY 2003 − REVISED DECEMBER 2003
DRIVING CAPACITIVE LOADS
DRIVING A 16-BIT ADC
When using high−speed operational amplifiers, it is
extremely important to consider the effects of
capacitive loading on amplifier stability. Capacitive
loading will interact with the output impedance of the
operational amplifier, and depending on the capacitor
value, may significantly decrease the gain bandwidth,
as well as introduce peaking. To reduce the effects of
capacitive loading and allow for additional capacitive
load drive, place a series resistor between the output
and the load. This will reduce available bandwidth, but
permit stable operation with capacitive loading.
Figure 3 illustrates the recommended relationship
between the resistor and capacitor values.
The OPA30x features excellent THD+noise, even at
frequencies greater than 1MHz, with a 16-bit settling
time of 150ns. Figure 4 shows a total single supply
solution for high-speed data acquisition. The OPA30x
directly drives the ADS8401, a 1.25 mega sample per
second (MSPS) 16-bit data converter. The OPA30x is
configured in an inverting gain of 1, with a 5V single
supply. Results of the OPA30x performance are
summarized in Table 1.
130pF
(mica)
1820Ω
fS = 1.25MSPS
f = 10kHz
100
5V
Series Resistance (Ω)
1820Ω
VIN
75
10Ω
130pF
(mica)
ADS8401
OPA30x
1.5nF
50
25
Figure 4. The OPA30x Drives the 16-Bit ADS8401
0
1
10
100
Capacitive Load (pF)
Figure 3. Recommended RS and CL Combinations
Amplifiers configured in unity gain are most susceptible
to stability issues. The typical characteristic, Frequency
Response vs Capacitive Load, describes the relationship between capacitive load and stability for the
OPA30x. In unity gain, the OPA300 is capable of driving
a few picofarads of capacitive load without compromising stability. Board level parasitic capacitance can often
fall into the range of a picofarad or more, and should be
minimized through good circuit-board layout practices
to avoid compromising the stability of the OPA30x. For
more information on detecting parasitics during testing,
see the Application Note Measuring Board Parasitics in
High-Speed Analog Design (SBOA094), available at
the TI web site www.ti.com.
PARAMETER
RESULTS (f = 10kHz)
THD
−99.3dB
SFDR
101.2dB
THD+N
84.2dB
SNR
84.3dB
Table 1. OPA30x Performance Results Driving a
1.25MSPS ADS8401
11
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