Burr-Brown OPA552FA/500 High-voltage, high-current operational amplifier Datasheet

OPA551
OPA552
®
OPA
551
OPA
551
OPA
551
For most current data sheet and other product
information, visit www.burr-brown.com
High-Voltage, High-Current
OPERATIONAL AMPLIFIERS
FEATURES
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DESCRIPTION
WIDE SUPPLY RANGE: ±4V to ±30V
HIGH OUTPUT CURRENT: 200mA Continuous
LOW NOISE: 14nV/√Hz
FULLY PROTECTED:
Thermal Shutdown
Output Current-Limited
THERMAL SHUTDOWN INDICATOR
WIDE OUTPUT SWING: 2V From Rail
FAST SLEW RATE:
OPA551: 15V/µs
OPA552: 24V/µs
WIDE BANDWIDTH:
OPA551: 3MHz
OPA552: 12MHz
PACKAGES: DIP-8, SO-8, or DDPAK-7
The OPA551 and OPA552 are low cost op amps with
high-voltage (60V) and high-current (200mA) capability.
The OPA551 is unity-gain stable and features high
slew rate (15Vµs) and wide bandwidth (3MHz). The
OPA552 is optimized for gains of 5 or greater, and
offers higher speed with a slew rate of 24V/µs and a
bandwidth of 12MHz. Both are suitable for telephony,
audio, servo, and test applications.
These laser-trimmed, monolithic integrated circuits
provide excellent low-level accuracy along with high
output swing. High performance is maintained as the
amplifier swings to its specified limits.
The OPA551 and OPA552 are internally protected
against over-temperature conditions and current overloads. The thermal shutdown indicator “flag” provides
a current output to alert the user when thermal shutdown has occurred.
The OPA551 and OPA552 are available in DIP-8 and
SO-8 packages, as well as a DDPAK-7 surfacemount plastic power package. They are specified for
operation over the extended industrial temperature
range, –40°C to +125°C.
APPLICATIONS
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TELEPHONY
TEST EQUIPMENT
AUDIO AMPLIFIER
TRANSDUCER EXCITATION
SERVO DRIVER
OPA551, OPA552
OPA551, OPA552
OPA551, OPA552
1 2 3 4 5 6 7
NOTE: Tab is
connected to
V– supply.
+In NC V+ Flag
–In V– Out
V–
1
8
Flag
–In
2
7
V+
+In
3
6
Out
V–
4
5
V–
NC
1
8
Flag
–In
2
7
V+
+In
3
6
Out
V–
4
5
NC
DIP-8 (P)
SO-8 (U)
DDPAK-7 Surface-Mount (F)
International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111
Twx: 910-952-1111 • Internet: http://www.burr-brown.com/ • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
®
©1999 Burr-Brown Corporation
PDS-1472A
1
Printed in U.S.A. July, 1999
OPA551, OPA552
SPECIFICATIONS: VS = ±30V
OPA551
At TJ = +25°C(1), RL = 3kΩ connected to ground and VOUT = 0V, unless otherwise noted.
Boldface limits apply over the specified junction temperature range, TJ = –40°C to +125°C.
OPA551UA, PA, FA
PARAMETER
CONDITION
OFFSET VOLTAGE
Input Offset Voltage
TJ = –40°C to +125°C
vs Temperature
vs Power Supply
VOS
MIN
TYP
±1
UNITS
±3
10
30
mV
mV
µV/°C
µV/V
IB
IOS
±20
±3
±100
±100
pA
pA
en
in
14
3.5
dVOS /dT
PSRR
VCM = 0V, IO = 0
MAX
±7
VS = ±4V to ±30V, VCM = 0V
±5
INPUT BIAS CURRENT
Input Bias Current
Input Offset Current
NOISE
Input Voltage Noise Density, f = 1kHz
Current Noise Density, f = 1kHz
INPUT VOLTAGE RANGE
Common-Mode Voltage Range
Common-Mode Rejection Ratio
VCM
CMRR
–27.5V < VCM < +27.5V
(V–) + 2.5
92
INPUT IMPEDANCE
Differential
Common-Mode
OPEN-LOOP GAIN
Open-Loop Voltage Gain
TJ = –40°C to +125°C
FREQUENCY RESPONSE
Gain-Bandwidth Product
Slew Rate
Settling Time: 0.1%
0.01%
Total Harmonic Distortion + Noise, f = 1kHz
AOL
GBW
SR
THD+N
Overload Recovery Time
OUTPUT
Voltage Output
TJ = –40°C to +125°C
VOUT
TJ = –40°C to +125°C
Maximum Continuous Current Output: dc
IO
Short-Circuit Current
ISC
Capacitive Load Drive
CLOAD
SHUTDOWN FLAG
Thermal Shutdown Status Output
Normal Operation
Thermally Shutdown
Voltage Compliance Range
Junction Temperature
Shutdown
Reset from Shutdown
POWER SUPPLY
Specified Voltage
Operating Voltage Range
Quiescent Current
TJ = –40°C to +125°C
TEMPERATURE RANGE
Specified Range
Operating Range
Storage Range
Thermal Resistance
SO-8 Surface Mount
DIP-8
DDPak-7
DDPak-7
RL = 3kΩ, –28V < VO < +28V
RL = 3kΩ, –28V < VO < +28V
RL = 300Ω, –27V < VO < +27V
110
100
G=1
G = 1, CL = 100pF, 10V Step
G = 1, CL = 100pF, 10V Step
VO = 15Vrms, RL = 3kΩ, G = 3
VO = 15Vrms, RL = 300Ω, G = 3
VIN • Gain = VS
IO = 200mA
IO = 200mA
IO = 10mA
IO = 10mA
Package Dependent—See Text
(V–) + 3.0
(V–) + 3.5
(V–) + 2.0
(V–) + 2.5
±200
Stable Operation
Sourcing
Sourcing
80
V–
nV/√Hz
fA/√Hz
102
(V+) – 2.5
V
dB
1013 || 2
1013 || 6
Ω || pF
Ω || pF
126
120
dB
dB
dB
3
±15
1.3
2
0.0005
0.0005
1
MHz
V/µs
µs
µs
%
%
µs
(V+)
(V+)
(V+)
(V+)
–
–
–
–
3.0
3.5
2.0
2.7
V
V
V
V
mA
mA
1
160
(V+) – 1.5
µA
µA
V
±380
See Typical Curve
0.05
120
°C
°C
160
140
VS
IQ
±4
IO = 0
TJ
TJ
TA
±30
±7
–40
–55
–65
θJA
θJA
θJA
θJC
±30
±8.5
±10
V
V
mA
mA
+125
+125
+150
°C
°C
°C
90
100
65
3
NOTES: (1) All tests are high-speed tested at +25°C ambient temperature. Effective junction temperature is +25°C unless otherwise noted.
®
OPA551, OPA552
2
°C/W
°C/W
°C/W
°C/W
SPECIFICATIONS: VS = ±30V
OPA552
At TJ = +25°C(1), RL = 3kΩ connected to Ground and VOUT = 0V, unless otherwise noted.
Boldface limits apply over the specified junciton temperature range, TJ = –40°C to +125°C.
OPA552UA, PA, FA
PARAMETER
OFFSET VOLTAGE
Input Offset Voltage
TJ = –40°C to +125°C
vs Temperature
vs Power Supply
CONDITION
VOS
MIN
TYP
±1
UNITS
±3
10
30
mV
mV
µV/°C
µV/V
IB
IOS
±20
±3
±100
±100
pA
pA
en
in
14
3.5
dVOS /dT
PSRR
VCM = 0V, IO = 0
MAX
±7
VS = ±4V to ±30V, VCM = 0V
±5
INPUT BIAS CURRENT
Input Bias Current
Input Offset Current
NOISE
Input Voltage Noise Density, f = 1kHz
Current Noise Density, f = 1kHz
INPUT VOLTAGE RANGE
Common-Mode Voltage Range
Common-Mode Rejection Ratio
VCM
CMRR
102
V
dB
1013 || 2
1013 || 6
Ω || pF
Ω || pF
126
120
dB
dB
dB
G=5
G = 5, CL = 100pF, 10V Step
G = 5, CL = 100pF, 10V Step
VO = 15Vrms, RL = 3kΩ, G = 5
VO = 15Vrms, RL = 300Ω, G = 5
12
±24
2.2
3
0.0005
0.0005
MHz
V/µs
µs
µs
%
%
VIN • Gain = VS
1
µs
–27.5V < VCM < +27.5V
(V–) + 2.5
92
INPUT IMPEDANCE
Differential
Common-Mode
OPEN-LOOP GAIN
Open-Loop Voltage Gain
TJ = –40°C to +125°C
FREQUENCY RESPONSE
Gain-Bandwidth Product
Slew Rate
Settling Time: 0.1%
0.01%
Total Harmonic Distortion + Noise, f = 1kHz
AOL
GBW
SR
THD+N
Overload Recovery Time
OUTPUT
Voltage Output
TJ = –40°C to +125°C
VOUT
TJ = –40°C to +125°C
Maximum Continuous Current Output: dc
IO
Short-Circuit Current
ISC
Capacitive Load Drive
CLOAD
SHUTDOWN FLAG
Thermal Shutdown Status Output
Normal Operation
Thermally Shutdown
Voltage Compliance Range
Junction Temperature
Shutdown
Reset from Shutdown
POWER SUPPLY
Specified Voltage
Operating Voltage Range
Quiescent Current
TJ = –40°C to +125°C
TEMPERATURE RANGE
Specified Range
Operating Range
Storage Range
Thermal Resistance
SO-8 Surface Mount
DIP-8
DDPak-7
DDPak-7
nV/√Hz
fA/√Hz
RL = 3kΩ, –28V < VO < +28V
RL = 3kΩ, –28V < VO < +28V
RL = 300Ω, –27V < VO < +27V
IO = 200mA
IO = 200mA
IO = 10mA
IO = 10mA
Package Dependent—See Text
110
100
(V–) + 3.0
(V–) + 3.5
(V–) + 2.0
(V–) + 2.5
±200
Stable Operation
Sourcing
Sourcing
80
V–
(V+) – 2.5
(V+)
(V+)
(V+)
(V+)
–
–
–
–
3.0
3.5
2.0
2.7
V
V
V
V
mA
mA
1
160
(V+) – 1.5
µA
µA
V
±380
See Typical Curve
0.05
120
°C
°C
160
140
VS
IQ
±4
IO = 0
TJ
TJ
TA
±30
±7
–40
–55
–65
θJA
θJA
θJA
θJC
±30
±8.5
±10
V
V
mA
mA
+125
+125
+150
°C
°C
°C
90
100
65
3
°C/W
°C/W
°C/W
°C/W
NOTES: (1) All tests are high-speed tested at +25°C ambient temperature. Effective junction temperature is +25°C unless otherwise noted.
®
3
OPA551, OPA552
ELECTROSTATIC
DISCHARGE SENSITIVITY
ABSOLUTE MAXIMUM RATINGS(1)
Output Current ................................................................. See SOA Curve
Supply Voltage, V+ to V– ................................................................... 60V
Input Voltage Range ....................................... (V–) – 0.5V to (V+) + 0.5V
Operating Temperature .................................................. –55°C to +125°C
Storage Temperature ..................................................... –65°C to +150°C
Junction Temperature .................................................................... +150°C
Lead Temperature (soldering 10s, DIP-8) ...................................... 300°C
(soldering 3s, SO-8 and DDPAK) .................... 240°C
ESD Capability (Human Body Model) ............................................. 3000V
This integrated circuit can be damaged by ESD. Burr-Brown
recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.
ESD damage can range from subtle performance 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.
NOTE: (1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods may degrade
device reliability.
PACKAGE /ORDERING INFORMATION
PRODUCT
PACKAGE
PACKAGE
DRAWING
NUMBER(1)
SPECIFIED
TEMPERATURE
RANGE
PACKAGE
MARKING
ORDERING
NUMBER(2)
TRANSPORT
MEDIA
OPA551UA
SO-8
182
–40°C to +125°C
OPA551UA
"
"
"
"
"
OPA551UA
OPA551UA/2K5
OPA551PA
OPA551FA
OPA551FA/500
OPA552UA
OPA552UA/2K5
OPA552PA
OPA552FA
OPA552FA/500
Rails
Tape and Reel
Rails
Rails
Tape and Reel
Rails
Tape and Reel
Rails
Rails
Tape and Reel
OPA551PA
OPA551FA
DIP-8
DDPAK-7
006
328
–40°C to +125°C
–40°C to +125°C
OPA551PA
OPA551FA
"
"
"
"
"
OPA552UA
"
OPA552PA
OPA552FA
SO-8
182
–40°C to +125°C
OPA552UA
"
"
"
"
DIP-8
DDPAK-7
006
328
–40°C to +125°C
–40°C to +125°C
OPA552PA
OPA552FA
"
"
"
"
"
NOTES: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book. (2) Products followed by a slash
(/) are only available in Tape and Reel in the quantities indicated (e.g., /2K5 indicates 2500 devices per reel). Ordering 2500 pieces of “OPA551UA/2K5” will get
a single 2500-piece Tape and Reel. For detailed Tape and Reel mechanical information, refer to Appendix B of Burr-Brown IC Data Book.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility
for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change without notice. No patent rights or
licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support
devices and/or systems.
®
OPA551, OPA552
4
TYPICAL PERFORMANCE CURVES
At TJ = +25°C, VS = ±30V and RL = 3kΩ, unless otherwise noted.
All temperatures are junction temperatures unless otherwise noted. Refer to the Applications Information section to calculate junction temperatures from ambient
temperatures for a specific configuration.
OPEN-LOOP GAIN AND PHASE vs FREQUENCY
OPA552
OPEN-LOOP GAIN AND PHASE vs FREQUENCY
OPA551
140
140
0
Gain (dB)
80
120
–40
100
–40
–60
80
–60
Phase
60
–80
40
–100
–20
Gain
60
–80
Phase
40
–100
20
–120
20
–120
0
–140
0
–140
–160
–20
–160
–180
10M
–40
–20
–40
1
10
100
1k
10k
100k
1M
1
10
100
1k
10k
100k
–180
10M
1M
Frequency (Hz)
Frequency (Hz)
POWER SUPPLY REJECTION RATIO vs FREQUENCY
COMMON-MODE REJECTION RATIO vs FREQUENCY
120
120
100
100
80
80
PSRR (dB)
CMRR (dB)
–PSRR
60
+PSRR
40
40
20
20
0
0
1
10
100
1k
10k
100k
1M
1
10M
10
100
1k
10k
100k
1M
Frequency (Hz)
Frequency (Hz)
INPUT VOLTAGE AND CURRENT NOISE
SPECTRAL DENSITY vs FREQUENCY
TOTAL HARMONIC DISTORTION + NOISE
vs FREQUENCY
10k
10M
0.1
VO = 15Vrms
RL = 3kΩ, 300Ω
G = 3 (OPA551)
G = 5 (OPA552)
1k
THD+N (%)
Voltage Noise (nV/√Hz)
Current Noise (fA/√Hz)
60
in
100
10
0.01
0.001
en
1
0.0001
10
100
1k
10k
100k
1M
1
Frequency (Hz)
100
1k
10k
100k
Frequency (Hz)
®
5
OPA551, OPA552
Phase (°)
100
–20
Gain (dB)
Gain
Phase (°)
120
0
OPA552
OPA551
TYPICAL PERFORMANCE CURVES
(Cont.)
At TJ = +25°C, VS = ±30V and RL = 3kΩ, unless otherwise noted.
All temperatures are junction temperatures unless otherwise noted. Refer to the Applications Information section to calculate junction temperatures from ambient
temperatures for a specific configuration.
OUTPUT VOLTAGE SWING vs OUTPUT CURRENT
±30
(V+)
±25
(V+)–1
Output Voltage Swing (V)
Maximum Output Voltage (V)
MAXIMUM OUTPUT VOLTAGE SWING
vs FREQUENCY
±20
OPA552
±15
OPA551
±10
±5
Without Slew-Induced
Distortion
+85°C
+25°C
(V+)–2
–55°C
(V+)–3
(V–)+3
+25°C
–55°C
(V–)+2
(V–)+1
0
+85°C
(V–)
1
10
100
1k
10k
100k
1M
10M
0
50
100
150
200
250
300
350
400
Frequency (Hz)
Output Current (mA)
OPEN-LOOP GAIN, POWER SUPPLY REJECTION RATIO,
AND COMMON-MODE REJECTION RATIO
vs TEMPERATURE
INPUT BIAS CURRENT AND INPUT OFFSET CURRENT
vs TEMPERATURE
100k
130
125
AOL
10k
120
Current (pA)
110
PSRR
105
100
CMRR
1k
+IB
100
95
–IB
10
90
85
–IOS
80
–75
–25
25
75
1
–75
125
QUIESCENT CURRENT AND SHORT-CIRCUIT CURRENT
vs TEMPERATURE
8
430
IQ
410
370
+ISC
4
350
3
330
2
310
1
290
0
–75
ISC (mA)
390
–ISC
5
–25
0
25
50
75
100
125
150
50
75
100
125
OPA552
OPA551
0
20
40
60
Temperature (°C)
Temperature (°C)
®
OPA551, OPA552
25
10
1
–80 –60 –40 –20
270
–50
0
100
Gain Bandwidth Product (MHz)
450
6
–25
GAIN BANDWIDTH PRODUCT vs TEMPERATURE
9
7
–50
Ambient Temperature (°C)
Ambient Temperature (°C)
IQ (mA)
Gain (dB)
115
6
80
100 120 140
TYPICAL PERFORMANCE CURVES
(Cont.)
At TJ = +25°C, VS = ±30V and RL = 3kΩ, unless otherwise noted.
All temperatures are junction temperatures unless otherwise noted. Refer to the Applications Information section to calculate junction temperatures from ambient
temperatures for a specific configuration.
INPUT BIAS CURRENT AND INPUT OFFSET CURRENT
vs COMMON-MODE VOLTAGE
35
30
30
25
25
Current (pA)
20
OPA551
15
10
5
5
0
40
60
80
100 120
–5
–30
140
–20
–10
0
10
20
Junction Temperature (°C)
Common-Mode Voltage (V)
QUIESCENT CURRENT AND SHORT-CIRCUIT CURRENT
vs SUPPLY VOLTAGE
OFFSET VOLTAGE
PRODUCTION DISTRIBUTION
18
405
–ISC
395
IQ
6.8
385
+ISC
375
6.0
Supply Voltage (V)
< 1.8
35
< 1.2
30
< 0.6
25
< 0.0
20
< –0.6
15
< –1.2
10
3
< –3.0
5
6
0
365
0
9
< –1.8
6.4
12
< –2.4
7.2
Typical production
distribution of
packaged units.
15
Percent of Amplifiers (%)
7.6
30
< 3.0
20
IOS
< 2.4
0
–IB
15
10
0
–60 –40 –20
Quiescent Current (mA)
+IB
20
OPA552
Short-Circuit Current (mA)
Slew Rate (V/µs)
SLEW RATE vs TEMPERATURE
Offset Voltage (mV)
OFFSET VOLTAGE DRIFT
PRODUCTION DISTRIBUTION
SETTLING TIME vs CLOSED-LOOP GAIN
18
Typical production
distribution of
packaged units.
16
OPA551
0.01%
Settling Time (µs)
14
12
10
8
6
OPA551
0.1%
10
OPA552
0.01%
OPA552
0.1%
4
2
0
1
< 15.0
< 13.5
< 12.0
< 10.5
< 9.0
< 7.5
< 6.0
< 4.50
< 3.0
< 1.5
1
< 0.0
Percent of Amplifiers (%)
100
10
100
Gain (V/V)
Offset Drift µV/°C
®
7
OPA551, OPA552
TYPICAL PERFORMANCE CURVES
(Cont.)
At TJ = +25°C, VS = ±30V and RL = 3Ω, unless otherwise noted.
All temperatures are junction temperatures unless otherwise noted. Refer to the Applications Information section to calculate junction temperatures from ambient
temperatures for a specific configuration.
LARGE-SIGNAL STEP RESPONSE
OPA551, G = 1, CL = 100pF
SMALL-SIGNAL OVERSHOOT vs LOAD CAPACITANCE
60
50
OPA551
OPA551
G = –1
40
5V/div
OPA552
G = –6
30
20
OPA551
G = –2
10
OPA552, G = –8
0
0.01
0.1
1
10
Time (1µs/div)
Load Capacitance (nF)
LARGE-SIGNAL STEP RESPONSE
OPA552, G = 5, CL = 100pF
SMALL-SIGNAL STEP RESPONSE
OPA551, G = 1, CL = 100pF
OPA551
5V/div
25mV/div
OPA552
Time (1µs/div)
Time (1µs/div)
SMALL-SIGNAL STEP RESPONSE
OPA552, G = 5, CL = 100pF
SMALL-SIGNAL STEP RESPONSE
OPA551, G = –1, CL = 1000pF
OPA552
OPA551
5V/div
100mV/div
Overshoot (%)
OPA551, G = 1
OPA552
G = –4
Time (1µs/div)
Time (1µs/div)
®
OPA551, OPA552
8
APPLICATIONS INFORMATION
CURRENT LIMIT
The OPA551 and OPA552 are designed with internal current-limiting circuitry that limits the output current to approximately 380mA. The current limit varies with increasing
junction temperature as shown in the typical curve “Current
Limit vs Temperature.” This, in combination with the thermal protection circuitry, provides protection from many
types of overload conditions including short circuit to ground.
Figure 1 shows the OPA551 connected as a basic noninverting amplifier. The OPA551 can be used in virtually
any op amp configuration. OPA552 is designed for use in
configurations with gains of 5 or greater. Power supply
terminals should be bypassed with 0.1µF capacitors, or
greater, near the power supply pins. Be sure that the capacitors are appropriately rated for the power supply voltage
used. The OPA551 and OPA552 can supply output currents
up to 200mA with excellent performance.
THERMAL PROTECTION
The OPA551 and OPA552 have thermal shutdown circuitry
that protects the amplifier from damage caused by overload
conditions. The thermal protection circuitry disables the
output when the junction temperature reaches approximately
160°C, allowing the device to cool. When the junction
temperature cools to approximately 140°C, the output circuitry is automatically re-enabled.
V+
10µF
G = 1+
+
R2
R1
0.1µF
R2
R1
VO
OPA551
VIN
The thermal shutdown function is not intended to replace
proper heat sinking. Activation of the thermal shutdown
circuitry is an indication of excessive power dissipation or
an inadequate heat sink. Continuously running the amplifier
into thermal shutdown can degrade reliability.
ZL
Flag
The Thermal Shutdown Indicator (“flag”) pin can be monitored to determine if shutdown is occurring. During normal
operation, the current output from the flag pin is typically
50nA. During shutdown, the current output from the flag pin
increases to 120µA (typical). This current output allows for
easy interfacing to external logic. See Figure 2 for two
examples implementing this function.
(optional)
0.1µF
10µF
+
V–
FIGURE 1. Basic Circuit Connections.
VOUT
OPA551
Flag
80µA to
160µA
HCT logic has relatively wellcontrolled logic level. A properly
chosen resistor value can
guarantee proper logic high level
throughout the full range of flag
output current.
VOUT
OPA551
VLOGIC
+5V
HP5082-2835
Interface to virtually any CMOS
logic gate by choosing resistor
value that provides a guaranteed
logic high voltage with the
minimum (80µA) flag current. A
diode clamp to the logic supply
voltage assures that the CMOS
is not damaged by overdrive.
HCT
27kΩ
Logic
Ground
Interfacing with HCT Logic
CMOS
47kΩ
Logic
Ground
Interfacing with CMOS Logic
FIGURE 2. Thermal Shutdown Indicator.
®
9
OPA551, OPA552
POWER SUPPLIES
The power being dissipated (PD) in the output transistor of
the amplifier can be calculated:
The OPA551 and OPA552 may be operated from power
supplies of ±4V to ±30V, or a total of 60V with excellent
performance. Most behavior remains unchanged throughout
the full operating voltage range. Parameters that vary significantly with operating voltage are shown in the Typical
Performance Curves.
PD(output stage) = IO • (VS – VO) = 25mA • (30 – 15) = 375mW
PD(total) = PD(internal) + PD(output stage) = 432mW + 375mW = 807mW
The resulting junction temperature can be calculated:
TJ = TA + PD θJA
For applications that do not require symmetrical output
voltage swing, power supply voltages do not need to be
equal. The OPA551 and OPA552 can operate with as little
as 8V between the supplies or with up to 60V between the
supplies. For example, the positive supply could be set to
50V with the negative supply at –10V or vice-versa.
TJ = 40°C + 807mW • 100°C/W = 120.7°C
Where,
TJ = junction temperature (°C)
TA = ambient temperature (°C)
θJA = junction-to-air thermal resistance (°C/W)
The SO-8 package outline shows three negative supply (V–)
pins. These pins are internally connected for improved thermal
performance. Pin 4 is to be used as the primary current
carrier for the negative supply. It is recommended that
pins 1 and 5 not be directly connected to V– but, instead
be connected to a thermal mass. DO NOT lay out the PC
board to use pins 1 and 5 as feedthroughs to the negative
supply. Doing so can result in a reduction of performance.
For the DDPAK package, the θJA is 65°C/W with no heat
sinking, resulting in a junction temperature of 92.5°C.
To estimate the margin of safety in a complete design
(including heat sink), increase the ambient temperature until
the thermal protection is activated. Use worst-case load and
signal conditions. For good reliability, the thermal protection should trigger more than +35°C above the maximum
expected ambient condition of your application. This ensures a maximum junction temperature of +125°C at the
maximum expected ambient condition.
The tab of the DDPAK-7 package is electrically connected
to the negative supply (V–), however, this connection should
not be used to carry current. For best thermal performance,
the tab should be soldered directly to the circuit board
copper area (see heat sink text).
If the OPA551 or OPA552 is to be used in an application
requiring more than 0.5W continuous power dissipation, it
is recommended that the DDPAK package option be used.
The DDPAK has superior thermal dissipation characteristics and is more easily adapted to a heat sink.
POWER DISSIPATION
Internal power dissipation of these op amps can be quite
large. Many of the specifications for the OPA551 and
OPA552 are for a specified junction temperature. If the
device is not subjected to internal self-heating, the junction
temperature will be the same as the ambient. However, in
practical applications, the device will self-heat and the junction temperature will be significantly higher than ambient.
After junction temperature has been established, performance parameters that vary with junction temperature can be
determined from the performance curves. The following
calculation can be performed to establish junction temperature as a function of ambient temperature and the conditions
of the application.
Operation from a single power supply (or unbalanced power
supplies) can produce even larger power dissipation since a
larger voltage can be impressed across the conducting output
transistor. Consult Application Bulletin AB-039 for further
information on how to calculate or measure power dissipation.
Power dissipation can be minimized by using the lowest
possible supply voltage. For example, with a 200mA load,
the output will swing to within 3.5V of the power supply
rails. Power supplies set to no more than 3.5V above the
maximum output voltage swing required by the application
will minimize the power dissipation.
SAFE OPERATING AREA
Consider the OPA551 in a circuit configuration where the
load is 600Ω and the output voltage is 15V. The supplies are
at ±30V and the ambient temperature (TA) is 40°C. The θJA
for the 8-pin DIP package is 100°C/W.
The Safe Operating Area (SOA curves, Figures 3, 4, and 5)
shows the permissible range of voltage and current. The
curves shown represent devices soldered to a circuit board
with no heat sink. The safe output current decreases as the
voltage across the output transistor (VS – VO) increases. For
further insight on SOA, consult Application Bulletin AB-039.
First, the internal heating of the op amp is as follows:
PD(internal) = IQ • VS = 7.2mA • 60V = 432mW
The output current (IO) can be calculated:
Output short circuits are a very demanding case for SOA.
A short circuit to ground forces the full power supply
voltage (V+ or V–) across the conducting transistor and
produces a typical output current of 380mA. With ±30V
IO = VOUT /RL = 15V/600Ω = 25mA
®
OPA551, OPA552
10
HEAT SINKING
power supplies, this creates an internal dissipation of 11.4W.
This far exceeds the maximum rating and is not recommended. If operation in this region is unavoidable, use the
DDPAK with a heat sink.
Power dissipated in the OPA551 or OPA552 will cause the
junction temperature to rise. For reliable operation, the
junction temperature should be limited to +125°C. Many
applications will require a heat sink to assure that the
maximum operating junction temperature is not exceeded.
The heat sink required depends on the power dissipated and
on ambient conditions.
SAFE OPERATING AREA—8-PIN DIP
1000
For heat sinking purposes, the tab of the DDPAK is typically
soldered directly to a circuit board copper area. Increasing
the copper area improves heat dissipation. Figure 6 shows
typical thermal resistance from junction-to-ambient as a
function of copper area.
25°C
IO (mA)
100
125°C
10
85°C
Depending on conditions, additional heat sinking may be
required. Aavid Thermal Products Inc. manufactures surface-mountable heat sinks designed specifically for use with
DDPAK packages. Further information is available on
Aavid’s web site, www.aavid.com.
1
0.1
1
10
100
| VS | – | VO | (V)
To estimate the margin of safety in a complete design
(including heat sink), increase the ambient temperature until
the thermal protection is activated. Use worst-case load and
signal conditions. For good reliability, the thermal protection should trigger more than +25°C above the maximum
expected ambient condition of your application. This produces a junction temperature of +125°C at the maximum
expected ambient condition.
FIGURE 3. DIP-8 Safe Operating Area.
SAFE OPERATING AREA—SO-8
1000
25°C
THERMAL RESISTANCE vs
CIRCUIT BOARD COPPER AREA
125°C
10
50
85°C
Thermal Resistance, θJA (°C/W)
IO (mA)
100
1
0.1
1
10
100
| VS | – | VO | (V)
FIGURE 4. SO-8 Safe Operating Area.
OPA551, OPA552
Surface-Mount Package
1oz. copper
40
30
20
10
0
0
1
2
3
4
5
Copper Area (inches2)
SAFE OPERATING AREA—DDPAK
1000
25°C
25°C
1" Copper
Circuit Board Copper Area
IO (mA)
100
125°C
10
125°C
1" Copper
85°C
1
0.1
1
10
100
OPA551, OPA552
Surface-Mount Package
| VS | – | VO | (V)
FIGURE 5. DDPAK-7 Safe Operating Area.
FIGURE 6. DDPAK Thermal Resistance vs Circuit Board
Copper Area.
®
11
OPA551, OPA552
CAPACITIVE LOADS
can be used to boost output current. The circuit in Figure 10
is capable of supplying output currents up to 1A. Alternatively, the OPA547, OPA548, and OPA549 series power op
amps should be considered for high output current drive,
along with programmable current limit and output disable
capability.
The dynamic characteristics of the OPA551 and OPA552
have been optimized for commonly encountered gains, loads,
and operating conditions. The combination of low closedloop gain and capacitive load will decrease the phase margin
and may lead to gain peaking or oscillations. Figure 7 shows
a circuit that preserves phase margin with capacitive load.
Figure 8 shows the small-signal step response for the circuit
in Figure 7. Consult Application Bulletin AB-028 for more
information.
R1
R2
“MASTER”
+30V
RS(1)
10Ω
OPA551
VIN
OPA551
RG
4kΩ
RS(1)
10Ω
10nF
RF
4kΩ
OPA551
VI
CS
1.8nF
CF
220pF
RL
“SLAVE”
–30V
NOTE: (1) RS resistors minimize the circulating
current that can flow between the two devices
due to VOS errors.
FIGURE 7. Driving Large Capacitive Loads.
SMALL-SIGNAL STEP RESPONSE
OPA551, G = –1, CL = 10nF
FIGURE 9. Parallel Amplifers Increase Output Current Capability.
OPA551
20mV/div
R1
R2
+30V
TIP29C
CF
R3(1)
100Ω
Time (2.5µs/div)
R4
0.2Ω
VO
OPA551
VIN
R4
0.2Ω
FIGURE 8. Small-Signal Step Response for Figure 7.
LOAD
TIP30C
INCREASING OUTPUT CURRENT
In those applications where the 200mA of output current is
not sufficient to drive the desired load, output current can be
increased by connecting two or more OPA551s or OPA552s
in parallel as shown in Figure 9. Amplifier A1 is the
“master” amplifier and may be configured in virtually an op
amp circuit. Amplifier A2, the “slave”, is configured as a
unity gain buffer. Alternatively, external output transistors
–30V
NOTE: (1) R3 provides current limit and allows the amplifier to
drive the load when the output is between 0.7V and –0.7V.
FIGURE 10. External Output Transistors Boost Output Current Up to 1 Amp.
®
OPA551, OPA552
12
INPUT PROTECTION
providing the full slew rate at the output and an exceptional distortion performance due to increased loop gain at
frequencies below NG1 • Z0. The capacitor values shown
in Figure 11 are calculated for NG1 = 2 and NG2 = 10 with
no adjustment for parasitics.
The OPA551 and OPA552 feature internal clamp diodes
to protect the inputs when voltages beyond the supply rails
are encountered. However, input current should be limited
to 5mA. In some cases, an external series resistor may be
required. Many input signals are inherently current-limtied,
therefore, a limiting resistor may not be required. Please
consider that a “large” series resistor, in conjunction with
the input capacitance, can affect stability.
Actual circuit values can be optimized by check the
small-signal step response with actual load conditions.
Figure 12 shows the small-signal step response of this
OPA552, G = –1 circuit with a 500pF load. It is wellbehaved with no tendency to oscillate. If CS and CF were
removed, the circuit would be unstable.
USING THE OPA552 IN LOW GAINS
The OPA552 family is intended for applications with
signal gains of 5 or greater, but it is possible to take
advantage of their high slew rate in lower gains using an
external compensation technique in an inverting configuration. This technique maintains low noise characteristics
of the OPA552 architecture at low frequencies. Depending
on the application, a small increase in high frequency
noise may result. This technique shapes the loop gain for
good stability while giving an easily controlled secondorder low-pass frequency response.
+30V
OPA552
RG
1kΩ
VOUT
RF
1kΩ
VIN
CS
1.88nF
Considering only the noise gain (non-inverting signal
gain) for the circuit of Figure 11, the low frequency noise
gain (NG1) will be set by the resistor ratios, while the high
frequency noise gain (NG2) will be set by the capacitor
ratios. The capacitor values set both the transition frequencies and the high frequency noise gain. If this noise
gain, determined by NG2 = 1 + CS/CF, is set to a value
greater than the recommended minimum stable gain for
the op amp and the noise gain pole, set by 1/RFCF, is
placed correctly, a very well controlled, 2nd-order lowpass frequency response will result.
CF
208pF
–30V
NG1 = 1 + RF/RG = 2
NG2 = 1 + CS/CF = 10
FIGURE 11. Compensation of the OPA552 for G = 1.
To choose the values for both CS and CF, two parameters
and only three equations need to be solved. First, the
target for the high frequency noise gain (NG2) should be
greater than the minimum stable gain for the OPA552. In
the circuit in Figure 11, a target NG2 of 10 is used.
Second, the signal gain of –1 shown in Figure 11 sets the
low frequency noise gain to NG1 = 1 + RF/RG (=2 in this
example). Using these two gains, knowing the Gain Bandwidth Product (GBP) for the OPA552 (12MHz), and
targeting a maximally flat 2nd-order, low-pass Butterworth
frequency response (Q = 0.707), the key frequency in the
compensation can be found.
SMALL-SIGNAL STEP RESPONSE
OPA552, G = –1, CL = 500pF
20mV/div
OPA552
For the values shown in Figure 11, the f–3dB will be
approximately 956kHz. This is less than that predicted by
simply dividing the GBP by NG1. The compensation
network controls the bandwidth to a lower value while
Time (1µs/div)
FIGURE 12. Small-Signal Step Response for Figure 11.
®
13
OPA551, OPA552
OFFSET VOLTAGE ERROR CALCULATION
The offset voltage (VOS) of the OPA51 and OPA552 is
specified with a ±30V power supply and the commonmode voltage centered between the supplies (VS/2 =
0V). Additional specifications for power supply rejection and common-mode rejection are provided to allow
the user to easily calculate worst-case excepted offset
under the conditions of a given application.
Power Supply Rejection Ratio (PSRR) is specified in
µV/V. For the OPA551 and OPA552, worst-case PSRR
is 30µV/V, which means for each volt of change in total
power supply voltage, the offset may shift by up to
30µV/V. Common-Mode Rejection Ratio (CMRR) is
specified in dB, which can be converted to µV/V using
the following equation:
CMRR in (V/V) = 10[(CMRR in dB)/–20]
calculate excursions from the specified offset voltage
under different applications conditions. For example, a
common application might configure the amplifier with
a –48 single supply with –6V common-mode. This
configuration represents a 12V variation in power supply: ±30V or 60V in the offset specification versus 48V
in the application. In addition, this configuration has an
18V variation in common-mode voltage: VS/2 = –24V is
the specification for these power supplies, but the common-mode voltage is –6V in the application.
Calculation of the worst-case expected offset would be
as follows:
Worst-case VOS =
(2)
maximum specified VOS
+ (power supply variation • PSRR
+ (common-mode variation • CMRR)
(1)
For the OPA551 and OPA552, the worst-case CMRR at
±30mV supply over the full common-mode range is
96dB, or approxmately 15.8µV/V. This means that for
every volt of change in common-mode, the offset may
shift up to 15.8µV. These numbers can be used to
VOSwc = 5mV + (12V • 30µV/V) + (18V • 15.8µV/V)
= ±5.64mV
®
OPA551, OPA552
14
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