AD8618_15 [ADI]
Precision, 20 MHz, CMOS, Rail-to-Rail;型号: | AD8618_15 |
厂家: | ADI |
描述: | Precision, 20 MHz, CMOS, Rail-to-Rail |
文件: | 总20页 (文件大小:449K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
Precision, 20 MHz, CMOS, Rail-to-Rail
Input/Output Operational Amplifiers
Data Sheet
AD8615/AD8616/AD8618
FEATURES
PIN CONFIGURATIONS
Low offset voltage: 65 μV maximum
Single-supply operation: 2.7 V to 5.0 V
Low noise: 8 nV/√Hz
Wide bandwidth: >20 MHz
Slew rate: 12 V/μs
5
V+
OUT
V–
1
2
3
AD8615
TOP VIEW
(Not to Scale)
4
–IN
+IN
High output current: 150 mA
No phase reversal
Figure 1. 5-Lead TSOT-23 (UJ-5)
Low input bias current: 1 pA
Low supply current: 2 mA
Unity-gain stable
OUT A
–IN A
+IN A
V–
1
2
3
4
8
7
6
5
V+
AD8616
OUT B
–IN B
+IN B
TOP VIEW
(Not to Scale)
APPLICATIONS
Figure 2. 8-Lead MSOP (RM-8)
Barcode scanners
Battery-powered instrumentation
Multipole filters
Sensors
ASIC input or output amplifiers
Audio
Photodiode amplification
OUT A
–IN A
+IN A
V–
1
2
3
4
8
7
6
5
V+
AD8616
OUT B
–IN B
+IN B
TOP VIEW
(Not to Scale)
Figure 3. 8-Lead SOIC (R-8)
OUT A
–IN A
+IN A
V+
+IN B
–IN B
OUT B
1
14
OUT D
–IN D
+IN D
V–
+IN C
–IN C
OUT C
GENERAL DESCRIPTION
AD8618
TOP VIEW
(Not to Scale)
The AD8615/AD8616/AD8618 are single/dual/quad, rail-to-
rail, input and output, single-supply amplifiers featuring very
low offset voltage, wide signal bandwidth, and low input voltage
and current noise. The parts use a patented trimming technique
that achieves superior precision without laser trimming. The
AD8615/AD8616/AD8618 are fully specified to operate from
2.7 V to 5 V single supplies.
7
8
Figure 4. 14-Lead TSSOP (RU-14)
OUT A
–IN A
+IN A
V+
1
2
3
4
5
6
7
14 OUT D
13 –IN D
12 +IN D
11 V–
AD8618
TOP VIEW
The combination of >20 MHz bandwidth, low offset, low noise,
and low input bias current makes these amplifiers useful in a
wide variety of applications. Filters, integrators, photodiode
amplifiers, and high impedance sensors all benefit from the
combination of performance features. AC applications benefit from
the wide bandwidth and low distortion. The AD8615/AD8616/
AD8618 offer the highest output drive capability of the DigiTrim®
family, which is excellent for audio line drivers and other low
impedance applications.
(Not to Scale)
+IN B
–IN B
OUT B
10 +IN C
9
8
–IN C
OUT C
Figure 5. 14-Lead SOIC (R-14)
The AD8615/AD8616/AD8618 are specified over the extended
industrial temperature range (−40°C to +125°C). The AD8615
is available in 5-lead TSOT-23 package. The AD8616 is available
in 8-lead MSOP and narrow SOIC surface-mount packages; the
MSOP version is available in tape and reel only. The AD8618 is
available in 14-lead SOIC and TSSOP packages.
Applications for the parts include portable and low powered
instrumentation, audio amplification for portable devices,
portable phone headsets, bar code scanners, and multipole
filters. The ability to swing rail-to-rail at both the input and
output enables designers to buffer CMOS ADCs, DACs, ASICs,
and other wide output swing devices in single-supply systems.
Rev. G
Document Feedback
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks arethe property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 ©2004–2014 Analog Devices, Inc. All rights reserved.
Technical Support
www.analog.com
AD8615/AD8616/AD8618
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Output Phase Reversal............................................................... 11
Driving Capacitive Loads.......................................................... 11
Overload Recovery Time .......................................................... 12
D/A Conversion ......................................................................... 12
Low Noise Applications............................................................. 12
High Speed Photodiode Preamplifier...................................... 13
Active Filters ............................................................................... 13
Power Dissipation....................................................................... 13
Power Calculations for Varying or Unknown Loads............. 14
Outline Dimensions....................................................................... 15
Ordering Guide .......................................................................... 17
Applications....................................................................................... 1
General Description......................................................................... 1
Pin Configurations ........................................................................... 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 5
Thermal Resistance ...................................................................... 5
ESD Caution.................................................................................. 5
Typical Performance Characteristics ............................................. 6
Applications Information .............................................................. 11
Input Overvoltage Protection ................................................... 11
REVISION HISTORY
6/14—Rev. F to Rev. G
6/05—Rev. B to Rev. C
Changes to Input Overvoltage Protection Section..................... 11
Change to Table 1 ..............................................................................3
Change to Table 2 ..............................................................................4
Change to Figure 20 ..........................................................................8
3/14—Rev. E to Rev. F
Changes to Differential Input Voltage Parameter, Table 3.......... 5
Updated Outline Dimensions ....................................................... 15
Changes to Ordering Guide .......................................................... 17
1/05—Rev. A to Rev. B
Added AD8615 ...................................................................Universal
Changes to Figure 12.........................................................................8
Deleted Figure 19; Renumbered Subsequently..............................8
Changes to Figure 20.........................................................................9
Changes to Figure 29...................................................................... 10
Changes to Figure 31...................................................................... 11
Deleted Figure 34; Renumbered Subsequently........................... 11
Deleted Figure 35; Renumbered Subsequently........................... 35
9/08—Rev. D to Rev. E
Changes to General Description Section ...................................... 1
Updated Outline Dimensions ....................................................... 15
Changes to Ordering Guide .......................................................... 17
5/08—Rev. C to Rev. D
Changes to Layout ............................................................................ 1
Changes to Figure 38...................................................................... 11
Changes to Figure 44 and Figure 45............................................. 13
Changes to Layout .......................................................................... 15
Changes to Layout .......................................................................... 16
4/04—Rev. 0 to Rev. A
Added AD8618 ...................................................................Universal
Updated Outline Dimensions....................................................... 16
1/04—Revision 0: Initial Version
Rev. G | Page 2 of 20
Data Sheet
AD8615/AD8616/AD8618
SPECIFICATIONS
VS = 5 V, V CM = VS/2, TA = 25°C, unless otherwise noted.
Table 1.
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
INPUT CHARACTERISTICS
Offset Voltage, AD8616/AD8618
Offset Voltage, AD8615
VOS
VS = 3.5 V at VCM = 0.5 V and 3.0 V
23
23
80
60
100
500
800
7
µV
µV
µV
µV
µV/°C
µV/°C
pA
VCM = 0 V to 5 V
−40°C < TA < +125°C
−40°C < TA < +125°C
Offset Voltage Drift, AD8616/AD8618
Offset Voltage Drift, AD8615
Input Bias Current
∆VOS/∆T
IB
1.5
3
0.2
10
1
−40°C < TA < +85°C
−40°C < TA < +125°C
50
550
0.5
50
250
5
pA
pA
pA
pA
pA
V
Input Offset Current
IOS
0.1
−40°C < TA < +85°C
−40°C < TA < +125°C
Input Voltage Range
0
Common-Mode Rejection Ratio
Large Signal Voltage Gain
Input Capacitance
CMRR
AVO
CDIFF
CCM
VCM = 0 V to 4.5 V
RL = 2 kΩ, VO = 0.5 V to 5 V
80
105
100
1500
2.5
dB
V/mV
pF
6.7
pF
OUTPUT CHARACTERISTICS
Output Voltage High
VOH
IL = 1 mA
IL = 10 mA
−40°C < TA < +125°C
IL = 1 mA
IL = 10 mA
4.98
4.88
4.7
4.99
4.92
V
V
V
mV
mV
mV
mA
Ω
Output Voltage Low
VOL
7.5
70
15
100
200
−40°C < TA < +125°C
Output Current
Closed-Loop Output Impedance
POWER SUPPLY
IOUT
ZOUT
150
3
f = 1 MHz, AV = 1
Power Supply Rejection Ratio
Supply Current per Amplifier
PSRR
ISY
VS = 2.7 V to 5.5 V
VO = 0 V
−40°C < TA < +125°C
70
90
1.7
dB
mA
mA
2
2.5
DYNAMIC PERFORMANCE
Slew Rate
Settling Time
Gain Bandwidth Product
Phase Margin
SR
tS
GBP
Øm
RL = 2 kΩ
To 0.01%
12
<0.5
24
V/µs
µs
MHz
Degrees
63
NOISE PERFORMANCE
Peak-to-Peak Noise
Voltage Noise Density
en p-p
en
0.1 Hz to 10 Hz
f = 1 kHz
f = 10 kHz
f = 1 kHz
f = 10 kHz
f = 100 kHz
2.4
10
7
0.05
−115
−110
µV
nV/√Hz
nV/√Hz
pA/√Hz
dB
Current Noise Density
Channel Separation
in
CS
dB
Rev. G | Page 3 of 20
AD8615/AD8616/AD8618
Data Sheet
VS = 2.7 V, VCM = VS/2, TA = 25°C, unless otherwise noted.
Table 2.
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
INPUT CHARACTERISTICS
Offset Voltage, AD8616/AD8618
Offset Voltage, AD8615
VOS
VS = 3.5 V at VCM = 0.5 V and 3.0 V
23
23
80
65
µV
µV
µV
µV
100
500
800
7
10
1
VCM = 0 V to 2.7 V
−40°C < TA < +125°C
−40°C < TA < +125°C
Offset Voltage Drift, AD8616/AD8618
Offset Voltage Drift, AD8615
Input Bias Current
∆VOS/∆T
IB
1.5
3
0.2
µV/°C
µV/°C
pA
−40°C < TA < +85°C
−40°C < TA < +125°C
50
pA
pA
pA
pA
pA
V
550
0.5
50
250
2.7
Input Offset Current
IOS
0.1
−40°C < TA < +85°C
−40°C < TA < +125°C
Input Voltage Range
0
Common-Mode Rejection Ratio
Large Signal Voltage Gain
Input Capacitance
CMRR
AVO
CDIFF
CCM
VCM = 0 V to 2.7 V
RL = 2 kΩ, VO = 0.5 V to 2.2 V
80
55
100
150
2.5
dB
V/mV
pF
7.8
pF
OUTPUT CHARACTERISTICS
Output Voltage High
VOH
VOL
IL = 1 mA
−40°C < TA < +125°C
IL = 1 mA
2.65
2.6
2.68
11
V
V
mV
mV
mA
Ω
Output Voltage Low
25
30
−40°C < TA < +125°C
Output Current
Closed-Loop Output Impedance
POWER SUPPLY
IOUT
ZOUT
50
3
f = 1 MHz, AV = 1
Power Supply Rejection Ratio
Supply Current per Amplifier
PSRR
ISY
VS = 2.7 V to 5.5 V
VO = 0 V
−40°C < TA < +125°C
70
90
1.7
dB
mA
mA
2
2.5
DYNAMIC PERFORMANCE
Slew Rate
Settling Time
Gain Bandwidth Product
Phase Margin
SR
tS
GBP
Øm
RL = 2 kΩ
To 0.01%
12
<0.3
23
V/µs
µs
MHz
Degrees
42
NOISE PERFORMANCE
Peak-to-Peak Noise
Voltage Noise Density
en p-p
en
0.1 Hz to 10 Hz
f = 1 kHz
f = 10 kHz
f = 1 kHz
f = 10 kHz
f = 100 kHz
2.1
10
7
0.05
−115
−110
µV
nV/√Hz
nV/√Hz
pA/√Hz
dB
Current Noise Density
Channel Separation
in
CS
dB
Rev. G | Page 4 of 20
Data Sheet
AD8615/AD8616/AD8618
ABSOLUTE MAXIMUM RATINGS
Table 3.
THERMAL RESISTANCE
θJA is specified for the worst-case conditions, that is, θJA is specified
for a device soldered in a circuit board for surface-mount packages.
Parameter
Rating
Supply Voltage
6 V
Input Voltage
GND to VS
6 V
Indefinite
−65°C to +150°C
−40°C to +125°C
300°C
Table 4.
Package Type
Differential Input Voltage
Output Short-Circuit Duration to GND
Storage Temperature Range
Operating Temperature Range
Lead Temperature (Soldering, 60 sec)
Junction Temperature
θJA
θJC
61
45
43
36
35
Unit
°C/W
°C/W
°C/W
°C/W
°C/W
5-Lead TSOT-23 (UJ)
8-Lead MSOP (RM)
8-Lead SOIC (R)
14-Lead SOIC (R)
14-Lead TSSOP (RU)
207
210
158
120
180
150°C
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ESD CAUTION
Rev. G | Page 5 of 20
AD8615/AD8616/AD8618
Data Sheet
TYPICAL PERFORMANCE CHARACTERISTICS
2200
350
300
250
200
150
100
50
V
T
V
= 5V
= 25°C
V = ±2.5V
S
S
A
2000
1800
1600
1400
1200
1000
800
= 0V TO 5V
CM
600
400
200
0
0
–700
–500
–300
–100
100
300
V)
500
700
0
25
50
75
100
125
TEMPERATURE (°-C)
OFFSET VOLTAGE (
µ
Figure 9. Input Bias Current vs. Temperature
Figure 6. Input Offset Voltage Distribution
22
20
18
16
14
12
10
8
1000
100
10
V
T
= 5V
= 25°C
S
A
V
T
= ±2.5V
= –40°C TO +125°C
= 0V
S
A
V
CM
SOURCE
SINK
6
1
4
2
0
0.1
0.001
0.01
0.1
1
10
100
0
2
4
6
8
10
12
I
(mA)
LOAD
TCV (µV/°C)
OS
Figure 10. Output Voltage to Supply Rail vs. Load Current
Figure 7. Offset Voltage Drift Distribution
500
400
120
100
80
60
40
20
0
V
T
= 5V
= 25°C
S
A
V
= 5V
S
300
10mA LOAD
200
100
0
–100
–200
–300
–400
–500
1mA LOAD
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
–40 –25 –10
5
20
35
50
65
80
95 110 125
COMMON-MODE VOLTAGE (V)
TEMPERATURE (°C)
Figure 8. Input Offset Voltage vs. Common-Mode Voltage
(200 Units, Five Wafer Lots Including Process Skews)
Figure 11. Output Saturation Voltage vs. Temperature
Rev. G | Page 6 of 20
Data Sheet
AD8615/AD8616/AD8618
120
100
80
60
40
20
0
100
225
V
= ±2.5V
= 25°C
= 63°
S
V
= ±2.5V
S
80
60
40
20
0
180
135
90
45
0
T
A
Ø
m
–20
–40
–60
–45
–90
–135
–80
–180
–225
–100
1M
10M
60M
1k
10k
100k
1M
10M
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 15. CMRR vs. Frequency
Figure 12. Open-Loop Gain and Phase vs. Frequency
120
100
80
60
40
20
0
5.0
V
= ±2.5V
S
V
V
T
R
A
= 5.0V
= 4.9V p-p
= 25°C
= 2kΩ
= 1
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
S
IN
A
L
V
1k
10k
100k
1M
10M
1k
10k
100k
1M
10M
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 13. Closed-Loop Output Voltage Swing vs. Frequency
Figure 16. PSRR vs. Frequency
100
90
80
70
60
50
40
30
20
10
0
50
45
40
35
30
25
20
15
10
5
V
= ±2.5V
S
V = 5V
S
R
= ∞
L
T
A
= 25°C
= 1
A
V
A
= 100
A = 1
V
–OS
+OS
V
A
= 10
V
0
1k
10k
100k
1M
10M
100M
10
100
1000
FREQUENCY (Hz)
CAPACITANCE (pF)
Figure 14. Output Impedance vs. Frequency
Figure 17. Small-Signal Overshoot vs. Load Capacitance
Rev. G | Page 7 of 20
AD8615/AD8616/AD8618
Data Sheet
2.4
2.2
2.0
V
= 5V
= 10kΩ
= 200pF
= 1
S
R
C
A
L
L
V
V
= 2.7V
S
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
V
= 5V
S
–40 –25 –10
5
20
35
50
65
C)
80
95 110 125
TIME (1µs/DIV)
TEMPERATURE (
°
Figure 21. Small Signal Transient Response
Figure 18. Supply Current vs. Temperature
2000
1800
1600
1400
1200
1000
800
V
= 5V
S
R
C
A
= 10kΩ
= 200pF
= 1
L
L
V
600
400
200
0
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
TIME (1s/DIV)
SUPPLY VOLTAGE (V)
Figure 19. Supply Current per Amplifier vs. Supply Voltage
Figure 22. Large Signal Transient Response
0.1
0.01
1k
V
V
= ±2.5V
= ±1.35V
V
V
A
= ±2.5V
= 0.5V rms
= 1
S
S
S
IN
V
BW = 22kHz
= 100kΩ
R
L
100
0.001
0.0001
10
1
10
100
1k
10k
100k
20
100
1k
20k
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 23. THD + N vs. Frequency
Figure 20. Voltage Noise Density vs. Frequency
Rev. G | Page 8 of 20
Data Sheet
AD8615/AD8616/AD8618
500
400
V
V
A
= ±2.5V
= 2V p-p
= 10
S
V
T
= 2.7V
= 25°C
S
A
IN
V
300
200
100
0
–100
–200
–300
–400
–500
0
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
2.7
TIME (200ns/DIV)
COMMON-MODE VOLTAGE (V)
Figure 24. Settling Time
Figure 27. Input Offset Voltage vs. Common-Mode Voltage
(200 Units, Five Wafer Lots Including Process Skews)
500
400
V
= 2.7V
S
V
T
= 3.5V
= 25°C
S
A
300
200
100
0
–100
–200
–300
–400
–500
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
TIME (1s/DIV)
COMMON-MODE VOLTAGE (V)
Figure 25. 0.1 Hz to 10 Hz Input Voltage Noise
Figure 28. Input Offset Voltage vs. Common-Mode Voltage
(200 Units, Five Wafer Lots Including Process Skews)
1000
1400
1200
1000
800
600
400
200
0
V
= 2.7V
S
V
T
= ±1.35V
= 25°C
S
T
= 25°C
A
A
V
= 0V TO 2.7V
CM
100
10
SOURCE
SINK
1
0.1
0.001
–700
–500
–300
–100
100
300
500
700
0.01
0.1
(mA)
1
10
I
LOAD
OFFSET VOLTAGE (µV)
Figure 29. Output Voltage to Supply Rail vs. Load Current
Figure 26. Input Offset Voltage Distribution
Rev. G | Page 9 of 20
AD8615/AD8616/AD8618
Data Sheet
18
50
45
40
35
30
25
20
15
10
5
V
= 2.7V
V
R
= ±1.35V
= ∞
S
S
16
14
12
10
8
L
T
A
= 25°C
= 1
V
@ 1mA LOAD
A
OH
V
V
@ 1mA LOAD
OL
–O
S
+OS
6
4
2
0
0
–40 –25 –10
5
20
35
50
65
80
95 110 125
10
100
CAPACITANCE (pF)
1000
TEMPERATURE (°C)
Figure 30. Output Saturation Voltage vs. Temperature
Figure 33. Small Signal Overshoot vs. Load Capacitance
100
225
V
= 2.7V
= 10kΩ
= 200pF
= 1
S
V
= ±1.35V
= 25°C
= 42°
S
R
C
A
L
L
V
80
60
40
20
0
180
135
90
T
A
Ø
m
45
0
–20
–40
–60
–45
–90
–135
–80
–180
–225
–100
1M
10M
60M
FREQUENCY (Hz)
TIME (1µs/DIV)
Figure 31. Open-Loop Gain and Phase vs. Frequency
Figure 34. Small Signal Transient Response
2.7
V
= 2.7V
= 10kΩ
= 200pF
= 1
S
R
C
A
L
L
V
V
V
= 2.7V
= 2.6V p-p
= 25°C
= 2kΩ
= 1
S
2.4
2.1
1.8
1.5
1.2
0.9
0.6
0.3
0
IN
T
A
R
A
L
V
1k
10k
100k
1M
10M
TIME (1µs/DIV)
FREQUENCY (Hz)
Figure 32. Closed-Loop Output Voltage Swing vs. Frequency
Figure 35. Large Signal Transient Response
Rev. G | Page 10 of 20
Data Sheet
AD8615/AD8616/AD8618
APPLICATIONS INFORMATION
This reduces the overshoot and minimizes ringing, which in
turn improves the frequency response of the AD8615/AD8616/
AD8618. One simple technique for compensation is the snubber,
which consists of a simple RC network. With this circuit in place,
output swing is maintained and the amplifier is stable at all gains.
INPUT OVERVOLTAGE PROTECTION
If the voltage applied at either input exceeds the supplies, place
external resistors in series with the inputs. The resistor values
can be determined by the equation
VIN VSY
5 mA
RS
Figure 38 shows the implementation of the snubber, which
reduces overshoot by more than 30% and eliminates ringing
that can cause instability. Using the snubber does not recover
the loss of bandwidth incurred from a heavy capacitive load.
The extremely low input bias current allows the use of larger
resistors, which allows the user to apply higher voltages at the
inputs. The use of these resistors adds thermal noise, which
contributes to the overall output voltage noise of the amplifier.
V
A
C
= ±2.5V
= 1
S
V
L
= 500pF
For example, a 10 kΩ resistor has less than 13 nV/√Hz of
thermal noise and less than 10 nV of error voltage at room
temperature.
OUTPUT PHASE REVERSAL
The AD8615/AD8616/AD8618 are immune to phase inversion,
a phenomenon that occurs when the voltage applied at the input of
the amplifier exceeds the maximum input common mode.
Phase reversal can cause permanent damage to the amplifier
and can create lock ups in systems with feedback loops.
TIME (2µs/DIV)
V
V
A
R
= ±2.5V
S
= 6V p-p
= 1
IN
Figure 37. Driving Heavy Capacitive Loads Without Compensation
V
L
= 10kΩ
V
EE
+
–
V
OUT
V–
V+
V
IN
200Ω
500pF
500pF
–
V
CC
200mV
Figure 38. Snubber Network
TIME (2ms/DIV)
V
= ±2.5V
= 1
= 200Ω
= 500pF
= 500pF
S
Figure 36. No Phase Reversal
A
R
C
C
V
S
S
L
DRIVING CAPACITIVE LOADS
Although the AD8615/AD8616/AD8618 are capable of driving
capacitive loads of up to 500 pF without oscillating, a large amount
of overshoot is present when operating at frequencies above
100 kHz. This is especially true when the amplifier is configured
in positive unity gain (worst case). When such large capacitive
loads are required, the use of external compensation is highly
recommended.
TIME (10µs/DIV)
Figure 39. Driving Heavy Capacitive Loads Using the Snubber Network
Rev. G | Page 11 of 20
AD8615/AD8616/AD8618
Data Sheet
5V
2.5V
OVERLOAD RECOVERY TIME
10µF
+
Overload recovery time is the time it takes the output of the
amplifier to come out of saturation and recover to its linear region.
Overload recovery is particularly important in applications where
small signals must be amplified in the presence of large transients.
Figure 40 and Figure 41 show the positive and negative overload
recovery times of the AD8616. In both cases, the time elapsed
before the AD8616 comes out of saturation is less than 1 μs. In
addition, the symmetry between the positive and negative recovery
times allows excellent signal rectification without distortion to the
output signal.
0.1µF
0.1µF
SERIAL
INTERFACE
V
REFF
REFS
DD
1/2
AD8616
CS
UNIPOLAR
OUTPUT
DIN
AD5542
V
OUT
SCLK
LDAC
DGND
AGND
Figure 42. Buffering DAC Output
LOW NOISE APPLICATIONS
V
R
A
= ±2.5V
= 10kΩ
= 100
S
L
Although the AD8618 typically has less than 8 nV/√Hz of voltage
noise density at 1 kHz, it is possible to reduce it further. A simple
method is to connect the amplifiers in parallel, as shown in
Figure 43. The total noise at the output is divided by the square
root of the number of amplifiers. In this case, the total noise is
approximately 4 nV/√Hz at room temperature. The 100 Ω
resistor limits the current and provides an effective output
resistance of 50 Ω.
V
+2.5V
V
= 50mV
IN
0V
0V
3
V
IN
R3
V+
V–
1
–50mV
R1
2
100Ω
10Ω
TIME (1µs/DIV)
R2
Figure 40. Positive Overload Recovery
1kΩ
3
2
R6
V+
V–
1
1
1
V
R
A
= ±2.5V
= 10kΩ
= 100
= 50mV
S
R4
L
100Ω
V
10Ω
V
IN
R5
–
2.5V
V
OUT
0V
0V
1kΩ
3
2
R9
V+
V–
R7
100Ω
10Ω
R8
1kΩ
+50mV
3
2
R12
V+
V–
R10
TIME (1µs/DIV)
100Ω
10Ω
Figure 41. Negative Overload Recovery
R11
D/A CONVERSION
1kΩ
The AD8616 can be used at the output of high resolution DACs.
The low offset voltage, fast slew rate, and fast settling time make
the part suitable to buffer voltage output or current output
DACs.
Figure 43. Noise Reduction
Figure 42 shows an example of the AD8616 at the output of the
AD5542. The AD8616’s rail-to-rail output and low distortion
help maintain the accuracy needed in data acquisition systems
and automated test equipment.
Rev. G | Page 12 of 20
Data Sheet
AD8615/AD8616/AD8618
10
0
HIGH SPEED PHOTODIODE PREAMPLIFIER
The AD8615/AD8616/AD8618 are excellent choices for I-to-V
conversions. The very low input bias, low current noise, and
high unity-gain bandwidth of the parts make them suitable,
especially for high speed photodiode preamplifiers.
–10
–20
–30
–40
In high speed photodiode applications, the diode is operated in a
photoconductive mode (reverse biased). This lowers the junction
capacitance at the expense of an increase in the amount of dark
current that flows out of the diode.
The total input capacitance, C1, is the sum of the diode and op
amp input capacitances. This creates a feedback pole that causes
degradation of the phase margin, making the op amp unstable.
Therefore, it is necessary to use a capacitor in the feedback to
compensate for this pole.
0.1
1
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 46. Second-Order Butterworth, Low-Pass Filter Frequency Response
To get the maximum signal bandwidth, select
POWER DISSIPATION
C1
2πR2 fU
Although the AD8615/AD8616/AD8618 are capable of providing
load currents up to 150 mA, the usable output, load current,
and drive capability are limited to the maximum power dissipation
allowed by the device package.
C2 =
where fU is the unity-gain bandwidth of the amplifier.
C2
In any application, the absolute maximum junction temperature
for the AD8615/AD8616/AD8618 is 150°C. This should never
be exceeded because the device could suffer premature failure.
Accurately measuring power dissipation of an integrated circuit
is not always a straightforward exercise; Figure 47 is a design aid
for setting a safe output current drive level or selecting a heat
sink for the package options available on the AD8616.
1.5
R2
–2.5V
–
V–
I
R
C
C
IN
D
SH
D
V+
+
+2.5V
–V
BIAS
Figure 44. High Speed Photodiode Preamplifier
ACTIVE FILTERS
1.0
SOIC
The low input bias current and high unity-gain bandwidth of
the AD8616 make it an excellent choice for precision filter design.
MSOP
Figure 45 shows the implementation of a second-order, low-pass
filter. The Butterworth response has a corner frequency of 100 kHz
0.5
and a phase shift of 90°. The frequency response is shown in
Figure 46.
2nF
0
0
20
40
60
80
100
120
140
V
EE
TEMPERATURE (°C)
Figure 47. Maximum Power Dissipation vs. Ambient Temperature
V–
V+
1.1k
Ω
1.1kΩ
These thermal resistance curves were determined using the
AD8616 thermal resistance data for each package and a
maximum junction temperature of 150°C.
V
IN
1nF
V
CC
Figure 45. Second-Order, Low-Pass Filter
Rev. G | Page 13 of 20
AD8615/AD8616/AD8618
Data Sheet
The following formula can be used to calculate the internal
junction temperature of the AD8615/AD8616/AD8618 for any
application:
Calculating Power by Measuring Ambient Temperature
and Case Temperature
The two equations for calculating the junction temperature are
TJ = PDISS × θJA + TA
TJ = TA + P θJA
where:
TJ = junction temperature
where:
TJ = junction temperature
TA = ambient temperature
P
DISS = power dissipation
θJA = package thermal resistance, junction-to-case
θJA = the junction-to-ambient thermal resistance
TA = ambient temperature of the circuit
TJ = TC + P θJC
To calculate the power dissipated by the AD8615/AD8616/
AD8618, use the following:
where:
TC is case temperature.
P
DISS = ILOAD × (VS – VOUT
where:
LOAD = output load current
VS = supply voltage
OUT = output voltage
)
θJA and θJC are given in the data sheet.
The two equations for calculating P (power) are
TA + P θJA = TC + P θJC
I
P = (TA − TC)/(θJC − θJA)
V
Once the power is determined, it is necessary to recalculate the
junction temperature to ensure that the temperature was not
exceeded.
The quantity within the parentheses is the maximum voltage
developed across either output transistor.
POWER CALCULATIONS FOR VARYING OR
UNKNOWN LOADS
The temperature should be measured directly on and near the
package but not touching it. Measuring the package can be
difficult. A very small bimetallic junction glued to the package
can be used, or an infrared sensing device can be used, if the
spot size is small enough.
Often, calculating power dissipated by an integrated circuit to
determine if the device is being operated in a safe range is not as
simple as it may seem. In many cases, power cannot be directly
measured. This may be the result of irregular output waveforms or
varying loads. Indirect methods of measuring power are required.
Calculating Power by Measuring Supply Current
If the supply voltage and current are known, power can be
calculated directly. However, the supply current can have a dc
component with a pulse directed into a capacitive load, which
can make the rms current very difficult to calculate. This difficulty
can be overcome by lifting the supply pin and inserting an rms
current meter into the circuit. For this method to work, make
sure the current is delivered by the supply pin being measured.
This is usually a good method in a single-supply system; however,
if the system uses dual supplies, both supplies may need to be
monitored.
There are two methods to calculate power dissipated by an
integrated circuit. The first is to measure the package temperature
and the board temperature. The second is to directly measure
the circuit’s supply current.
Rev. G | Page 14 of 20
Data Sheet
AD8615/AD8616/AD8618
OUTLINE DIMENSIONS
2.90 BSC
5
1
4
3
2.80 BSC
1.60 BSC
2
0.95 BSC
1.90
BSC
*
0.90 MAX
0.70 NOM
*
1.00 MAX
0.20
0.08
8°
4°
0°
0.10 MAX
0.50
0.30
0.60
0.45
0.30
SEATING
PLANE
*
COMPLIANT TO JEDEC STANDARDS MO-193-AB WITH
THE EXCEPTION OF PACKAGE HEIGHT AND THICKNESS.
Figure 48. 5-Lead Thin Small Outline Transistor Package [TSOT]
(UJ-5)
Dimensions shown in millimeters
3.20
3.00
2.80
8
1
5
4
5.15
4.90
4.65
3.20
3.00
2.80
PIN 1
IDENTIFIER
0.65 BSC
0.95
0.85
0.75
15° MAX
1.10 MAX
0.80
0.55
0.40
0.15
0.05
0.23
0.09
6°
0°
0.40
0.25
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 49. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
Rev. G | Page 15 of 20
AD8615/AD8616/AD8618
Data Sheet
5.00 (0.1968)
4.80 (0.1890)
8
1
5
4
6.20 (0.2441)
5.80 (0.2284)
4.00 (0.1574)
3.80 (0.1497)
0.50 (0.0196)
0.25 (0.0099)
1.27 (0.0500)
BSC
45°
1.75 (0.0688)
1.35 (0.0532)
0.25 (0.0098)
0.10 (0.0040)
8°
0°
0.51 (0.0201)
0.31 (0.0122)
COPLANARITY
0.10
1.27 (0.0500)
0.40 (0.0157)
0.25 (0.0098)
0.17 (0.0067)
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MS-012-AA
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
Figure 50. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body (R-8)
Dimensions shown in millimeters and (inches)
8.75 (0.3445)
8.55 (0.3366)
8
7
14
1
6.20 (0.2441)
5.80 (0.2283)
4.00 (0.1575)
3.80 (0.1496)
1.27 (0.0500)
0.50 (0.0197)
0.25 (0.0098)
45°
BSC
1.75 (0.0689)
1.35 (0.0531)
0.25 (0.0098)
0.10 (0.0039)
8°
0°
COPLANARITY
0.10
SEATING
PLANE
1.27 (0.0500)
0.40 (0.0157)
0.51 (0.0201)
0.31 (0.0122)
0.25 (0.0098)
0.17 (0.0067)
COMPLIANT TO JEDEC STANDARDS MS-012-AB
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
Figure 51. 14-Lead Standard Small Outline Package [SOIC_N]
Narrow Body (R-14)
Dimensions shown in millimeters and (inches)
5.10
5.00
4.90
14
8
7
4.50
4.40
4.30
6.40
BSC
1
PIN 1
0.65 BSC
1.05
1.00
0.80
1.20
MAX
0.20
0.09
0.75
8°
0°
0.15
0.05
COPLANARITY
0.10
0.60
0.45
SEATING
PLANE
0.30
0.19
COMPLIANT TO JEDEC STANDARDS MO-153-AB-1
Figure 52. 14-Lead Thin Shrink Small Outline Package [TSSOP]
(RU-14)
Dimensions shown in millimeters
Rev. G | Page 16 of 20
Data Sheet
AD8615/AD8616/AD8618
ORDERING GUIDE
Model1
AD8615AUJZ-R2
AD8615AUJZ-REEL
AD8615AUJZ-REEL7
AD8616ARMZ
AD8616ARMZ-REEL
AD8616AR
AD8616ARZ
AD8616ARZ-REEL
AD8616ARZ-REEL7
AD8618ARZ
AD8618ARZ-REEL
AD8618ARZ-REEL7
AD8618ARUZ
Temperature Range
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
Package Description
5-Lead TSOT-23
5-Lead TSOT-23
5-Lead TSOT-23
8-Lead MSOP
Package Option
UJ-5
UJ-5
Branding
BKA
BKA
UJ-5
BKA
RM-8
RM-8
R-8
R-8
R-8
A0K
A0K
8-Lead MSOP
8-Lead SOIC_N
8-Lead SOIC_N
8-Lead SOIC_N
8-Lead SOIC_N
14-Lead SOIC_N
14-Lead SOIC_N
14-Lead SOIC_N
14-Lead TSSOP
14-Lead TSSOP
R-8
R-14
R-14
R-14
RU-14
RU-14
AD8618ARUZ-REEL
1 Z = RoHS Compliant Part.
Rev. G | Page 17 of 20
AD8615/AD8616/AD8618
NOTES
Data Sheet
Rev. G | Page 18 of 20
Data Sheet
NOTES
AD8615/AD8616/AD8618
Rev. G | Page 19 of 20
AD8615/AD8616/AD8618
NOTES
Data Sheet
©2004–2014 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D04648-0-6/14(G)
Rev. G | Page 20 of 20
相关型号:
AD8619ARUZ
Low Cost Micropower, Low Noise CMOS Rail-to- Rail, Input/Output Operational Amplifiers
ADI
AD8619ARUZ
QUAD OP-AMP, 2200 uV OFFSET-MAX, 0.35 MHz BAND WIDTH, PDSO14, ROHS COMPLIANT, MO-153AB-1, TSSOP-14
ROCHESTER
AD8619ARUZ-REEL
Low Cost Micropower, Low Noise CMOS Rail-to- Rail, Input/Output Operational Amplifiers
ADI
AD8619ARZ
Low Cost Micropower, Low Noise CMOS Rail-to- Rail, Input/Output Operational Amplifiers
ADI
AD8619ARZ
QUAD OP-AMP, 2200 uV OFFSET-MAX, 0.35 MHz BAND WIDTH, PDSO14, ROHS COMPLIANT, MS-012AB, SOIC-14
ROCHESTER
AD8619ARZ-REEL
Low Cost Micropower, Low Noise CMOS Rail-to- Rail, Input/Output Operational Amplifiers
ADI
AD8619ARZ-REEL7
Low Cost Micropower, Low Noise CMOS Rail-to- Rail, Input/Output Operational Amplifiers
ADI
AD8619WARUZ-RL
Low Cost Micropower, Low Noise CMOS Rail-to-Rail, Input/Output Operational Amplifiers
ADI
AD8619WARZ-R7
Low Cost Micropower, Low Noise CMOS Rail-to-Rail, Input/Output Operational Amplifiers
ADI
©2020 ICPDF网 联系我们和版权申明