AD ADA4851-4 Low cost, high speed, rail-to-rail, output op amp Datasheet

Low Cost, High Speed, Rail-to-Rail,
Output Op Amps
ADA4851-1/ADA4851-2/ADA4851-4
PIN CONFIGURATIONS
High speed
130 MHz, −3 dB bandwidth
375 V/μs slew rate
55 ns settling time to 0.1%
Excellent video specifications
0.1 dB flatness: 11 MHz
Differential gain: 0.08%
Differential phase: 0.09°
Fully specified at +3 V, +5 V, and ±5 V supplies
Rail-to-rail output
Output swings to within 60 mV of either rail
Low voltage offset: 0.6 mV
Wide supply range: 3 V to 10 V
Low power: 2.5 mA/amplifier
Power-down mode
Available in space-saving packages
6-lead SOT-23, 8-lead MSOP, and 14-lead TSSOP
ADA4851-1
6
+VS
–VS 2
5
POWER DOWN
+IN 3
4
–IN
VOUT 1
05143-001
FEATURES
TOP VIEW (Not to Scale)
Figure 1. ADA4851-1, 6-Lead SOT-23 (RJ-6)
ADA4851-2
8
+VS
–IN1 2
7
OUT
+IN1 3
6
–IN2
–VS 4
5
+IN2
05143-058
OUT1 1
TOP VIEW
(Not to Scale)
VOUT 1 1
14
VOUT 4
–IN 1 2
13
–IN 4
+IN 1
12
+IN 4
3
APPLICATIONS
Consumer video
Professional video
Video switchers
Active filters
Clock buffers
ADA4851-4
TOP VIEW
(Not to Scale)
11
–VS
+IN 2 5
10
+IN 3
–IN 2 6
9
–IN 3
VOUT 2 7
8
VOUT 3
+VS 4
05143-054
Figure 2. ADA4851-2, 8-Lead MSOP (RM-8)
Figure 3. ADA4851-4, 14-Lead TSSOP (RU-14)
GENERAL DESCRIPTION
With their combination of low price, excellent differential gain
(0.08%), differential phase (0.09º), and 0.1 dB flatness out to
11 MHz, these amplifiers are ideal for consumer video
applications.
4
G = +1
VS = 5V
RL = 1kΩ
CL = 5pF
3
2
1
0
–1
–2
–3
–4
–5
–6
1
10
100
FREQUENCY (MHz)
1k
05143-004
The ADA4851 family is designed to operate at supply voltages
as low as +3 V and up to ±5 V. These parts provide true singlesupply capability, allowing input signals to extend 200 mV
below the negative rail and to within 2.2 V of the positive rail.
On the output, the amplifiers can swing within 60 mV of either
supply rail.
The ADA4851 family is designed to work over the extended
temperature range (−40°C to +125°C).
CLOSED-LOOP GAIN (dB)
The ADA4851-1 (single)/ADA4851-2 (dual)/ADA4851-4
(quad) are low cost, high speed, voltage feedback rail-to-rail
output op amps. Despite their low price, these parts provide
excellent overall performance and versatility. The 130 MHz,
−3 dB bandwidth and high slew rate make these amplifiers well
suited for many general-purpose, high speed applications.
Figure 4. Small Signal Frequency Response
Rev. E
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 registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©2004–2007 Analog Devices, Inc. All rights reserved.
ADA4851-1/ADA4851-2/ADA4851-4
TABLE OF CONTENTS
Features .............................................................................................. 1
Thermal Resistance .......................................................................6
Applications....................................................................................... 1
ESD Caution...................................................................................6
Pin Configurations ........................................................................... 1
Typical Performance Characteristics ..............................................7
General Description ......................................................................... 1
Circuit Description......................................................................... 13
Revision History ............................................................................... 2
Headroom Considerations........................................................ 13
Specifications..................................................................................... 3
Overload Behavior and Recovery ............................................ 14
Specifications with +3 V Supply................................................. 3
Single-Supply Video Amplifier................................................. 15
Specifications with +5 V Supply................................................. 4
Video Reconstruction Filter...................................................... 15
Specifications with ±5 V Supply................................................. 5
Outline Dimensions ....................................................................... 16
Absolute Maximum Ratings............................................................ 6
Ordering Guide .......................................................................... 17
REVISION HISTORY
8/07—Rev. D to Rev. E
Changes to Applications .................................................................. 1
Changes to Common-Mode Rejection Ratio, Conditions.......... 5
Changes to Headroom Considerations Section ......................... 13
4/06—Rev. C to Rev. D
Added Video Reconstruction Filter Section ............................... 15
5/05—Rev. B to Rev. C
Changes to General Description .................................................... 1
Changes to Input Section............................................................... 14
4/05—Rev. A to Rev. B
Added ADA4851-2.............................................................Universal
Added 8-Lead MSOP .........................................................Universal
Changes to Features.......................................................................... 1
Changes to General Description .................................................... 1
Changes to Table 1............................................................................ 3
Changes to Table 2............................................................................ 4
Changes to Table 3............................................................................ 5
Changes to Table 4 and Figure 5..................................................... 6
Changes to Figure 12, Figure 15, and Figure 17 ........................... 8
Changes to Figure 18........................................................................ 9
Changes to Figure 28 Caption....................................................... 10
Changes to Figure 33...................................................................... 11
Changes to Figure 36 and Figure 38............................................. 12
Added Figure 39.............................................................................. 12
Changes to Circuit Description Section ...................................... 13
Changes to Headroom Considerations Section ......................... 13
Changes to Overload Behavior and Recovery Section .............. 14
Added Single-Supply Video Amplifier Section .......................... 15
Updated Outline Dimensions ....................................................... 16
Changes to Ordering Guide .......................................................... 17
1/05—Rev. 0 to Rev. A
Added ADA4851-4.............................................................Universal
Added 14-Lead TSSOP ......................................................Universal
Changes to Features ..........................................................................1
Changes to General Description .....................................................1
Changes to Figure 3...........................................................................1
Changes to Specifications.................................................................3
Changes to Figure 4...........................................................................6
Changes to Figure 8...........................................................................7
Changes to Figure 11.........................................................................8
Changes to Figure 22.........................................................................9
Changes to Figure 23, Figure 24, and Figure 25 ......................... 10
Changes to Figure 27 and Figure 28............................................. 10
Changes to Figure 29, Figure 30, and Figure 31 ......................... 11
Changes to Figure 34...................................................................... 11
Added Figure 37 ............................................................................. 12
Changes to Ordering Guide .......................................................... 15
Updated Outline Dimensions....................................................... 15
10/04—Revision 0: Initial Version
Rev. E | Page 2 of 20
ADA4851-1/ADA4851-2/ADA4851-4
SPECIFICATIONS
SPECIFICATIONS WITH +3 V SUPPLY
TA = 25°C, RF = 0 Ω for G = +1, RF = 1 kΩ for G > +1, RL = 1 kΩ, unless otherwise noted.
Table 1.
Parameter
DYNAMIC PERFORMANCE
−3 dB Bandwidth
Bandwidth for 0.1 dB Flatness
Slew Rate
Settling Time to 0.1%
NOISE/DISTORTION PERFORMANCE
Harmonic Distortion, HD2/HD3
Input Voltage Noise
Input Current Noise
Differential Gain
Differential Phase
Crosstalk (RTI)—ADA4851-2/ADA4851-4
DC PERFORMANCE
Input Offset Voltage
Input Offset Voltage Drift
Input Bias Current
Input Bias Current Drift
Input Bias Offset Current
Open-Loop Gain
INPUT CHARACTERISTICS
Input Resistance
Input Capacitance
Input Common-Mode Voltage Range
Input Overdrive Recovery Time (Rise/Fall)
Common-Mode Rejection Ratio
POWER-DOWN
Power-Down Input Voltage
Turn-Off Time
Turn-On Time
Power-Down Bias Current
Enabled
Power-Down
OUTPUT CHARACTERISTICS
Output Overdrive Recovery Time (Rise/Fall)
Output Voltage Swing
Short-Circuit Current
POWER SUPPLY
Operating Range
Quiescent Current per Amplifier
Quiescent Current (Power-Down)
Positive Power Supply Rejection
Negative Power Supply Rejection
Conditions
Min
Typ
G = +1, VO = 0.1 V p-p
G = +1, VO = 0.5 V p-p
G = +2, VO = 1 V p-p, RL = 150 Ω
G = +2, VO = 1 V p-p, RL = 150 Ω
G = +2, VO = 1 V step
G = +2, VO = 1 V step, RL = 150 Ω
104
80
130
105
40
15
100
50
MHz
MHz
MHz
MHz
V/μs
ns
fC = 1 MHz, VO = 1 V p-p, G = −1
f = 100 kHz
f = 100 kHz
G = +3, NTSC, RL = 150 Ω, VO = 2 V p-p
G = +3, NTSC, RL = 150 Ω, VO = 2 V p-p
f = 5 MHz, G = +2, VO = 1.0 V p-p
−73/−79
10
2.5
0.44
0.41
−70/−60
dBc
nV/√Hz
pA/√Hz
%
Degrees
dB
VO = 0.25 V to 0.75 V
80
0.6
4
2.3
6
20
105
−81
0.5/5.0
1.2
−0.2 to +0.8
60/60
−103
MΩ
pF
V
ns
dB
Power-down
Enabled
<1.1
>1.6
0.7
60
V
V
μs
ns
Power-down = 3 V
Power-down = 0 V
4
−14
Differential/common-mode
VIN = +3.5 V, −0.5 V, G = +1
VCM = 0 V to 0.5 V
VIN = +0.7 V, −0.1 V, G = +5
0.05 to 2.91
Sinking/sourcing
Rev. E | Page 3 of 20
−81
−80
3.3
4.0
6
−20
70/100
0.03 to 2.94
90/70
2.7
Power-down = low
+VS = +2.5 V to +3.5 V, −VS = −0.5 V
+VS = +2.5 V, −VS = −0.5 V to –1.5 V
Max
2.4
0.2
−100
−100
Unit
mV
μV/°C
μA
nA/°C
nA
dB
μA
μA
ns
V
mA
12
2.7
0.3
V
mA
mA
dB
dB
ADA4851-1/ADA4851-2/ADA4851-4
SPECIFICATIONS WITH +5 V SUPPLY
TA = 25°C, RF = 0 Ω for G = +1, RF = 1 kΩ for G > +1, RL = 1 kΩ, unless otherwise noted.
Table 2.
Parameter
DYNAMIC PERFORMANCE
−3 dB Bandwidth
Bandwidth for 0.1 dB Flatness
Slew Rate
Settling Time to 0.1%
NOISE/DISTORTION PERFORMANCE
Harmonic Distortion, HD2/HD3
Input Voltage Noise
Input Current Noise
Differential Gain
Differential Phase
Crosstalk (RTI)—ADA4851-2/ADA4851-4
DC PERFORMANCE
Input Offset Voltage
Input Offset Voltage Drift
Input Bias Current
Input Bias Current Drift
Input Bias Offset Current
Open-Loop Gain
INPUT CHARACTERISTICS
Input Resistance
Input Capacitance
Input Common-Mode Voltage Range
Input Overdrive Recovery Time (Rise/Fall)
Common-Mode Rejection Ratio
POWER-DOWN
Power-Down Input Voltage
Turn-Off Time
Turn-On Time
Power-Down Bias Current
Enabled
Power-Down
OUTPUT CHARACTERISTICS
Output Overdrive Recovery Time (Rise/Fall)
Output Voltage Swing
Short-Circuit Current
POWER SUPPLY
Operating Range
Quiescent Current per Amplifier
Quiescent Current (Power-Down)
Positive Power Supply Rejection
Negative Power Supply Rejection
Conditions
Min
Typ
G = +1, VO = 0.1 V p-p
G = +1, VO = 0.5 V p-p
G = +2, VO = 1.4 V p-p, RL = 150 Ω
G = +2, VO = 1.4 V p-p, RL = 150 Ω
G = +2, VO = 2 V step
G = +2, VO = 2 V step, RL = 150 Ω
96
72
125
96
35
11
200
55
MHz
MHz
MHz
MHz
V/μs
ns
fC = 1 MHz, VO = 2 V p-p, G = +1
f = 100 kHz
f = 100 kHz
G = +2, NTSC, RL = 150 Ω, VO = 2 V p-p
G = +2, NTSC, RL = 150 Ω, VO = 2 V p-p
f = 5 MHz, G = +2, VO = 2.0 V p-p
−80/−100
10
2.5
0.08
0.11
−70/−60
dBc
nV/√Hz
pA/√Hz
%
Degrees
dB
VO = 1 V to 4 V
97
0.6
4
2.2
6
20
107
−86
0.5/5.0
1.2
−0.2 to +2.8
50/45
−105
MΩ
pF
V
ns
dB
Power-down
Enabled
<1.1
>1.6
0.7
50
V
V
μs
ns
Power-down = 5 V
Power-down = 0 V
33
−22
Differential/common-mode
VIN = +5.5 V, −0.5 V, G = +1
VCM = 0 V to 2 V
VIN = +1.1 V, −0.1 V, G = +5
0.09 to 4.91
Sinking/sourcing
Rev. E | Page 4 of 20
−82
−81
3.4
3.9
40
−30
60/70
0.06 to 4.94
110/90
2.7
Power-down = low
+VS = +5 V to +6 V, −VS = 0 V
+VS = +5 V, −VS = −0 V to −1 V
Max
2.5
0.2
−101
−101
Unit
mV
μV/°C
μA
nA/°C
nA
dB
μA
μA
ns
V
mA
12
2.8
0.3
V
mA
mA
dB
dB
ADA4851-1/ADA4851-2/ADA4851-4
SPECIFICATIONS WITH ±5 V SUPPLY
TA = 25°C, RF = 0 Ω for G = +1, RF = 1 kΩ for G > +1, RL = 1 kΩ, unless otherwise noted.
Table 3.
Parameter
DYNAMIC PERFORMANCE
−3 dB Bandwidth
Bandwidth for 0.1 dB Flatness
Slew Rate
Settling Time to 0.1%
NOISE/DISTORTION PERFORMANCE
Harmonic Distortion, HD2/HD3
Input Voltage Noise
Input Current Noise
Differential Gain
Differential Phase
Crosstalk (RTI)—ADA4851-2/ADA4851-4
DC PERFORMANCE
Input Offset Voltage
Input Offset Voltage Drift
Input Bias Current
Input Bias Current Drift
Input Bias Offset Current
Open-Loop Gain
INPUT CHARACTERISTICS
Input Resistance
Input Capacitance
Input Common-Mode Voltage Range
Input Overdrive Recovery Time (Rise/Fall)
Common-Mode Rejection Ratio
POWER-DOWN
Power-Down Input Voltage
Turn-Off Time
Turn-On Time
Power-Down Bias Current
Enabled
Power-Down
OUTPUT CHARACTERISTICS
Output Overdrive Recovery Time (Rise/Fall)
Output Voltage Swing
Short-Circuit Current
POWER SUPPLY
Operating Range
Quiescent Current per Amplifier
Quiescent Current (Power-Down)
Positive Power Supply Rejection
Negative Power Supply Rejection
Conditions
Min
Typ
G = +1, VO = 0.1 V p-p
G = +1, VO = 1 V p-p
G = +2, VO = 2 V p-p, RL = 150 Ω
G = +2, VO = 2 V p-p, RL = 150 Ω
G = +2, VO = 7 V step
G = +2, VO = 2 V step
G = +2, VO = 2 V step, RL = 150 Ω
83
52
105
74
40
11
375
190
55
MHz
MHz
MHz
MHz
V/μs
V/μs
ns
fC = 1 MHz, VO = 2 V p-p, G = +1
f = 100 kHz
f = 100 kHz
G = +2, NTSC, RL = 150 Ω, VO = 2 V p-p
G = +2, NTSC, RL = 150 Ω, VO = 2 V p-p
f = 5 MHz, G = +2, VO = 2.0 V p-p
−83/−107
10
2.5
0.08
0.09
−70/−60
dBc
nV/√Hz
pA/√Hz
%
Degrees
dB
VO = ±2.5 V
99
0.6
4
2.2
6
20
106
−90
0.5/5.0
1.2
−5.2 to +2.8
50/25
−105
MΩ
pF
V
ns
dB
Power-down
Enabled
< −3.9
> −3.4
0.7
30
V
V
μs
ns
Power-down = +5 V
Power-down = −5 V
100
−50
Differential/common-mode
VIN = ±6 V, G = +1
VCM = 0 V to −4 V
VIN = ±1.2 V, G = +5
−4.87 to +4.88
Sinking/sourcing
Rev. E | Page 5 of 20
−82
−81
3.5
4.0
130
−60
80/50
−4.92 to +4.92
125/110
2.7
Power-down = low
+VS = +5 V to +6 V, −VS = −5 V
+VS = +5 V, −VS = −5 V to −6 V
Max
2.9
0.2
−101
−102
Unit
mV
μV/°C
μA
nA/°C
nA
dB
μA
μA
ns
V
mA
12
3.2
0.3
V
mA
mA
dB
dB
ADA4851-1/ADA4851-2/ADA4851-4
ABSOLUTE MAXIMUM RATINGS
PD = Quiescent Power + (Total Drive Power − Load Power)
Table 4.
Parameter
Supply Voltage
Power Dissipation
Common-Mode Input Voltage
Differential Input Voltage
Storage Temperature Range
Operating Temperature Range
Lead Temperature
Junction Temperature
⎛V V
⎞ V 2
PD = (VS × I S ) + ⎜ S × OUT ⎟ – OUT
RL ⎠
RL
⎝ 2
Rating
12.6 V
See Figure 5
−VS − 0.5 V to +VS + 0.5 V
+VS to −VS
−65°C to +125°C
−40°C to +125°C
JEDEC J-STD-20
150°C
RMS output voltages should be considered. If RL is referenced
to −VS, as in single-supply operation, the total drive power is
VS × IOUT. If the rms signal levels are indeterminate, consider the
worst case, when VOUT = VS/4 for RL to midsupply.
PD = (VS × I S ) +
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.
THERMAL RESISTANCE
θJA is specified for the worst-case conditions, that is, θJA is specified
for device soldered in circuit board for surface-mount packages.
(VS / 4 )2
RL
In single-supply operation with RL referenced to −VS, worst case
is VOUT = VS/2.
Airflow increases heat dissipation, effectively reducing θJA.
In addition, more metal directly in contact with the package
leads and through holes under the device reduces θJA.
Figure 5 shows the maximum safe power dissipation in the
package vs. the ambient temperature for the 6-lead SOT-23
(170°C/W), the 8-lead MSOP (150°C/W), and the 14-lead
TSSOP (120°C/W) on a JEDEC standard 4-layer board. θJA
values are approximations.
2.0
θJA
170
150
120
Unit
°C/W
°C/W
°C/W
Maximum Power Dissipation
The maximum safe power dissipation for the ADA4851-1/
ADA4851-2/ADA4851-4 is limited by the associated rise in
junction temperature (TJ) on the die. At approximately 150°C,
which is the glass transition temperature, the plastic changes its
properties. Even temporarily exceeding this temperature limit
may change the stresses that the package exerts on the die,
permanently shifting the parametric performance of the
amplifiers. Exceeding a junction temperature of 150°C for an
extended period can result in changes in silicon devices,
potentially causing degradation or loss of functionality.
TSSOP
1.5
MSOP
1.0
SOT-23-6
0.5
0
–55 –45 –35 –25 –15 –5
5
15 25 35 45 55 65 75 85 95 105 115 125
AMBIENT TEMPERATURE (°C)
05143-057
Package Type
6-lead SOT-23
8-lead MSOP
14-lead TSSOP
MAXIMUM POWER DISSIPATION (W)
Table 5. Thermal Resistance
Figure 5. Maximum Power Dissipation vs. Temperature for a 4-Layer Board
ESD CAUTION
The power dissipated in the package (PD) is the sum of the
quiescent power dissipation and the power dissipated in the die
due to the drive of the amplifier at the output. The quiescent
power is the voltage between the supply pins (VS) times the
quiescent current (IS).
Rev. E | Page 6 of 20
ADA4851-1/ADA4851-2/ADA4851-4
TYPICAL PERFORMANCE CHARACTERISTICS
TA = 25°C, RF = 0 Ω for G = +1, RF = 1 kΩ for G > +1, RL = 1 kΩ, unless otherwise noted.
1
0
2
G = –1
–1
–2
–3
G = +10
–4
G = +2
–5
10pF
G = +1
VS = 5V
RL = 1kΩ
VOUT = 0.1V p-p
3
CLOSED-LOOP GAIN (dB)
CLOSED-LOOP GAIN (dB)
4
VS = ±5V
RL = 150Ω
VOUT = 0.1V p-p
1
0
5pF
–1
0pF
–2
–3
–4
–6
10
100
FREQUENCY (MHz)
–6
05143-006
1
Figure 6. Small Signal Frequency Response for Various Gains
1
10
100
Figure 9. Small Signal Frequency Response for Various Capacitor Loads
1
1
+125°C
RL = 150Ω
0
VS = ±5V
G = +1
VOUT = 0.1V p-p
–1
CLOSED-LOOP GAIN (dB)
RL = 1kΩ
–2
–3
–4
+25°C
–2
–3
–4
10
100
300
–6
05143-009
1
1
10
100
Figure 7. Small Signal Frequency Response for Various Loads
Figure 10. Small Signal Frequency Response for Various Temperatures
1
2
G = +1
RL = 150Ω
VOUT = 0.1V p-p
1
VS = +5V
VS = ±5V
RL = 150Ω
VOUT = 1V p-p
0
CLOSED-LOOP GAIN (dB)
0
–1
300
FREQUENCY (MHz)
05143-008
–5
FREQUENCY (MHz)
VS = ±5V
–2
–3
–4
–1
–2
–3
–4
G = +2
G = +10
–5
G = –1
–6
–5
1
10
100
300
FREQUENCY (MHz)
05143-007
CLOSED-LOOP GAIN (dB)
VS = ±5V
G = +1
VOUT = 0.1V p-p
–1
–5
–6
+85°C
–40°C
Figure 8. Small Signal Frequency Response for Various Supplies
–7
1
10
100
FREQUENCY (MHz)
Figure 11. Large Signal Frequency Response for Various Gains
Rev. E | Page 7 of 20
05143-012
CLOSED-LOOP GAIN (dB)
0
–6
300
FREQUENCY (MHz)
05143-010
–5
–7
ADA4851-1/ADA4851-2/ADA4851-4
6.2
6.1
G = –1
VS = 3V
RL = 150Ω
VOUT = 2V
–50
6.0
HD2
–60
5.9
DISTORTION (dBc)
VOUT = 100mV p-p
5.8
VOUT = 1V p-p
VOUT = 2V p-p
5.7
–70
–80
HD3
–90
5.6
1
10
100
FREQUENCY (MHz)
–110
0.1
05143-021
5.4
0.1
Figure 15. Harmonic Distortion vs. Frequency
Figure 12. 0.1 dB Flatness Response
–50
1
VS = ±5V
G = +1
VOUT = 1V p-p
–1
RL = 1kΩ
–2
G = +2
VS = ±5V
RL = 1kΩ
f = 2MHz
–60
HARMONIC DISTORTION (dBc)
RL = 150Ω
–3
–4
–80
HD3
–90
–100
–110
–5
10
100
300
–120
05143-015
1
FREQUENCY (MHz)
0
0
–30
60
–120
40
–150
GAIN
20
–180
0
–210
–20
10
100
1k
10k
100k
1M
10M
100M
FREQUENCY (Hz)
–240
1G
HARMONIC DISTORTION (dBc)
–90
OPEN-LOOP PHASE (Degrees)
80
–50
4
5
6
7
8
9
10
G = +1
VOUT = 2V p-p
VS = ±5V
–60
RL = 1kΩ HD2
–70
–80
RL = 150Ω HD2
RL = 150Ω HD3
–90
RL = 1kΩ HD3
–100
05143-029
–60
PHASE
3
–40
VS = ±5V
100
2
Figure 16. Harmonic Distortion vs. Output Voltage
140
120
1
OUTPUT AMPLITUDE (V p-p)
Figure 13. Large Frequency Response for Various Loads
OPEN-LOOP GAIN (dB)
HD2
–70
05143-017
CLOSED-LOOP GAIN (dB)
0
–6
10
1
FREQUENCY (MHz)
05143-014
–100
5.5
–110
0.1
1
10
FREQUENCY (MHz)
Figure 17. Harmonic Distortion vs. Frequency for Various Loads
Figure 14. Open-Loop Gain and Phase vs. Frequency
Rev. E | Page 8 of 20
05143-016
CLOSED-LOOP GAIN (dB)
–40
VS = ±5V
G = +2
RL = 150Ω
RF = 1kΩ
ADA4851-1/ADA4851-2/ADA4851-4
OUTPUT VOLTAGE FOR ±5V SUPPLY (V)
–60
RL = 1kΩ HD2
–70
–80
RL = 150Ω HD2
RL = 150Ω HD3
–90
–100
RL = 1kΩ HD3
2.550
0.025
2.525
0
2.500
–0.025
1
10
FREQUENCY (MHz)
4
5 × INPUT
50
100
2.425
200
150
Figure 21. Small Signal Transient Response for Various Supplies
2.575
2
1
0
–1
–2
10pF
G = +1
VS = 5V
RL = 150Ω
2.550
OUTPUT VOLTAGE (V)
3
0
TIME (ns)
G = +5
VS = ±5V
RL = 150Ω
f = 1MHz
OUTPUT
5
2.475
2.450
–0.050
Figure 18. Harmonic Distortion vs. Frequency for Various Loads
6
VS = ±5V
VS = +5V
–0.075
–110
0.1
INPUT AND OUTPUT VOLTAGE (V)
0.050
05143-013
HARMONIC DISTORTION (dBc)
–50
2.575
G = +1 OR +2
RL = 1kΩ
OUTPUT VOLTAGE FOR 5V SUPPLY (V)
0.075
G = +1
VOUT = 2V p-p
VS = 5V
05143-024
–40
0pF
2.525
2.500
2.475
–3
2.450
–4
200
300
400
500
600
700
800
900
1k
TIME (ns)
2.425
OUTPUT VOLTAGE FOR ±5V SUPPLY (V)
4
3
OUTPUT
2
1
0
–1
–2
–3
–4
–5
–6
0
100
200
300
400
500
600
700
800
TIME (ns)
60
80
100
120
140
160
1.5
G = +1
VS = ±5V
RL = 150Ω
f = 1MHz
INPUT
40
180
200
Figure 22. Small Signal Transient Response for Capacitive Load
900
1k
05143-022
INPUT AND OUTPUT VOLTAGE (V)
5
20
TIME (ns)
Figure 19. Output Overdrive Recovery
6
0
Figure 20. Input Overdrive Recovery
3.0
G = +2
RL = 150Ω
1.0
2.5
VS = ±5V
VS = +5V
0.5
2.0
0
1.5
–0.5
1.0
–1.0
0.5
–1.5
0
50
100
150
0
200
TIME (ns)
Figure 23. Large Signal Transient Response for Various Supplies
Rev. E | Page 9 of 20
OUTPUT VOLTAGE FOR 5V SUPPLY (V)
100
05143-028
0
05143-019
–6
05143-026
–5
ADA4851-1/ADA4851-2/ADA4851-4
VS = +5V
2.0
0
1.5
–0.5
1.0
–1.0
0.5
0
50
100
0
200
150
TIME (ns)
VDISABLE
4
3
2
1
0
VOUT
–1
0
15
3.5
0.5
3.0
+VS – VOUT
VS = ±5V
SUPPLY CURRENT (mA)
0.4
VS = ±5V
VS = +3V
0.3
–VS – VOUT
0.2
2.5
VS = +5V
2.0
VS = +3V
1.5
1.0
0.1
0
5
10
15
20
25
30
35
LOAD CURRENT (mA)
0
–5
0
1
2
3
4
5
INPUT OFFSET VOLTAGE (μV)
200
300
POSITIVE SLEW RATE
200
100
VS = +3V
100
VS = ±5V
0
VS = +5V
–100
–200
–300
0
1
2
3
4
5
6
7
8
OUTPUT VOLTAGE STEP (V p-p)
9
10
05143-032
0
–1
300
NEGATIVE SLEW RATE
400
–2
Figure 28. ADA4851-1, Supply Current vs. POWER DOWN Pin Voltage
G = +2
VS = ±5V
RL = 1kΩ
25% TO 75% OF VO
500
–3
DISABLE VOLTAGE (V)
Figure 25. Output Saturation Voltage vs. Load Current
600
–4
–400
–40
–25
–10
5
20
35
50
65
80
95
110
125
TEMPERATURE (°C)
Figure 29. Input Offset Voltage vs. Temperature for Various Supplies
Figure 26. Slew Rate vs. Output Voltage
Rev. E | Page 10 of 20
05143-035
0
05143-034
0.5
05143-049
DC VOLTAGE DIFFERENTIAL FROM VS (V)
45
Figure 27. Enable/Disable Time
Figure 24. Large Signal Transient Response for Various Supplies
SLEW RATE (V/μs)
30
TIME (μs)
05143-033
VS = ±5V
0.5
G = +2
VS = 5V
fIN = 400kHz
5
VOLTAGE (V)
2.5
OUTPUT VOLTAGE FOR 5V SUPPLY (V)
1.0
–1.5
6
3.0
G = +1
RL = 150Ω
05143-027
OUTPUT VOLTAGE FOR ±5V SUPPLY (V)
1.5
ADA4851-1/ADA4851-2/ADA4851-4
2.2
1000
G = +1
IB+, VS = ±5V
1.8
IB–, VS = ±5V
IB+, VS = +5V
1.6
IB–, VS = +5V
1.2
–40
–25
–10
5
20
35
50
65
80
95
110
125
TEMPERATURE (°C)
10
1
10
05143-036
1.4
100
100
100k
1M
10M
100M
Figure 33. Voltage Noise vs. Frequency
0.09
100
G = +2
VS = ±5V
CURRENT NOISE (pA/ Hz)
0.08
+VS – VOUT
VS = +5V
0.07
+VS – VOUT
–VS – VOUT
0.06
10
0.05
–25
–10
5
20
35
50
65
80
95
110
125
TEMPERATURE (°C)
1
10
100
10k
100k
1M
10M
100M
FREQUENCY (Hz)
Figure 31. Output Saturation vs. Temperature for Various Supplies
Figure 34. Current Noise vs. Frequency
3.2
80
VS = ±5V
VS = ±5V
N = 420
x = –260μV
σ = 780μV
70
3.0
60
2.8
COUNT
50
VS = +5V
2.6
40
30
2.4
VS = +3V
20
2.2
10
–25
–10
5
20
35
50
65
80
95
110
125
TEMPERATURE (°C)
05143-038
2.0
–40
1k
0
–4
–3
–2
–1
0
1
2
3
VOFFSET (mV)
Figure 35. Input Offset Voltage Distribution
Figure 32. Supply Current vs. Temperature for Various Supplies
Rev. E | Page 11 of 20
4
05143-047
0.04
–40
05143-045
–VS – VOUT
05143-037
DC VOLTAGE DIFFERENTIAL FROM VS (V)
10k
FREQUENCY (Hz)
Figure 30. Input Bias Current vs. Temperature for Various Supplies
SUPPLY CURRENT (mA)
1k
05143-044
VOLTAGE NOISE (nV/ Hz)
INPUT BIAS CURRENT (μA)
2.0
ADA4851-1/ADA4851-2/ADA4851-4
0
–30
VS = ±5V
–20
–50
DRIVE AMPS 1, 2, AND 4
LISTEN AMP 3
–30
–60
–70
–80
–90
–40
–50
–60
DRIVE AMP 1
LISTEN AMP 2
–70
–100
–80
–110
1k
10k
100k
1M
10M
100M
1G
FREQUENCY (Hz)
1
100
Figure 38. ADA4851-4, RTI Crosstalk vs. Frequency
Figure 36. Common-Mode Rejection Ratio (CMRR) vs. Frequency
0
0
VS = ±5V
–10
–20
–20
–30
+PSR
–50
–60
–30
CROSSTALK (dB)
–40
–PSR
–70
–40
–50
–60
–70
–90
–80
–100
–90
1k
10k
100k
1M
10M
100M
FREQUENCY (Hz)
1G
05143-023
–80
–110
100
G = +2
VS = 5V
RL = 1kΩ
VIN = 1V p-p
–100
0.1
DRIVE AMP 1
LISTEN AMP 2
DRIVE AMP 2
LISTEN AMP 1
1
10
100
FREQUENCY (MHz)
Figure 39. ADA4851-2, RTI Crosstalk vs. Frequency
Figure 37. Power Supply Rejection (PSR) vs. Frequency
Rev. E | Page 12 of 20
05143-060
–10
POWER SUPPLY REJECTION (dB)
10
FREQUENCY (MHz)
05143-055
–90
–100
0.1
05143-020
–120
G = +2
VS = 5V
RL = 1kΩ
VIN = 1V p-p
–10
CROSSTALK (dB)
COMMON-MODE REJECTION (dB)
–40
ADA4851-1/ADA4851-2/ADA4851-4
CIRCUIT DESCRIPTION
460
480
500
540
These amplifiers are designed for use in low voltage systems.
To obtain optimum performance, it is useful to understand the
behavior of the amplifiers as input and output signals approach
the headroom limits of the amplifiers. The input common-mode
voltage range of the amplifiers extends from the negative supply
voltage (actually 200 mV below this), or from ground for singlesupply operation, to within 2.2 V of the positive supply voltage.
Therefore, at a gain of 3, the amplifiers can provide full rail-torail output swing for supply voltages as low as 3.3 V and down
to 3 V for a gain of 4.
580
600
–6
–5
–4
–3
–2
–1
0
1
2
4
05143-046
The input stage is the headroom limit for signals approaching
the positive rail. Figure 40 shows a typical offset voltage vs. the
input common-mode voltage for the ADA4851-1/ADA4851-2/
ADA4851-4 amplifiers on a ±5 V supply. Accurate dc performance
is maintained from approximately 200 mV below the negative
supply to within 2.2 V of the positive supply. For high speed
signals, however, there are other considerations. Figure 41
shows −3 dB bandwidth vs. input common-mode voltage for a
unity-gain follower. As the common-mode voltage gets within 2
V of positive supply, the amplifier responds well but the
bandwidth begins to drop as the common-mode voltage
approaches the positive supply. This can manifest itself in
increased distortion or settling time. Higher frequency signals
require more headroom than the lower frequencies to maintain
distortion performance.
560
1000
3
VCM (V)
Figure 40. VOS vs. Common-Mode Voltage, VS = ±5 V
2
1
G = +1
RL = 1kΩ
VS = 5V
VCM = 3.0V
0
VCM = 3.1V
–1
GAIN (dB)
Exceeding the headroom limit is not a concern for any inverting
gain on any supply voltage, as long as the reference voltage at
the positive input of the amplifier lies within the input commonmode range of the amplifier.
520
05143-050
HEADROOM CONSIDERATIONS
440
VOS (μV)
The ADA4851-1/ADA4851-2/ADA4851-4 feature a high slew
rate input stage that is a true single-supply topology, capable of
sensing signals at or below the minus supply rail. The rail-to-rail
output stage can pull within 60 mV of either supply rail when
driving light loads and within 0.17 V when driving 150 Ω. High
speed performance is maintained at supply voltages as low as 2.7 V.
Rev. E | Page 13 of 20
–2
VCM = 3.2V
–3
VCM = 3.3V
–4
–5
–6
0.1
1
10
100
FREQUENCY (MHz)
Figure 41. Unity-Gain Follower Bandwidth vs. Input Common-Mode
ADA4851-1/ADA4851-2/ADA4851-4
Figure 42 illustrates how the rising edge settling time for the
amplifier is configured as a unity-gain follower, stretching out
as the top of a 1 V step input that approaches and exceeds the
specified input common-mode voltage limit.
The amplifiers do not exhibit phase reversal, even for input
voltages beyond the voltage supply rails. Going more than 0.6 V
beyond the power supplies turns on protection diodes at the input
stage, which greatly increases the current draw of the devices.
3.6
3.50
G = +1
RL = 1kΩ
VS = 5V
3.4
G = +1
RL = 1kΩ
VS = 5V
3.25
OUTPUT VOLTAGE (V)
For signals approaching the negative supply and inverting gain
and high positive gain configurations, the headroom limit is the
output stage. The ADA4851-1/ADA4851-2/ADA4851-4 amplifiers
use a common emitter output stage. This output stage maximizes
the available output range, limited by the saturation voltage of
the output transistors. The saturation voltage increases with the
drive current that the output transistor is required to supply due
to the collector resistance of the output transistor.
VSTEP = 2.25V TO 3.25V
3.00
VSTEP = 2.25V TO
3.5V, 4V, AND 5V
2.75
2.50
2.25
0
100
200
300
400
VSTEP = 2V TO 3V
2.8
VSTEP = 2.2V TO 3.2V
2.4
VSTEP = 2.4V TO 3.4V
1.8
10
20
30
40
50
60
70
80
90
100
TIME (ns)
05143-052
2.0
0
700
800
900
1k
Output
VSTEP = 2.3V TO 3.3V
2.2
600
Figure 43. Pulse Response of G = +1 Follower,
Input Step Overloading the Input Stage
VSTEP = 2.1V TO 3.1V
2.6
500
TIME (ns)
05143-051
2.00
3.0
Output overload recovery is typically within 35 ns after the
input of the amplifier is brought to a nonoverloading value.
Figure 44 shows output recovery transients for the amplifier
configured in an inverting gain of 1 recovering from a saturated
output from the top and bottom supplies to a point at midsupply.
Figure 42. Output Rising Edge for 1 V Step at Input Headroom Limits
7
OVERLOAD BEHAVIOR AND RECOVERY
Input
The specified input common-mode voltage of the ADA4851-1/
ADA4851-2/ADA4851-4 is 200 mV below the negative supply
to within 2.2 V of the positive supply. Exceeding the top limit
results in lower bandwidth and increased rise time, as seen in
Figure 41 and Figure 42. Pushing the input voltage of a unitygain follower to less than 2 V from the positive supply leads to
the behavior shown in Figure 43—an increasing amount of output
error as well as a much increased settling time. The recovery time
from input voltages 2.2 V or closer to the positive supply is
approximately 55 ns, which is limited by the settling artifacts
caused by transistors in the input stage coming out of saturation.
6
INPUT AND OUTPUT VOLTAGE (V)
As the saturation point of the output stage is approached, the
output signal shows increasing amounts of compression and
clipping. As in the input headroom case, higher frequency
signals require a bit more headroom than the lower frequency
signals. Figure 16 illustrates this point by plotting the typical
distortion vs. the output amplitude.
Rev. E | Page 14 of 20
G = –1
RL = 1kΩ
VS = 5V
VOUT = 5V TO 2.5V
5
VOUT = 0V TO 2.5V
4
3
INPUT
VOLTAGE
EDGES
2
1
0
–1
–2
0
10
20
30
40
50
60
70
TIME (ns)
Figure 44. Overload Recovery
80
90
100
05143-053
OUTPUT VOLTAGE (V)
3.2
ADA4851-1/ADA4851-2/ADA4851-4
SINGLE-SUPPLY VIDEO AMPLIFIER
The ADA4851 family of amplifiers is well suited for portable
video applications. When operating in low voltage single-supply
applications, the input signal is limited by the input stage
headroom. For additional information, see the Headroom
Considerations section. Table 6 illustrates the effects of supply
voltage, input signal, various gains, and output signal swing for
the typical video amplifier shown in Figure 45.
RF
+VS
An example of an 8 MHz, 3-pole, Sallen-Key, low-pass, video
reconstruction filter is shown in Figure 46. This circuit features
a gain of 3, has a 0.1 dB bandwidth of 8.2 MHz, and over 17 dB
attenuation at 27 MHz (see Figure 47). The filter has three poles;
two are active with a third passive pole (R6 and C4) placed at the
output. C3 improves the filter roll-off. R6, R7, and R8 comprise
the video load of 150 Ω. Components R6, C4, R7, R8, and the
input termination of the network analyzer form a 12.8 dB
attenuator; therefore, the reference level is roughly −3.3 dB,
as shown in Figure 47.
C1
2.2μF
C2
51pF
+
R2
R3
47Ω 125Ω
IOUT
U1
75Ω CABLE
75Ω
V′
VIN
VIDEO DAC
VOUT
75Ω
R1
37.4Ω
+3V
R6
6.8Ω
C1
51pF
R5
1kΩ
R8
75Ω
C4
1nF
R4
2kΩ
Figure 45. Video Amplifier
R7
68.1Ω
C3
6.8pF
Table 6. Recommended Values
Supply
Voltage
(V)
3
3
5
Input
Range
(V)
0 to 0.8
0 to 0.8
0 to 2.8
Figure 46. 8 MHz Video Reconstruction Filter Schematic
RG
(kΩ)
1
0.499
1
RF
(kΩ)
1
1
1
Gain
(V/V)
2
3
2
V’
(V)
1.6
2.4
4.9
5dB/REF –15dB
VOUT
(V)
0.8
1.2
2.45
1: –3.3931dB
8.239 626MHz
1
VIDEO RECONSTRUCTION FILTER
Rev. E | Page 15 of 20
0.03
0.1
1
FREQUENCY (MHz)
10
05143-062
At higher frequencies, active filters require wider bandwidths to
work properly. Excessive phase shift introduced by lower frequency
op amps can significantly affect the filter performance.
A common application for active filters is at the output of video
DACs/encoders. The filter, or more appropriately, the video
reconstruction filter is used at the output of a video DAC/
encoder to eliminate the multiple images that are created
during the sampling process within the DAC. For portable
video applications, the ADA4851-x is an ideal choice due to
its lower power requirements and high performance.
VOUT
05143-061
C2
0.01μF
05143-059
PD
RG
100
Figure 47. Video Reconstruction Filter Frequency Performance
ADA4851-1/ADA4851-2/ADA4851-4
OUTLINE DIMENSIONS
2.90 BSC
6
5
4
1
2
3
2.80 BSC
1.60 BSC
PIN 1
INDICATOR
0.95 BSC
1.90
BSC
1.30
1.15
0.90
1.45 MAX
0.50
0.30
0.15 MAX
0.22
0.08
10°
4°
0°
SEATING
PLANE
0.60
0.45
0.30
COMPLIANT TO JEDEC STANDARDS MO-178-AB
Figure 48. 6-Lead Small Outline Transistor Package [SOT-23]
(RJ-6)
Dimensions shown in millimeters
3.20
3.00
2.80
8
3.20
3.00
2.80
1
5
5.15
4.90
4.65
4
PIN 1
0.65 BSC
0.95
0.85
0.75
1.10 MAX
0.15
0.00
0.38
0.22
COPLANARITY
0.10
0.23
0.08
8°
0°
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 49. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
Rev. E | Page 16 of 20
0.80
0.60
0.40
ADA4851-1/ADA4851-2/ADA4851-4
5.10
5.00
4.90
14
8
4.50
4.40
4.30
6.40
BSC
1
7
PIN 1
1.05
1.00
0.80
0.65
BSC
1.20
MAX
0.15
0.05
0.30
0.19
0.20
0.09
SEATING
COPLANARITY
PLANE
0.10
8°
0°
0.75
0.60
0.45
COMPLIANT TO JEDEC STANDARDS MO-153-AB-1
Figure 50. 14-Lead Thin Shrink Small Outline Package [TSSOP]
(RU-14)
Dimensions shown in millimeters
ORDERING GUIDE
Model
ADA4851-1YRJZ-R2 1
ADA4851-1YRJZ-RL1
ADA4851-1YRJZ-RL71
ADA4851-2YRMZ1
ADA4851-2YRMZ-RL1
ADA4851-2YRMZ-RL71
ADA4851-4YRUZ1
ADA4851-4YRUZ-RL1
ADA4851-4YRUZ-R71
1
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
Package Description
6-Lead Small Outline Transistor Package (SOT-23)
6-Lead Small Outline Transistor Package (SOT-23)
6-Lead Small Outline Transistor Package (SOT-23)
8-Lead Mini Small Outline Package (MSOP)
8-Lead Mini Small Outline Package (MSOP)
8-Lead Mini Small Outline Package (MSOP)
14-Lead Thin Shrink Small Outline Package (TSSOP)
14-Lead Thin Shrink Small Outline Package (TSSOP)
14-Lead Thin Shrink Small Outline Package (TSSOP)
Z = RoHS Compliant Part.
Rev. E | Page 17 of 20
Package Option
RJ-6
RJ-6
RJ-6
RM-8
RM-8
RM-8
RU-14
RU-14
RU-14
Branding
HHB
HHB
HHB
HSB
HSB
HSB
ADA4851-1/ADA4851-2/ADA4851-4
NOTES
Rev. E | Page 18 of 20
ADA4851-1/ADA4851-2/ADA4851-4
NOTES
Rev. E | Page 19 of 20
ADA4851-1/ADA4851-2/ADA4851-4
NOTES
© 2004–2007 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D05143-0-8/07(E)
Rev. E | Page 20 of 20
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