ANALOG DEVICES ADA4859-3 Service Manual
Single-Supply, Fixed G = 2, High Speed,
www.BDTIC.com/ADI
FEATURES
Integrated charge pump
Supply range: 3 V to 5.5 V
Output range: −3.3 V to −1.8 V
50 mA maximum output current at −3 V for external use
High speed amplifiers
−3 dB bandwidth: 195 MHz
Slew rate: 740 V/μs
0.1 dB gain flatness: 60 MHz
0.1% settling time: 20 ns
Low power
Total quiescent current: 38 mA
Power-down feature
High input common-mode voltage range
−1.8 V to +3.8 V at +5 V supply
Current feedback architecture
Differential gain error: 0.01%
Differential phase error: 0.02°
Available in 16-lead LFCSP
APPLICATIONS
Professional video
Consumer video
Imaging
Active filters
Video Amplifier with Charge Pump
ADA4859-3
CONNECTION DIAGRAM
ADA4859-3
OUT1
–IN1
+IN1
NC
16 15 14 13
12
+V
1
S
2C1_a
CHARGE
PUMP
3
C1_b
CPO
4
5678
S
+V
NOTES
1. NC = NO CONNECT .
2. EXPOSED PAD, CONNECT T O GROUND.
+IN3
Figure 1.
–IN3
OUT3
+IN2
–IN2
11
OUT2
10
PD
9
07715-001
GENERAL DESCRIPTION
The ADA4859-3 (triple) is a single-supply, high speed current
feedback amplifier with an integrated charge pump that eliminates
the need for negative supplies in order to output negative voltages
or output a 0 V level for video applications. The 195 MHz, large
signal −3 dB bandwidth at a fixed gain of 2, as well as the 740 V/μs
slew rate, make this amplifier ideal for high resolution professional
and consumer video applications. The amplifier also has a wide
input common-mode voltage range that extends from 1.8 V
below ground to 1.2 V below the positive rail at 5 V supply.
Rev. 0
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.
This triple video amplifier is designed to operate on supply
voltages of 3.3 V to 5 V, using only 38 mA total quiescent
current, including the charge pump. To further reduce the
power consumption, it is equipped with a power-down feature
that lowers the total supply current to as low as 2 mA when the
amplifier is not being used. Even in power-down mode, the
charge pump can be used to power external components. The
maximum output current for external use is 50 mA at −3 V.
The ADA4858-3 is available in a 16-lead LFCSP, and it is designed
to work over the industrial temperature range of −40°C to +105°C.
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 ©2008 Analog Devices, Inc. All rights reserved.
ADA4859-3
www.BDTIC.com/ADI
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Connection Diagram ....................................................................... 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 5
Maximum Power Dissipation ..................................................... 5
ESD Caution .................................................................................. 5
Pin Configuration and Function Descriptions ............................. 6
Typical Performance Characteristics ............................................. 7
REVISION HISTORY
11/08—Revision 0: Initial Version
Theory of Operation ...................................................................... 12
Overview ..................................................................................... 12
Charge Pump Operation ........................................................... 12
Applications Information .............................................................. 13
Using the ADA4859-3 in Gains Equal to +1, −1 ........................ 13
Video Line Driver ....................................................................... 14
Power-Down ............................................................................... 14
Layout Considerations ............................................................... 14
Power Supply Bypassing ............................................................ 14
Outline Dimensions ....................................................................... 15
Ordering Guide .......................................................................... 15
Rev. 0 | Page 2 of 16
ADA4859-3
www.BDTIC.com/ADI
SPECIFICATIONS
TA = 25°C, VS = 5 V, G = 2, RF = 550 Ω, RL = 150 Ω, unless otherwise noted.
Table 1.
Parameter Conditions Min Typ Max Unit
DYNAMIC PERFORMANCE
−3 dB Bandwidth V
V
Bandwidth for 0.1 dB Flatness V
Slew Rate V
Settling Time to 0.1% V
NOISE/DISTORTION PERFORMANCE
Harmonic Distortion (HD2/HD3) fC = 1 MHz, VO = 2 V p-p −84/−93 dBc
f
Crosstalk f = 5 MHz −80 dBc
Total Output Noise f = 1 MHz 17 nV/√Hz
Input Current Noise f = 1 MHz 2 pA/√Hz
Differential Gain Error 0.01 %
Differential Phase Error 0.02 Degrees
DC PERFORMANCE
Output Offset Voltage −25 +9 +25 mV
+Input Bias Current −2 +0.7 +2 μA
Closed-Loop Gain 1.9 2 2.1 V/V
INPUT CHARACTERISTICS
Input Resistance +IN 15 MΩ
Input Capacitance +IN 1.5 pF
Input Common-Mode Voltage Range −1.8 +3.8 V
OUTPUT CHARACTERISTICS
Output Voltage Swing −1.4 to +3.6 −1.7 to +3.8 V
Output Overdrive Recovery Time Rise/fall, f = 5 MHz 15 ns
Maximum Linear Output Current @ VO = 1 V
POWER-DOWN
Input Voltage Enabled 1.9 V
Powered down 2 V
Bias Current −0.1 +0.1 μA
Turn-On Time 0.5 μs
Turn-Off Time 2 μs
POWER SUPPLY
Operating Range 3 5.5 V
Total Quiescent Current
Amplifier 15 17 21 mA
Charge Pump 21 mA
Total Quiescent Current When Powered Down
Amplifier 0.15 0.25 0.3 mA
Charge Pump 4 mA
Positive Power Supply Rejection Ratio Referred to output −55 −50 dB
Negative Power Supply Rejection Ratio Referred to output −51 −47 dB
Charge Pump Output Voltage −3.2 −3 −2.5 V
Charge Pump Sink Current 150 mA
f
PEAK
= 0.1 V p-p 265 MHz
OUT
= 2 V p-p 195 MHz
OUT
= 2 V p-p, CL = 6 pF 60 MHz
OUT
= 2 V step 740 V/μs
OUT
= 2 V step 20 ns
OUT
= 5 MHz, VO = 2 V p-p −70/−83 dBc
C
= 1 MHz, HD2 ≤ −50 dBc 19 mA
C
Rev. 0 | Page 3 of 16
ADA4859-3
www.BDTIC.com/ADI
TA = 25°C, VS = 3.3 V, G = 2, RF = 550 Ω, RL = 150 Ω, unless otherwise noted.
Table 2.
Parameter Conditions Min Typ Max Unit
DYNAMIC PERFORMANCE
−3 dB Bandwidth V
V
Bandwidth for 0.1 dB Flatness V
Slew Rate V
Settling Time to 0.1% V
NOISE/DISTORTION PERFORMANCE
Total Harmonic Distortion fC = 1 MHz, VO = 2 V p-p −84/−86 dBc
f
Crosstalk f = 5 MHz −80 dBc
Total Output Noise f = 1 MHz 17 nV/√Hz
Input Current Noise f = 1 MHz 2 pA/√Hz
Differential Gain Error 0.02 %
Differential Phase Error 0.03 Degrees
DC PERFORMANCE
Output Offset Voltage −25 +9 +25 mV
+Input Bias Current −2 +0.7 +2 μA
Closed-Loop Gain 1.9 2 2.1 V/V
INPUT CHARACTERISTICS
Input Resistance +IN 15 MΩ
Input Capacitance +IN 1.5 pF
Input Common-Mode Voltage Range −0.9 +2.2 V
OUTPUT CHARACTERISTICS
Output Voltage Swing −0.7 to +2.1 −1 to +2.3 V
Output Overdrive Recovery Time Rise/fall, f = 5 MHz 15 ns
Maximum Linear Output Current @ VO = 1 V
POWER-DOWN
Input Voltage Enabled 1.25 V
Powered down 1.35 V
Bias Current −0.1 +0.1 μA
Turn-On Time 0.5 μs
Turn-Off Time 2 μs
POWER SUPPLY
Operating Range 3 5.5 V
Total Quiescent Current
Amplifier 14 17 20 mA
Charge Pump 19 mA
Total Quiescent Current When Powered Down
Amplifier 0.15 0.25 0.3 mA
Charge Pump 2 mA
Positive Power Supply Rejection Ratio Referred to output −54 −50 dB
Negative Power Supply Rejection Ratio Referred to output −50 −47 dB
Charge Pump Output Voltage −2.1 −2 −1.8 V
Charge Pump Sink Current 45 mA
f
PEAK
= 0.1 V p-p 260 MHz
OUT
= 2 V p-p 165 MHz
OUT
= 2 V p-p, CL = 6 pF 65 MHz
OUT
= 2 V step, RL = 150 Ω 530 V/μs
OUT
= 2 V step 20 ns
OUT
= 5 MHz, VO = 2 V p-p −73/−77 dBc
C
= 1 MHz, HD2 ≤ −50 dBc 18 mA
C
Rev. 0 | Page 4 of 16
ADA4859-3
www.BDTIC.com/ADI
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter Rating
Supply Voltage 6 V
Internal Power Dissipation1
16-Lead LFCSP See Figure 2
Input Voltage (Common-Mode) (−VS − 0.2 V) to (+VS − 1.8 V)
Differential Input Voltage ±VS
Output Short-Circuit Duration Observe power derating curves
Storage Temperature Range −65°C to +125°C
Operating Temperature Range −40°C to +105°C
Lead Temperature
(Soldering, 10 sec)
1
Specification is for device in free air.
300°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.
MAXIMUM POWER DISSIPATION
The maximum power that can be safely dissipated by the
ADA4859-3 is limited by the associated rise in junction
temperature. The maximum safe junction temperature
for plastic encapsulated devices is determined by the glass
transition temperature of the plastic, approximately 150°C.
Temporarily exceeding this limit may cause a shift in parametric
performance due to a change in the stresses exerted on the die
by the package. Exceeding a junction temperature of 175°C for
an extended period can result in device failure.
To ensure proper operation, it is necessary to observe the
maximum power derating curves in Figure 2.
2.5
2.0
1.5
1.0
0.5
MAXIMUM POWER DISSIPATION (W)
0
–40 –20 0 20 40 60 80 100
Figure 2. Maximum Power Dissipation vs. Ambient Temperature
AMBIENT TEMP ERATURE (°C)
07715-002
ESD CAUTION
Rev. 0 | Page 5 of 16
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