ANALOG DEVICES ADA4855-3 Service Manual

Single Supply, High Speed,

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FEATURES

Voltage feedback architecture
Rail-to-rail output swing: 0.1 V to 4.9 V
High speed amplifiers

410 MHz, −3 dB bandwidth, G = 1
210 MHz, −3 dB bandwidth, G = 2
Slew rate: 870 V/μs
53 MHz, 0.1 dB large signal flatness

5.3 ns settling time to 0.1% with 2 V step

High input common-mode voltage range

−V

− 0.2 V to +VS − 1 V

S

Supply range: 3 V to 5.5 V
Differential gain error: 0.01%
Differential phase error: 0.01°
Low power

7.8 mA/amplifier typical supply current
Power-down feature

Available in 16-lead LFCSP

APPLICATIONS

Professional video
Consumer video
Imaging
Instrumentation
Base stations
Active filters

GENERAL DESCRIPTION

The ADA4855-3 (triple) is a single-supply, rail-to-rail output
operational amplifier. It provides excellent high speed performance
with 410 MHz, −3 dB bandwidth and a slew rate of 870 V/μs. It
has a wide input common-mode voltage range that extends from

0.2 V below ground to 1 V below the positive rail.In addition,
the output voltage swings within 100 mV of either supply rail,
making this rail-to-rail operational amplifier easy to use on single­supply voltages as low as 3.3 V.

The ADA4855-3 offers a typical low power of 7.8 mA per amplifier
and is capable of delivering up to 57 mA of load current. It also
features a power-down function for power sensitive applications
that reduces the supply current down to 1 mA.

The ADA4855-3 is available in a 16-lead LFCSP and is designed
to work over the extended industrial temperature range of

−40°C to +105°C.

Rail-to-Rail Output, Triple Op Amp

ADA4855-3

CONNECTION DIAGRAM

+IN1

16 15 14 13

1

NC

2+IN2

NC

PD

1

0

–1

–2

–3

–4

–5

NORMALIZED CLOSED-L OOP GAIN (dB)

–6

110

ADA4855-3

3

4

5678

+IN3

NOTES

1. NC = NO CONNECT .

2. EXPOSE D PAD CONNECTED TO –V

Figure 1.

G = 5

FREQUENCY (MHz)

Figure 2. Frequency Response

S

–IN1

OUT1

–V

12

+V

S

OUT2

11

–IN2

10

+V

9

S

S

–V

–IN3

OUT3

.

S

07685-001

G = 1

G = 2

100 1000

07685-004

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.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2008 Analog Devices, Inc. All rights reserved.

ADA4855-3

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TABLE OF CONTENTS

Features .............................................................................................. 1

Applications ....................................................................................... 1 

Connection Diagram ....................................................................... 1

General Description ......................................................................... 1

Revision History ............................................................................... 2

Specifications ..................................................................................... 3

5 V Operation ............................................................................... 3

3.3 V Operation ............................................................................ 4

Absolute Maximum Ratings ............................................................ 5

Thermal Resistance ...................................................................... 5

Maximum Power Dissipation ..................................................... 5

ESD Caution .................................................................................. 5

Pin Configuration and Function Descriptions ............................. 6

Typical Performance Characteristics ............................................. 7

Test Circuits ..................................................................................... 13

Theory of Operation ...................................................................... 14

Applications Information .............................................................. 15

Gain Configurations .................................................................. 15

20 MHz Active Low-Pass Filter ................................................ 15

RGB Video Driver ...................................................................... 16

Driving Multiple Video Loads .................................................. 16

(Power-Down) Pin .............................................................. 16

PD

Single-Supply Operation ........................................................... 17

Power Supply Bypassing ............................................................ 17

Layout .......................................................................................... 17

Outline Dimensions ....................................................................... 18

Ordering Guide .......................................................................... 18

REVISION HISTORY

11/08—Revision 0: Initial Version

Rev. 0 | Page 2 of 20

ADA4855-3

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SPECIFICATIONS

5 V OPERATION

TA = 25°C, VS = 5 V, G = 1, RL = 150 Ω, unless otherwise noted.

Table 1.

Parameter Test Conditions Min Typ Max Unit

DYNAMIC PERFORMANCE

−3 dB Bandwidth VO = 0.1 V p-p 410 MHz
V
V
V
Bandwidth for 0.1 dB Flatness VO = 2 V p-p 53 MHz
V
Slew Rate VO = 2 V step 870 V/μs
Settling Time to 0.1% VO = 2 V step (rise/fall) 5.3/9.5 ns
V

NOISE/DISTORTION PERFORMANCE

Harmonic Distortion (HD2/HD3) fC = 5 MHz, VO = 2 V p-p, RL = 1 kΩ −84/−105 dBc
f
Crosstalk, Output to Output f = 5 MHz, G = 2 −90 dBc
Input Voltage Noise f = 100 kHz 6.8 nV/√Hz
Input Current Noise f = 100 kHz 2 pA/√Hz
Differential Gain Error G = 2 0.01 %
Differential Phase Error G = 2 0.01 Degrees

DC PERFORMANCE

Input Offset Voltage 1.3 3 mV
Input Offset Voltage Drift 5.5 μV/°C
Input Bias Current −3.8 μA
Input Offset Current ±0.05 μA
Open-Loop Gain VO = 0.5 V to 4.5 V 92 dB

INPUT CHARACTERISTICS

Input Resistance 6.4 MΩ
Input Capacitance 0.5 pF
Input Common-Mode Voltage Range −VS − 0.2 +VS − 1 V
Common-Mode Rejection Ratio VCM = –0.2 V to +4 V 94 dB

OUTPUT CHARACTERISTICS

Output Voltage Swing 0.1 to 4.9 V
Linear Output Current per Amplifier HD2 ≤ −60 dBc, RL = 10 Ω 57 mA

POWER-DOWN

Turn-On Time 78 ns
Turn-Off Time 1.2 μs
Bias Current On 0.3 μA
Off −125 μA
Turn-On Voltage +VS − 1.25 V

POWER SUPPLY

Operating Range 3 5.5 V
Quiescent Current per Amplifier 7.8 mA
Supply Current When Powered Down 1.1 mA
Power Supply Rejection Ratio ∆VS = 4.5 V to 5.5 V 96 dB

= 2 V p-p 200 MHz

O

= 0.1 V p-p, G = 2 210 MHz

O

= 2 V p-p, G = 2 120 MHz

O

= 2 V p-p, G = 2 50 MHz

O

= 2 V step (rise/fall), G = 2 7.4/7 ns

O

= 20 MHz, VO = 2 V p-p, RL = 1 kΩ −60/−66 dBc

C

Rev. 0 | Page 3 of 20

ADA4855-3

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3.3 V OPERATION

TA = 25°C, VS = 3.3 V, G = 1, RL = 150 Ω, unless otherwise noted.

Table 2.

Parameter Test Conditions Min Typ Max Unit

DYNAMIC PERFORMANCE

−3 dB Bandwidth VO = 0.1 V p-p 430 MHz

V

V

V

Bandwidth for 0.1 dB Flatness VO = 1.4 V p-p, G = 2 55 MHz

Slew Rate VO = 2 V step, G = 2 870 V/μs

Settling Time to 0.1% VO = 2 V step (rise/fall), G = 2 7.4/7.1 ns
NOISE/DISTORTION PERFORMANCE

Harmonic Distortion (HD2/HD3) fC = 5 MHz, VO = 2 V p-p, RL = 1 kΩ −76/−76 dBc

f

Crosstalk, Output to Output f = 5 MHz, G = 2 −88 dBc

Input Voltage Noise f = 100 kHz 6.8 nV/√Hz

Input Current Noise f = 100 kHz 2 pA/√Hz

Differential Gain Error G = 2 0.01 %

Differential Phase Error G = 2 0.01 Degrees
DC PERFORMANCE

Input Offset Voltage 1.3 mV

Input Offset Voltage Drift 5.5 μV/°C

Input Bias Current −3.8 μA

Input Offset Current 0.05 μA

Open-Loop Gain VO = 0.5 V to 4.5 V 92 dB
INPUT CHARACTERISTICS

Input Resistance 6.4 MΩ

Input Capacitance 0.5 pF

Input Common-Mode Voltage Range −VS − 0.2 +VS − 1 V

Common-Mode Rejection Ratio VCM = –0.2 V to +3.2 V 94 dB
OUTPUT CHARACTERISTICS

Output Voltage Swing 0.1 to 3.22 V

Linear Output Current per Amplifier HD2 ≤ −60 dBc, RL = 10 Ω 40 mA
POWER-DOWN

Turn-On Time 78 ns

Turn-Off Time 1.2 μs

Turn-On Voltage +VS − 1.25 V
POWER SUPPLY

Operating Range 3 5.5 V

Quiescent Current per Amplifier 7.5 mA

Supply Current When Powered Down 0.95 mA

Power Supply Rejection Ratio ∆VS = 2.97 V to 3.63 V 94 dB

= 1.4 V p-p 210 MHz

O

= 0.1 V p-p, G = 2 210 MHz

O

= 2 V p-p, G = 2 125 MHz

O

= 20 MHz, VO = 2 V p-p, RL = 1 kΩ −68/−75 dBc

C

Rev. 0 | Page 4 of 20

ADA4855-3

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ABSOLUTE MAXIMUM RATINGS

Table 3.

Parameter Rating

Supply Voltage 6 V
Internal Power Dissipation1 See Figure 3
Common-Mode Input Voltage (−VS − 0.2 V) to (+VS − 1 V)
Differential Input Voltage ±VS
Output Short-Circuit Duration Observe power curves
Storage Temperature Range −65°C to +125°C
Operating Temperature Range −40°C to +105°C
Lead Temperature (Soldering, 10 sec) 300°C

1

Specification is for device in free air.

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 a device soldered in a circuit board for surface-mount packages.

Table 4.

Package Type θJA θ

16-Lead LFCSP 67 17.5 °C/W

Unit

JC

MAXIMUM POWER DISSIPATION

The maximum power that can be safely dissipated by the
ADA4855-3 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.

3.0

2.5

2.0

1.5

1.0

0.5

MAXIMUM POWER DISSIPATION (W)

0

–40

–30

Figure 3. Maximum Power Dissipation vs. Ambient Temperature

0

–20

102030405060708090

–10

AMBIENT TEMPERATURE (°C)

07685-103

100

ESD CAUTION

Rev. 0 | Page 5 of 20

ADA4855-3

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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

S

–IN1

+IN1

OUT1

–V

14

13

15

16

1NC

ADA4855-3

2+IN2

TOP VIEW

3NC

(Not to Scale)

4PD

5

6

–IN3

+IN3

NOTES

1. NC = NO CONNECT .

2. EXPOSE D PAD CONNECTED TO –V

12 +V

S

11 OU T2

10 –IN2

9+V

S

8

7

S

–V

OUT3

.

S

07685-003

Figure 4. Pin Configuration

Table 5. Pin Function Descriptions

Pin No. Mnemonic Description

1 NC No Connect.
2 +IN2 Noninverting Input 2.
3 NC No Connect.
4

PD

Power Down.

5 +IN3 Noninverting Input 3.
6 −IN3 Inverting Input 3.
7 OUT3 Output 3.
8 −VS Negative Supply.
9 +VS Positive Supply.
10 −IN2 Inverting Input 2.
11 OUT2 Output 2.
12 +VS Positive Supply.
13 −VS Negative Supply.
14 OUT1 Output 1.
15 −IN1 Inverting Input 1.
16 +IN1 Noninverting Input 1.
17 (EPAD) Exposed Pad (EPAD) The exposed pad must be connected to −VS.

Rev. 0 | Page 6 of 20