Analog Devices ADA4850 2 Datasheet

V

High Speed, Rail-to-Rail Output,

FEATURES

Ultralow power-down current: 0.3 µA/amp max
Low quiescent current: 2.4 mA/amp
High speed

175 MHz −3 dB bandwidth
220 V/µs slew rate
85 ns settling time to 0.1%

Excellent video specifications

0.1 dB flatness: 14 MHz
Differential gain: 0.12%

Differential phase: 0.09°
Single-supply operation: 2.7 V to 6 V
Rail-to-rail output

Output swings to within 80 mV of either rail
Low voltage offset: 0.6 mV

APPLICATIONS

Portable multimedia players
Video cameras
Digital still cameras
Consumer video

Op Amp with Ultralow Power Down

ADA4850-2

PIN CONFIGURATION

2
C
N

6

1

ADA4850-2

1

1

OUT

2–IN1

3+IN1

4–V

S

5
C

N

NC = NO CONNECT

Figure 1. 16-Lead, 3 mm × 3 mm LFCSP

1
C
N

5

1

6
C

N

D

D

P

P

4

3

1

1

12 +V

S

11 V

2

OUT

10 –IN2

9 +IN2

8

7

C

C

N

N

05320-043

GENERAL DESCRIPTION

The ADA4850-21 (dual) is a low price, high speed, voltage
feedback rail-to-rail output op amp with ultralow power-down.
Despite its low price, the ADA4850-2 provides excellent overall
performance and versatility. The 175 MHz −3 dB bandwidth
and 220 V/µs slew rate make this amplifier well-suited for many
general-purpose, high speed applications.

The ADA4850-2 is designed to operate at supply voltages as low
as 2.7 V and up to 6 V using only 2.4 mA of supply current per
amplifier. To further reduce power consumption, the amplifier
is equipped with a power-down mode, which lowers the supply
current to less than 0.1 µA, making it ideal in battery-powered
applications.

The ADA4850 family provides users with a true single-supply
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 amplifier can swing within 80 mV of either supply rail.

With its combination of low price, excellent differential gain
(0.12%), differential phase (0.09º), and 0.1 dB flatness out to
14 MHz, this amplifier is ideal for video applications.

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 Anal og Devices. Trademarks and
registered trademarks are the property of their respective owners.

The ADA4850-2 is available in a 16-lead, 3 mm × 3 mm LFCSP
and is designed to work in the extended temperature range
(−40°C to +125°C).

4

G = +1
V

= 5V

3

S

= 1kΩ

R

L

= 5pF

C

2

L

1

0

–1

–2

–3

CLOSED-LOOP GAIN (dB)

–4

–5

–6

1 10010 1k

FREQUENCY (MHz)

1

Patent pending.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone]
Fax: [phone] © 2005 Analog Devices, Inc. All rights reserved.

Figure 2. Small Signal Frequency Respon se

www.analog.com

05320-054

ADA4850-2

TABLE OF CONTENTS

Specifications with +3 V Supply..................................................... 3

Circuit Description......................................................................... 12

Specifications with +5 V Supply..................................................... 4

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

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

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

Typical Performance Characteristics............................................. 6

REVISION HISTORY

2/05—Revision 0: Initial Version

Headroom and Overdrive Recovery Considerations ............ 12

Operating the ADA4850-2 on Bipolar Supplies..................... 13

Power-Down Pin ........................................................................ 13

Outline Dimensions....................................................................... 14

Ordering Guide .......................................................................... 14

Rev. 0 | Page 2 of 16

ADA4850-2

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 Conditions Min Typ Max Unit

DYNAMIC PERFORMANCE

−3 dB Bandwidth G = +1, VO = 0.1 V p-p 160 MHz
G = +2, VO = 0.5 V p-p, RL = 150 Ω 45 MHz
Bandwidth for 0.1 dB Flatness G = +2, VO = 0.5 V p-p, RL = 150 Ω 14 MHz
Slew Rate G = +2, VO = 1 V Step 110 V/µs

NOISE/DISTORTION PERFORMANCE

Input Voltage Noise f = 100 kHz 10
Input Current Noise f = 100 kHz 2.5
Differential Gain G = +3, NTSC, RL = 150 Ω, VO = 2 V p-p 0.2 %
Differential Phase G = +3, NTSC, RL = 150 Ω, VO = 2 V p-p 0.2 Degrees

DC PERFORMANCE

Input Offset Voltage 0.6 4.1 mV
Input Offset Voltage Drift 4

Input Bias Current 2.4 4.4 µA
Input Bias Current Drift 4

Input Bias Offset Current 30 nA
Open-Loop Gain VO = 0.25 V to 0.75 V 78 102 dB

INPUT CHARACTERISTICS

Input Resistance Differential/common-mode 0.5/5.0 MΩ
Input Capacitance 1.2 pF
Input Common-Mode Voltage Range −0.2 to +0.8 V
Input Overdrive Recovery Time (Rise/Fall) VIN = +3.5 V to −0.5 V, G = +1 60/50 ns
Common-Mode Rejection Ratio VCM = 0.5 V −76 −108 dB

POWER-DOWN

Power-Down Input Voltage Power-down <0.6 V
Enabled >1.7 V
Turn-Off Time 0.7 µs
Turn-On Time 60 ns
Power-Down Bias Current

Enabled Power-down = 3 V 37 47 µA
Power-Down Power-down = 0 V 0.01 0.16 µA

OUTPUT CHARACTERISTICS

Output Overdrive Recovery Time (Rise/Fall) VIN = +0.7 V to −0.1 V, G = +5 70/100 ns
Output Voltage Swing 0.06 to 2.83 0.03 to 2.92 V
Short-Circuit Current Sinking/sourcing 105/74 mA

POWER SUPPLY

Operating Range

1

2.7 6 V
Quiescent Current Both amplifiers enabled 4.7 5.4 mA
Quiescent Current (Power-Down) Power-down = low <0.1 0.3 µA
Positive Power Supply Rejection +VS = +3 V to +4 V, −VS = 0 V −83 −100 dB
Negative Power Supply Rejection +VS = +3 V, −VS = 0 V to –1 V −83 −102 dB

1

For operation on bipolar supplies, see the section. Operating the ADA4850-2 on Bipolar Supplies

nV/√Hz
pA/√Hz

µV/°C

nA/°C

Rev. 0 | Page 3 of 16

ADA4850-2

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 Conditions Min Typ Max Unit

DYNAMIC PERFORMANCE

−3 dB Bandwidth G = +1, VO = 0.1 V p-p 175 MHz
G = +1, VO = 0.5 V p-p 110 MHz
Bandwidth for 0.1 dB Flatness G = +2, VO = 1.4 V p-p, RL = 150 Ω 9 MHz
Slew Rate G = +2, VO = 4 V Step 220 V/µs
G = +2, VO = 2 V Step 160 V/µs
Settling Time to 0.1% G = +2, VO = 1 V Step, RL = 150 Ω 85 ns

NOISE/DISTORTION PERFORMANCE

Input Voltage Noise f = 100 kHz 10
Input Current Noise f = 100 kHz 2.5
Differential Gain G = +3, NTSC, RL = 150 Ω 0.12 %
Differential Phase G = +3, NTSC, RL = 150 Ω 0.09 Degrees

DC PERFORMANCE

Input Offset Voltage 0.6 4.2 mV
Input Offset Voltage Drift 4

Input Bias Current 2.3 4.2 µA
Input Bias Current Drift 4

Input Bias Offset Current 30 nA
Open-Loop Gain VO = 2.25 V to 2.75 V 83 108 dB

INPUT CHARACTERISTICS

Input Resistance Differential/common-mode 0.5/5.0 MΩ
Input Capacitance 1.2 pF
Input Common-Mode Voltage Range −0.2 to +2.8 V
Input Overdrive Recovery Time (Rise/Fall) VIN = +5.5 V to −0.5 V, G = +1 50/40 ns
Common-Mode Rejection Ratio VCM = 2.0 V −85 −110 dB

POWER-DOWN

Power-Down Input Voltage Power-down <0.6 V
Enabled >1.7 V
Turn-Off Time 0.7 µs
Turn-On Time 50 ns
Power-Down Bias Current

Enabled Power-down = 5 V 52 71 µA
Power-Down Power-down = 0 V 0.02 0.17 µA

OUTPUT CHARACTERISTICS

Output Overdrive Recovery Time (Rise/Fall) VIN = +1.1 V to −0.1 V, G = +5 60/70 ns
Output Voltage Swing 0.14 to 4.83 0.07 to 4.92 V
Short-Circuit Current Sinking/sourcing 118/94 mA

POWER SUPPLY

Operating Range

1

2.7 6 V
Quiescent Current Both amplifiers enabled 4.9 5.6 mA
Quiescent Current (Power-Down) Power-down = low <0.1 0.3 µA
Positive Power Supply Rejection +VS = +5 V to +6 V, −VS = 0 V −84 −98 dB
Negative Power Supply Rejection +VS = +5 V, −VS = −0 V to −1 V −84 −102 dB

1

For operation on bipolar supplies, see the section. Operating the ADA4850-2 on Bipolar Supplies

nV/√Hz
pA/√Hz

µV/°C

nA/°C

Rev. 0 | Page 4 of 16

ADA4850-2

(

)

ABSOLUTE MAXIMUM RATINGS

Table 3.

Parameter Rating

Supply Voltage 12.6 V
Power Dissipation See Figure 3
Power Down Pin Voltage (−VS + 6) V
Common-Mode Input Voltage (−VS − 0.5 ) V to (+VS + 0.5) V
Differential Input Voltage +VS to −V

S

Storage Temperature −65°C to +125°C
Operating Temperature Range −40°C to +125°C
Lead Temperature Range

300°C

(Soldering 10 sec)

Junction Temperature 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.

The power dissipated in the package (P
quiescent power dissipation and the power dissipated in the die
due to the ADA4850-2 drive at the output. The quiescent power
is the voltage between the supply pins (V
current (I

).

S

= Quiescent Power + (Tot a l Dr i ve Po w e r − Load Power)

P

D

VV

⎛

S

()

D

IVP

SS

⎜
⎝

OUT

×+×=

R

2

L

RMS output voltages should be considered. If RL is referenced

, as in single-supply operation, the total drive power is

to −V

S

× I

V

the worst case, when V

. If the rms signal levels are indeterminate, consider

S

OUT

= VS/4 for RL to midsupply.

OUT

2

4/

V

()

D

S

+×=

IVP

SS

R

L

In single-supply operation with R
case is V

= VS/2.

OUT

) is the sum of the

D

) times the quiescent

S

2

V

⎞

OUT

–

⎟
⎠

referenced to −VS, the worst

L

R

L

THERMAL RESISTANCE

θJA is specified for the worst-case conditions, that is, θJA is
specified for the device soldered in the circuit board for surface­mount packages.

Table 4. Thermal Resistance

Package Type θ

JA

LFCSP 91 °C/W

Maximum Power Dissipation

Unit

Airflow increases heat dissipation, effectively reducing θ
Also, more metal directly in contact with the package leads and
exposed paddle from metal traces, through holes, ground, and
power planes reduce θ

.

JA

Figure 3 shows the maximum safe power dissipation in the
package vs. the ambient temperature for the LFCSP (91°C/W)
package on a JEDEC standard 4-layer board. θ
approximations.

2.5

The maximum safe power dissipation for the ADA4850-2 is
limited by the associated rise in junction temperature (T

) on

J

2.0

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 ADA4850-2. Exceeding a

1.5
LFCSP

1.0

junction temperature of 150°C for an extended period of time
can result in changes in silicon devices, potentially causing
degradation or loss of functionality.

0.5

MAXIMUM POWER DISSIPATION (W)

0

–40

–30 –20 –10 0 10 20 40 8030 50 60 70 10090 120110

AMBIENT TEMPERATURE (°C)

Figure 3. Maximum Power Dissipation vs. Temperature for a 4-Layer Board

ESD CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate
on the human body and test equipment and can discharge without detection. Although this product features
proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy
electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance
degradation or loss of functionality.

values are

JA

.

JA

05320-055

Rev. 0 | Page 5 of 16