Datasheet ADA4850-1 Datasheet (ANALOG DEVICES)

High Speed, Rail-to-Rail Output

www.BDTIC.com/ADI

Op Amps with Ultralow Power-Down

FEATURES

Ultralow power-down current: 150 nA/amplifier maximum Low quiescent current: 2.4 mA/amplifier 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 Clock buffers

GENERAL DESCRIPTION

The ADA4850-1/ADA4850-21 are low price, high speed, voltage feedbacks rail-to-rail output op amps with ultralow powerdown. Despite their low price, the ADA4850-1/ADA4850-2 provide excellent overall performance and versatility. The 175 MHz, −3 dB bandwidth and 220 V/μs slew rate make these amplifiers well-suited for many general-purpose, high speed applications.

The ADA4850-1/ADA4850-2 are designed to operate at supply voltages as low as 2.7 V and up to 6 V at 2.4 mA of supply current per amplifier. In power-down mode, the supply current is less than 150 nA, ideal for 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. The output of the amplifier can swing within 80 mV of either supply rail.

With its combination of low price, excellent differential gain (0.12%), differential phase (0.09°), and 0.1 dB flatness out to 14 MHz, these amplifiers are ideal for video applications.

The ADA4850-1/ADA4850-2 are designed to work in the extended temperature range of −40°C to +125°C.

ADA4850-1/ADA4850-2

PIN CONFIGURATIONS

ADA4850-1

1POWER DOWN

NC

2

–IN

3 4+IN

NC = NO CONNECT

Figure 1. 8-Lead, 3 mm × 3 mm LFCSP

NC 16

ADA4850-2

1

1V

OUT

2–IN1 3+IN1 4–V

S

5 NC

NC = NO CONNECT

Figure 2. 16-Lead, 3 mm × 3 mm LFCSP

2

1

0

–1

–2

–3

CLOSED-LOOP GAIN (dB)

–4

G = +1

= 5V

V

S

–5

= 1kΩ

R

L

= 0.1V p-p

V

OUT

–6

1 10010 1000

FREQUENCY (MHz)

1

Patents pending.

Figure 3. Small Signal Frequency Response

PD2

NC

PD1

13

14

15

8

7

6

NC

+V

8

OUTPUT

7

NC

6

–V

5

12 +V 11 V

OUT

10 –IN2 9 +IN2

S

05320-106

S

2

05320-043

05320-054

Rev. B

Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her 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.

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

REVISION HISTORY

12/07—Rev. A to Rev. B

Changes to Applications .................................................................. 1

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

Changes to Ordering Guide.......................................................... 14

4/05—Rev. 0 to Rev. A

Added ADA4850-1.............................................................Universal

Added 8-Lead LFCSP.........................................................Universal

Changes to Features.......................................................................... 1

Changes to General Description .................................................... 1

Changes to Figure 3.......................................................................... 1

Changes to Table 1............................................................................ 3

Changes to Table 2............................................................................ 4

Changes to Power-Down Pins Section and Table 5 ................... 13

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

Changes to Ordering Guide.......................................................... 14

2/05—Revision 0: Initial Version

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

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

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

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

Operating the ADA4850-1/ADA4850-2 on Bipolar

Supplies........................................................................................ 13

Power-Down Pins....................................................................... 13

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

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

Rev. B | Page 2 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

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 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 Settling Time to 0.1% G = +2, VO = 1 V step, RL = 150 Ω 80 ns

NOISE/DISTORTION PERFORMANCE

Harmonic Distortion (dBc) HD2/HD3 fC = 1 MHz, VO = 2 V p-p, G = +3, RL = 150 Ω −72/−77 dBc Input Voltage Noise f = 100 kHz 10 nV/√Hz Input Current Noise f = 100 kHz 2.5 pA/√Hz 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 μV/°C Input Bias Current 2.4 4.4 μA Input Bias Current Drift 4 nA/°C Input Bias Offset Current 30 nA Open-Loop Gain VO = 0.25 V to 0.75 V 78 100 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 ADA4850-1/ADA4850-2 <0.7/<0.6 V Enabled ADA4850-1/ADA4850-2 >0.8/>1.7 V Turn-Off Time 0.7 μs Turn-On Time 60 ns Power-Down Bias Current/ Power Down Pin

Enabled Power-down = 3 V 37 55 μA Power-Down Power-down = 0 V 0.01 0.2 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 Quiescent Current/Amplifier 2.4 2.8 mA Quiescent Current (Power-Down)/Amplifier 15 150 nA 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 Operating the ADA4850-1/ADA4850-2 on Bipolar Supplies section.

1

2.7 6 V

Rev. B | Page 3 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

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

Harmonic Distortion (dBc) HD2/HD3 fC = 1 MHz, VO = 2 V p-p, G = +2, RL = 150 Ω −81/−86 dBc Input Voltage Noise f = 100 kHz 10 nV/√Hz Input Current Noise f = 100 kHz 2.5 pA/√Hz Differential Gain G = +3, NTSC, RL = 150 Ω 0.12 % Differential Phase G = +3, NTSC, RL = 150 Ω 0.09 Degrees Crosstalk (RTI)–ADA4850-2 f = 4.5 MHz, RL = 150 Ω, VO = 2 V p-p 60 dB

DC PERFORMANCE

Input Offset Voltage 0.6 4.2 mV Input Offset Voltage Drift 4 μV/°C Input Bias Current 2.3 4.2 μA Input Bias Current Drift 4 nA/°C Input Bias Offset Current 30 nA Open-Loop Gain VO = 2.25 V to 2.75 V 83 105 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 ADA4850-1/ADA4850-2 <0.7/<0.6 V Enabled ADA4850-1/ADA4850-2 >0.8/>1.7 V Turn-Off Time 0.7 μs Turn-On Time 50 ns Power-Down Bias Current/Power Down Pin

Enabled Power-down = 5 V 0.05 0.13 mA Power-Down Power-down = 0 V 0.02 0.2 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 Quiescent Current/Amplifier 2.5 2.9 mA Quiescent Current (Power-Down)/Amplifier 15 150 nA Positive Power Supply Rejection +VS = +5 V to +6 V, −VS = 0 V −84 −100 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 Operating the ADA4850-1/ADA4850-2 on Bipolar Supplies section.

1

2.7 6 V

Rev. B | Page 4 of 16

ADA4850-1/ADA4850-2

(

www.BDTIC.com/ADI

ABSOLUTE MAXIMUM RATINGS

Table 3.

Parameter Rating

Supply Voltage 12.6 V Power Dissipation See Figure 4 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.

THERMAL RESISTANCE

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

Table 4.

Package Type θ

JA

16-Lead LFCSP 91 °C/W 8-Lead LFCSP 80 °C/W

Maximum Power Dissipation

The maximum safe power dissipation for the ADA4850-1/ ADA4850-2 is limited by the associated rise in junction temperature (T

) on the die. At approximately 150°C, which

J

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 ADA4850-1/ADA4850-2. Exceeding a 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.

Unit

The power dissipated in the package (P cent power dissipation and the power dissipated in the die due to the ADA4850-1/ADA4850-2 drive at the output. The quiescent power is the voltage between the supply pins (V times the quiescent current (I

P

= Quiescent Power + (Tota l Dr i ve P o w er − Load Power)

D

⎛

()

D

⎜

IVP

SS

⎜ ⎝

).

S

V

OUTS

×+×=

R

2

RMS output voltages should be considered. If R to −V

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

S

V

× I

. If the rms signal levels are indeterminate, consider

S

OUT

the worst case, when V

()

D

IVP

SS

= VS/4 for RL to midsupply.

OUT

2

)

4V

/

S

+×=

R

L

In single-supply operation with R case is V

= VS/2.

OUT

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 4 shows the maximum safe power dissipation in the

ackage vs. the ambient temperature for the LFCSP (91°C/W)

p package on a JEDEC standard 4-layer board. θ approximations.

2.5

2.0 LFCSP-8

LFCSP-16

1.5

1.0

0.5

MAXIMUM POWER DISSIPATION (W)

0

–55 125–45–35–25–15–5 5 152535455565758595105115

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

AMBIENT TEMPERATURE (°C)

) is the sum of the quies-

D

⎞ ⎟ ⎟

L

⎠

referenced to −VS, the worst

L

2

V

OUT

−

R

L

is referenced

L

values are

JA

)

S

.

JA

05320-055

Rev. B | Page 5 of 16

ESD CAUTION

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

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

–1

–2

–3

–4

–5

NORMALIZED CLOSED-LOOP GAIN (dB)

–6

1 10 100

G = +10

FREQUENCY (MHz)

G = +2

VS = 5V

= 150Ω

R

L

V

OUT

= 0.1V p-p

Figure 5. Small Signal Frequency Response for Various Gains

2

1

0

–1

–2

–3

CLOSED-LOOP GAIN (dB)

–4

VS = 5V G = +1

–5

V

= 0.1V p-p

OUT

–6

1 10010 1000

RL = 1kΩ

FREQUENCY (MHz)

RL = 150Ω

Figure 6. Small Signal Frequency Response for Various Loads

3

2

1

0

–1

–2

–3

CLOSED-LOOP GAIN (dB)

–4

G = +1

= 150Ω

R

–5

L

V

= 0.1V p-p

OUT

–6

1 10010 1000

FREQUENCY (MHz)

VS = 5V

V

= 3V

S

Figure 7. Small Signal Frequency Response for Various Supplies

G = –1

05320-044

05320-045

05320-046

4

G = +1 V

= 5V

3

S

R

= 1kΩ

L

V

= 0.1V p-p

2

OUT

1

0

–1

–2

–3

CLOSED-LOOP GAIN (dB)

–4

–5

–6

1 10010 300

FREQUENCY (MHz)

1pF

0pF

6pF

Figure 8. Small Signal Frequency Response for Various Capacitor Loads

6.2

6.1

6.0

5.9

5.8

GAIN (dB)

5.7

5.6

5.5

5.4

VS = 5V, V

100k 100M

= 5V, V

V

S

OUT

VS = 3V, V

= 2V p-p

= 1.4V p-p

OUT

= 0.5V p-p

OUT

VS = 5V, V

1M 10M

= 0.1V p-p

OUT

FREQUENCY (Hz)

VS = 5V G = +2 R

= 150Ω

L

Figure 9. 0.1 dB Flatness Response

1

0

–1

–2

–3

–4

CLOSED-LOOP GAIN (dB)

–5

–6

–7

1 10010 1000

= 150Ω

R

L

= 1kΩ

R

L

FREQUENCY (MHz)

VS = 5V G = +1 V

OUT

= 0.5V p-p

Figure 10. Large Frequency Response for Various Loads

05320-007

05320-047

05320-048

Rev. B | Page 6 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

3

VS = 3V G = +1

2

R

= 1kΩ

L

V

= 0.1V p-p

OUT

1

0

–1

–2

CLOSED-LOOP GAIN (dB)

–3

–4

+25°C

–40°C

+125°C

+85°C

300

G = +2 V

= 5V

S

R

= 1kΩ

L

250

200

150

100

SLEW RATE (V/μs)

50

NEGATIVE SLEW RATE

POSITIVE SLEW RATE

–5

1 1000

10 100

FREQUENCY (MHz)

Figure 11. Small Signal Frequency Response for Various Temperatures

3

VS = 5V G = +1

2

R

= 1kΩ

L

V

= 0.1V p-p

OUT

1

0

–1

–2

CLOSED-LOOP GAIN (dB)

–3

–4

–5

1 1000

+25°C

–40°C

10 100

FREQUENCY (MHz)

+125°C

+85°C

Figure 12. Small Signal Frequency Response for Various Temperatures

140

120

100

80

60

PHASE

VS = 5V

0

–30

–60

–90

–120

05320-057

05320-098

0

0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

OUTPUT VOLTAGE STEP (V)

Figure 14. Slew Rate vs. Output Voltage

10k

1k

A)

μ

100

10

SUPPLY CURRENT (

1

0.1

0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

0

VS = 3V, 5V, ADA4850-2

VS = 3V, 5V, ADA4850-1 ENABLE

VS = 3V, 5V, ADA4850-1 POWER DOWN

POWER-DOWN VOLTAGE (V)

Figure 15. Supply Current vs. Power-Down Voltage

–40

G = +2 V

= 5V

S

R

= 150Ω

L

–50

V

= 2V p-p

OUT

–60

V

2 TO V

OUT

1

OUT

–70

5.0

05320-024

05320-036

40

OPEN-LOOP GAIN (dB)

20

0

–20

GAIN

100k10k100 1k10 1M 10M 100M 1G

FREQUENCY (Hz)

–150

–180

–210

–240

OPEN-LOOP PHASE (Degrees)

05320-012

Figure 13. Open-Loop Gain and Phase vs. Frequency

Rev. B | Page 7 of 16

–80

CROSSTALK (dB)

–90

–100

V

1 TO V

OUT

1M100k 10M 100M

FREQUENCY (Hz)

OUT

2

Figure 16. Crosstalk vs. Frequency

05320-037

ADA4850-1/ADA4850-2

–

www.BDTIC.com/ADI

–50

40

G = +1 V

= 5V

S

V

= 500mV p-p

OUT

2.575

2.550

G = +1 V

= 5V

S

R

= 150Ω

L

10pF

0pF

–60

R

= 1kΩ HD2

–70

–80

–90

HARMONIC DISTORTION (dBc)

–100

–110

0.1 100

L

RL = 150Ω HD2

= 1kΩ HD3

R

L

R

= 150Ω HD3

L

110

FREQUENCY (MHz)

Figure 17. Harmonic Distortion vs. Frequency for Various Loads

50

G = +2 V

= 5V

S

R

= 1kΩ

L

–60

–70

V

OUT

–80

–90

–100

HARMONIC DISTORTION (dBc)

–110

–120

0.1 100

V

= 200mV p-p

HD2

= 500mV p-p

OUT

HD2

V

= 200mV p-p

OUT

HD3

V

= 500mV p-p

OUT

HD3

110

FREQUENCY (MHz)

Figure 18. Harmonic Distortion vs. Frequency for Various V

0.65 G = +2 R

= 1kΩ

L

V

= 5V

S

0.60

OUT

05320-102

05320-103

2.525

2.500

2.475

OUTPUT VOLTAGE (V)

2.450

2.425 0 20 40 60 80 100 120 140 160 180 200

TIME (ns)

Figure 20. Small Signal Transient Response for Capacitive Load

3.25 G = +2 R

= 1kΩ

L

V

= 5V

S

3.00

2.75

2.50

2.25

2.00

OUTPUT VOLTAGE FOR 5V SUPPLY (V)

1.75

500 100 150 200

TIME (ns)

Figure 21. Large Signal Transient Response

2.875 G = +1

R

= 1kΩ

L

2.750

0.875

0.750

05320-020

05320-050

0.55

0.50

0.45

OUTPUT VOLTAGE (V)

0.40

0.35 500 100 150 200

TIME (ns)

05320-019

Figure 19. Small Signal Transient Response for Various Supplies

Rev. B | Page 8 of 16

2.625

2.500

OUTPUT VOLTAGE FOR 5V SUPPLY (V)

2.375

2.250

2.125

= 3V

V

S

500 100 150 200

TIME (ns)

VS = 5V

Figure 22. Large Signal Transient Response for Various Supplies

0.625

0.500

0.375

0.250

0.125

OUTPUT VOLTAGE FOR 3V SUPPLY (V)

05320-049

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

6

5

V

4

DISABLE

3

2

VOLTAGE (V)

1

0

–1

03015 45

V

OUT

TIME (μs)

Figure 23. Enable/Disable Time

G = +2 V

= 5V

S

f

= 400kHz

IN

05320-025

1000

100

10

VOLTAGE NOISE (nV/ Hz)

1

100k10k100 1k10 1M 10M 100M

FREQUENCY (Hz)

Figure 26. Voltage Noise vs. Frequency

05320-059

5.5

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

INPUT AND OUTPUT VOLTAGE (V)

0.5 0

–0.5

0 1000

OUTPUT

100 200 300 400 500 600 700 800 900

INPUT

TIME (ns)

Figure 24. Input Overdrive Recovery

3.5

3.0

2.5

2.0

1.5

1.0

0.5

INPUT AND OUTPUT VOLTAGE (V)

0

–0.5

0 1000

5 × INPUT

100 200 300 400 500 600 700 800 900

Figure 25. Output Ove

OUTPUT

TIME (ns)

rdrive Recovery

G = +1 V

= 5V

S

R

= 150Ω

L

f = 1MHz

G = +5 V

= 3V

S

R

= 150Ω

L

f = 1MHz

05320-058

05320-060

100

10

CURRENT NOISE (pA/ Hz)

1

100k10k100 1k10 1M 10M 100M 1G

FREQUENCY (Hz)

Figure 27. Current Noise vs. Frequency

350

VS = 5V N = 1720

300

x = 450μV σ = 750μV

250

200

COUNT

150

100

50

0

–4 4

–3 –2 –1 0 1 2 3

V

(mV)

OFFSET

Figure 28. Input Offset Voltage Distribution

05320-095

05320-065

Rev. B | Page 9 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

400

380

360

340

320

V)

μ

(

300

OS

V

280

260

240

220

200

–1.0 3.5

VS = 5V

–0.5 0 0.5 1.0 1.5 2.0 2.5 3.0

VCM (V)

Figure 29. Input Offset Voltage vs. Common-Mode Voltage

05320-063

–1.2

+I

B

–1.4

–1.6

VS = 5V

–1.8

–2.0

INPUT BIAS CURRENT (μA)

–2.2

–2.4

–40

–25–105203550658095110

TEMPERATURE (°C)

VS = 3V

–I

B

125

Figure 32. Input Bias Current vs. Temperature for Various Supplies

05320-092

0.6

0.5

0.4

0.3

0.2

0.1

OUTPUT SATURATION VOLTAGE (V)

0

05

5 1015202530354045

LOAD CURRENT (mA)

VS = 3V

+V

SAT

–V

SAT

VS = 5V

0

05320-064

Figure 30. Output Saturation Voltage vs. Load Current

(

Voltage Differential from Rails)

–30

–32

–34

–36

–38

–40

–42

–44

POWER-DOWN PIN BIAS CURRENT (μA)

–46

–25–105203550658095110

–40 125

VS = 3V

VS = 5V

TEMPERATURE (°C)

05320-091

Figure 31. Power-Down Bias Current vs. Temperature for Various Supplies

95

VS = 5V R

= 1k

L

90

85

80

75

70

OUTPUT SATURATION VOLTAGE (mV)

65

–40 125

–25–105203550658095110

Figure 33. Output Saturation Voltage vs. Temperature

4.9

4.8

4.7

4.6

4.5

4.4

SUPPLY CURRENT (mA)

4.3

4.2 –40

Figure 34. Current vs. Temperature for Various Supplies

Ω

+VS– V

OUT

–VS– V

OUT

TEMPERATURE (°C)

Voltage Differential from Rails)

(

VS = 5V

VS = 3V

–25–105203550658095110

TEMPERATURE (°C)

125

05320-062

05320-090

Rev. B | Page 10 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

COMMON-MODE REJECTION (dB)

–20

VS = 5V

–30

–40

–50

–60

–70

–80

–90

–100

–110

–120

1k

10k 100k 1M 10M 100M

CHANNEL 1

CHANNEL 2

FREQUENCY (Hz)

Figure 37. Common-Mode Rejection (CMR) vs. Frequency

0

VS = 5V

–10 –20 –30 –40 –50 –60 –70 –80 –90

POWER SUPPLY REJECTION (dB)

–100

–110

100

Figure 35. Power Supply Rejecti

0.7

0.6

+PSR

FREQUENCY (Hz)

on (PSR) vs. Frequency

–PSR

1M100k1k 10k 10M 100M

05320-094

05320-034

INPUT OFFSET VOLTAGE (mV)

0.5

0.4

0.3

0.2

0.1

0

–0.1

–25–105203550658095110

–40

VS = 5V

VS = 3V

TEMPERATURE (°C)

Figure 36. Input Offset Voltage vs. Temperature for Various Supplies

05320-093

125

Rev. B | Page 11 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

CIRCUIT DESCRIPTION

The ADA4850-1/ADA4850-2 feature a high slew rate input stage that is a true single-supply topology, capable of sensing signals at or below the negative supply rail. The rail-to-rail output stage can swing to within 80 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.

HEADROOM AND OVERDRIVE RECOVERY CONSIDERATIONS

Input

The ADA4850-1/ADA4850-2 are designed for use in low voltage systems. To obtain optimum performance, it is useful to understand the behavior of the amplifier as input and output signals approach the amplifier’s headroom limits. The input common-mode voltage range extends 200 mV below the negative supply voltage or ground for single-supply operation to within 2.2 V of the positive supply voltage. Therefore, in a gain of +3, the ADA4850-1/ADA4850-2 can provide full railto-rail output swing for supply voltage as low as 3.3 V, assuming the input signal swing is from −V

Exceeding the headroom limit is not a concern for any inverting ga

in on any supply voltage, as long as the reference voltage at the amplifier’s positive input lies within the amplifier’s input common-mode range.

The input stage sets the headroom limit for signals when the a

mplifier is used in a gain of +1 for signals approaching the positive rail. For high speed signals, however, there are other considerations. v

oltage for a unity-gain follower. As the common-mode voltage

Figure 38 shows −3 dB bandwidth vs. dc input

approaches the positive supply, the bandwidth begins to drop when within 2 V of +V

. This can manifest itself in increased

S

distortion or settling time.

2

1

0

–1

–2

GAIN (dB)

–3

–4

VS = 5V G = +1 R

= 1k

Ω

L

–5

V

= 0.1V p-p

OUT

–6

0.1 1000

1 10 100

FREQUENCY (MHz)

Figure 38. Unity-Gain Follow

Frequency for Various Input Common-Mode

(or ground) to 1.1 V.

S

VCM = 3V V

= 3.1V

CM

V

= 3.2V

CM

V

= 3.3V

CM

er Bandwidth vs.

05320-096

Higher frequency signals require more headroom than the lower frequencies to maintain distortion performance. Figure 39 i

llustrates how the rising edge settling time for the amplifier configured as a unity-gain follower stretches out as the top of a 1 V step input approaches and exceeds the specified input common-mode voltage limit.

3.6 VS = 5V

3.4

G = +1 R

= 1k

Ω

L

3.2

3.0

2.8

2.6

2.4

OUTPUT VOLTAGE (V)

2.2

2.0

1.8

0 100

10 20 30 40 50 60 70 80 90

V

STEP

V

= 2.1V TO 3.1V

STEP

V

STEP

V

STEP

TIME (ns)

= 2V TO 3V

= 2.2V TO 3.2V

= 2.3V TO 3.3V

= 2.4V TO 3.4V

V

STEP

Figure 39. Pulse Response, Input Headroom Limits

The recovery time from input voltages 2.2 V or closer to the positive supply is approximately 50 ns, which is limited by the settling artifacts caused by transistors in the input stage coming out of saturation.

The ADA4850-1/ADA4850-2 do not exhibit phase reversal, even f

or 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 increase the current draw of the devices.

Output

For signals approaching the negative supply and inverting gain, and high positive gain configurations, the headroom limit is the output stage. The ADA4850-1/ADA4850-2 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 drive current, due to the output transistor collector resistance.

As the saturation point of the output stage is approached, the

utput signal shows increasing amounts of compression and

o clipping. As in the input headroom case, higher frequency signals require a bit more headroom than the lower frequency signals.

Output overload recovery is typically within 40 ns after the a

mplifier’s input is brought to a nonoverloading value.

05320-061

Rev. B | Page 12 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

Figure 40 shows the output recovery transients for the amplifier recovering from a saturated output from the top and bottom supplies to a point at midsupply.

6.5

V

= +2.5V TO 0V

5.5

4.5

3.5 INPUT

2.5

VOLTAGE EDGES

1.5

0.5

INPUT AND OUTPUT VOLTAGE (V)

–0.5

–1.5

0 100

10 20 30 40 50 60 70 80 90

Figure 40. Overload Recovery

OUT

V

TIME (ns)

= –2.5V TO 0V

OUT

VS = 5V G = –1 R

= 1k

L

Ω

05320-042

OPERATING THE ADA4850-1/ADA4850-2 ON BIPOLAR SUPPLIES

The ADA4850-1/ADA4850-2 can operate on bipolar supplies

p to ±5 V. The only restriction is that the voltage between −V

u and the POWER DOWN pin must not exceed 6 V. Voltage differences greater than 6 V can cause permanent damage to the amplifier. For example, when operating on ±5 V supplies, the POWER DOWN pin must not exceed +1 V.

POWER-DOWN PINS

The ADA4850-1/ADA4850-2 feature an ultralow power-down mode that lowers the supply current to less than 150 nA. When a power-down pin is brought to within 0.6 V of the negative supply, the amplifier is powered down.

ower-down pins functionality. To ensure proper operation, the

p power-down pins (PD1, PD2) should not be left floating.

Table 5. Power-Down Pins Functionality

3 V and 5 V

Supply Voltage

ADA4850-1 ADA4850-2

Power Down 0 V to 0.7 V 0 V to 0.6 V Enabled 0.8 to +V

Table 5 outlines the

S

1.7 V to +V

S

Rev. B | Page 13 of 16

ADA4850-1/ADA4850-2

R

www.BDTIC.com/ADI

OUTLINE DIMENSIONS

INDICATOR

0.90 MAX

0.85 NOM

SEATING

PLANE

INDICATO

0.90

0.85

0.80

SEATING

PLANE

3.25

3.00 SQ

PIN 1

12° MAX

2.75

TOP

VIEW

0.70 MAX

0.65TYP

0.30

0.23

0.18

2.95

2.75 SQ

2.55

0.05 MAX

0.01 NOM

0.20 REF

0.60 MAX

Figure 41. 8-Lead Lead Frame Chip Scale Package [LFCSP_VD]

3

mm × 3 mm Body, Very Thin, Dual Lead

Dimensions shown in millimeters

3.00

BSC SQ

PIN 1

12° MAX

TOP

VIEW

0.30

0.23

0.18 *

COMPLIANT EXCEPT FOR EXPOSED PAD DIMENSION.

2.75

BSC SQ

0.80 MAX

0.65 TYP

0.05 MAX

0.02 NOM

0.20 REF

TO

JEDEC STANDARDS MO-220-VEED-2

Figure 42. 16-Lead Lead Frame Chip Scale Package [LFCSP_VQ]

3

mm × 3 mm Body, Very Thin Quad

(CP-16-3)

Dimensions shown in millimeters

0.50

0.40

0.30

(CP-8-2)

0.45

0.60 MAX

0.50 BSC

1.50 REF

0.60 MAX

5

EXPOSED

PAD

(BOTT OM VIEW)

4

13

12

EXPOSED

PAD

(BOTTOM VIEW)

9

8

0.50 BSC

8

1.60

1.45

1.30

1

16

PIN 1 INDICATOR

1.89

1.74

1.59

61507-B

0.50

0.40

0.30

1

4

5

N

I

P

D

N

I

*

1.65

1.50 SQ

1.35

0.25 MIN

1

O

T

C

I

A

ORDERING GUIDE

Model Temperature Range Package Description Package Option Branding

ADA4850-1YCPZ-R2 ADA4850-1YCPZ-RL ADA4850-1YCPZ-RL7 ADA4850-2YCPZ-R2 ADA4850-2YCPZ-RL ADA4850-2YCPZ-RL7

1

Z = RoHS Compliant Part.

1

−40°C to +125°C 8-Lead Lead Frame Chip Scale Package (LFCSP_VD) CP-8-2 HWB

1

−40°C to +125°C 8-Lead Lead Frame Chip Scale Package (LFCSP_VD) CP-8-2 HWB

1

−40°C to +125°C 8-Lead Lead Frame Chip Scale Package (LFCSP_VD) CP-8-2 HWB

1

−40°C to +125°C 16-Lead Lead Frame Chip Scale Package (LFCSP_VQ) CP-16-3 HTB

1

−40°C to +125°C 16-Lead Lead Frame Chip Scale Package (LFCSP_VQ) CP-16-3 HTB

1

−40°C to +125°C 16-Lead Lead Frame Chip Scale Package (LFCSP_VQ) CP-16-3 HTB

Rev. B | Page 14 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

NOTES

Rev. B | Page 15 of 16

ADA4850-1/ADA4850-2

www.BDTIC.com/ADI

NOTES

Rev. B | Page 16 of 16

Datasheet ADA4850-1 Datasheet (ANALOG DEVICES)

Specifications and Main Features

Frequently Asked Questions

User Manual

FEATURES

APPLICATIONS

GENERAL DESCRIPTION

PIN CONFIGURATIONS

TABLE OF CONTENTS

REVISION HISTORY

SPECIFICATIONS

SPECIFICATIONS WITH +3 V SUPPLY

SPECIFICATIONS WITH +5 V SUPPLY

ABSOLUTE MAXIMUM RATINGS

THERMAL RESISTANCE

Maximum Power Dissipation

ESD CAUTION

TYPICAL PERFORMANCE CHARACTERISTICS

CIRCUIT DESCRIPTION

HEADROOM AND OVERDRIVE RECOVERY CONSIDERATIONS

Input

Output

OPERATING THE ADA4850-1/ADA4850-2 ON BIPOLAR SUPPLIES

POWER-DOWN PINS

OUTLINE DIMENSIONS

ORDERING GUIDE