ANALOG DEVICES ADA4930-1, ADA4930-2 Service Manual

Ultralow Noise



Drivers for Low Voltage ADCs

ADA4930-1/ADA4930-2

FEATURES

Low input voltage noise: 1.2 nV/√Hz Low common-mode output: 0.9 V on single supply Extremely low harmonic distortion

−104 dBc HD2 at 10 MHz

−79 dBc HD2 at 70 MHz

−73 dBc HD2 at 100 MHz

−101 dBc HD3 at 10 MHz

−82 dBc HD3 at 70 MHz

−75 dBc HD3 at 100 MHz

High speed

−3 dB bandwidth of 1.35 GHz, G = 1 Slew rate: 3400 V/μs, 25% to 75%

0.1 dB gain flatness to 380 MHz Fast overdrive recovery of 1.5 ns

0.5 mV typical offset voltage Externally adjustable gain Differential-to-differential or single-ended-to-differential

operation Adjustable output common-mode voltage Single-supply operation: 3.3 V or 5 V

APPLICATIONS

ADC drivers Single-ended-to-differential converters IF and baseband gain blocks Differential buffers Line drivers

GENERAL DESCRIPTION

The ADA4930-1/ADA4930-2 are very low noise, low distortion, high speed differential amplifiers. They are an ideal choice for driving 1.8 V high performance ADCs with resolutions up to 14 bits from dc to 70 MHz. The adjustable output common mode allows the ADA4930-1/ADA4930-2 to match the input of the ADC. The internal common-mode feedback loop provides exceptional output balance, suppression of even-order harmonic distortion products, and dc level translation.

With the ADA4930-1/ADA4930-2, differential gain configurations are easily realized with a simple external feedback network of four resistors determining the closed-loop gain of the amplifier.

The ADA4930-1/ADA4930-2 are fabricated using Analog Devices, Inc., proprietary silicon-germanium (SiGe), complementary bipolar process, enabling them to achieve very low levels of distortion with an input voltage noise of only 1.2 nV/√Hz.

Rev. A

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.

The low dc offset and excellent dynamic performance of the ADA4930-1/ADA4930-2 make them well suited for a wide variety of data acquisition and signal processing applications.

The ADA4930-1 is available in a Pb-free, 3 mm × 3 mm 16-lead LFCSP, and the ADA4930-2 is available in a Pb-free, 4 mm × 4 mm 24-lead LFCSP. The pinout has been optimized to facilitate printed circuit board (PCB) layout and minimize distortion. The ADA4930-1 is specified to operate over the −40°C to +105°C temperature range, and the ADA4930-2 is specified to operate over the −40°C to +105°C temperature range for 3.3 V or 5 V supply voltages.

FUNCTIONAL BLOCK DIAGRAMS

1–FB

2+IN

3–IN

4+FB

S

–V

14

15

16

ADA4930-1

7

5

6

S

+V

–V

13

8

+V

S

12 PD

11 –OUT

10 +OUT

9V

OCM

09209-001

Figure 1.

S1

–OUT1

–V

–FB1

PD1

+IN1

19

20

21

22

23

24

S1 S1

1–IN1 2+FB1 3+V

ADA4930-2

4+V 5–FB2 6+IN2

9

7

8

S2

–IN2

+V

+FB2

18 +O UT1 17 V

OCM1

16 –V

S2

–V

15

S2

14

PD2

13 –OUT2

11

12

10

2

S2

+V

OCM

V

+OUT2

09209-002

Figure 2.

100

10

hz)

(nV/

N

V

1

0

10 100 1k 10k 100k 1M 10M 100M

FREQUENCY (Hz)

Figure 3. Voltage Noise Spectral Density

09209-003

ADA4930-1/ADA4930-2

REVISION HISTORY

10/10—Rev. 0 to Rev. A

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

10/10—Revision 0: Initial Version

Rev. A | Page 2 of 28

ADA4930-1/ADA4930-2

SPECIFICATIONS

3.3 V OPERATION

VS = 3.3 V, V T

= −40°C to +105°C, unless otherwise noted.

MAX

Table 1.

Parameter Test Conditions/Comments Min Typ Max Unit

DYNAMIC PERFORMANCE

−3 dB Small Signal Bandwidth V

−3 dB Large Signal Bandwidth V Bandwidth for 0.1 dB Flatness V

ADA4930-1 380 MHz

ADA4930-2 89 MHz Slew Rate V Settling Time to 0.1% V Overdrive Recovery Time G = 3, V

NOISE/HARMONIC PERFORMANCE

HD2/HD3 V V V V Third-Order IMD V V Input Voltage Noise f = 100 kHz 1.15 nV/√Hz Input Current Noise f = 100 kHz 3 pA/√Hz Crosstalk f = 100 MHz, ADA4930-2, RL = 200 Ω −90 dB

DC PERFORMANCE

Input Offset Voltage VIP = VIN = V Input Offset Voltage Drift T Input Bias Current −36 −24 −16 μA Input Bias Current Drift T

Input Offset Current −1.8 +0.1 +1.8 μA Open-Loop Gain RF = RG = 10 kΩ, ΔVO = 0.5 V, RL = open circuit 64 dB

INPUT CHARACTERISTICS

Input Common-Mode Voltage Range 0.3 1.2 V Input Resistance Differential 150 kΩ Common mode 3 MΩ Input Capacitance Common mode 1 pF CMRR ΔV

OUTPUT CHARACTERISTICS

Output Voltage Each single-ended output; RF = RG = 10 kΩ 0.11 1.74 V Linear Output Current Each single-ended output; f = 1 MHz, TDH ≤ 60 dBc 30 mA Output Balance Error f = 1 MHz 55 dB

= 0.9 V, V

ICM

= 0.9 V, RF = 301 Ω, RG = 301 Ω, R

OCM

= 0.1 V p-p 1430 MHz

O, dm

= 2 V p-p 887 MHz

O, dm

= 0.1 V p-p

O, dm

= 2 V step, 25% to 75% 2877 V/μs

O, dm

= 2 V step, RL = 200 Ω 6.3 ns

O, dm

= 0.7 V p-p pulse 1.5 ns

IN, dm

= 2 V p-p, fC = 10 MHz −98/−97 dB

O, dm

= 2 V p-p, fC = 30 MHz −91/−88 dB

O, dm

= 2 V p-p, fC = 70 MHz −79/−79 dB

O, dm

= 2 V p-p, fC = 100 MHz −73/−73 dB

O, dm

= 1 V p-p/tone, fC = 70.05 MHz ± 0.05 MHz 91 dBc

O, dm

= 1 V p-p/tone, fC = 140.05 MHz ± 0.05 MHz 86 dBc

O, dm

OCM

to T

MIN

2.75 μV/°C

MAX

to T

−0.05

MAX

= 0.5 V dc; RF = RG = 10 kΩ, RL = open circuit −82 −77 dB

ICM

= 1 kΩ, single-ended input, differential output, TA = 25°C, T

L, dm

= 0 V, RL = open circuit

to

MIN

−3.1 −0.5 +3.1 mV

μA/°C

Rev. A | Page 3 of 28

ADA4930-1/ADA4930-2

3.3 V V

Table 2.

Parameter Test Conditions/Comments Min Typ Max Unit

V

DYNAMIC PERFORMANCE

OCM

−3 dB Bandwidth V Slew Rate V

V

INPUT CHARACTERISTICS

OCM

Input Voltage Range 0.8 1.1 V Input Resistance 7.0 8.3 10.3 kΩ Input Offset Voltage V Input Voltage Noise f = 100 kHz 23.5 nV/√Hz Gain 0.99 1 1.02 V/V CMRR ΔV

3.3 V GENERAL PERFORMANCE

Table 3.

Parameter Test Conditions/Comments Min Typ Max Unit

POWER SUPPLY

Operating Range 3.3 V Quiescent Current per Amplifier Enabled 32 35 40 mA Enabled, T

Disabled 0.44 1.8 2.35 mA +PSRR ΔV

−PSRR ΔV POWER-DOWN (PD) PD Input Voltage

Enabled >1.3 V Turn-Off Time 1 μs Turn-On Time 12 ns PD Pin Bias Current

Enabled

Disabled OPERATING TEMPERATURE RANGE −40 +105 °C

OCM

TO V

PERFORMANCE

O, CM

= 0.1 V p-p 745 MHz

O, cm

= 2 V p-p, 25% to 75% 828 V/μs

O, cm

= V

− V

OS, cm

O, cm

= 0.5 V dc; RF = RG = 10 kΩ, RL = open circuit −83 −77 dB

OCM

MIN

= 0.5 V; RF = RG = 10 kΩ, RL = open circuit −74 −70 dB

ICM

= 0.5 V; RF = RG = 10 kΩ, RL = open circuit −87 −76 dB

ICM

; VIP = VIN = V

OCM

to T

variation 81

MAX

= 0 V −25 +15.4 +31 mV

OCM

μA/°C

Disabled <0.8 V

PD PD

= 3.3 V = 0 V

0.09 μA 97 μA

Rev. A | Page 4 of 28

ADA4930-1/ADA4930-2

5 V OPERATION

VS = 5 V, V T

to T

MIN

Table 4.

Parameter Test Conditions/Comments Min Typ Max Unit

DYNAMIC PERFORMANCE

−3 dB Small Signal Bandwidth V

−3 dB Large Signal Bandwidth V Bandwidth for 0.1 dB Flatness V

ADA4930-1 369 MHz

ADA4930-2 90 MHz Slew Rate V Settling Time to 0.1% V Overdrive Recovery Time G = 3, V

NOISE/HARMONIC PERFORMANCE

HD2/HD3 V V V V Third-Order IMD V V Input Voltage Noise f = 100 kHz 1.2 nV/√Hz Input Current Noise f = 100 kHz 2.8 pA/√Hz Crosstalk f = 100 MHz, ADA4930-2, RL = 200 Ω −90 dB

DC PERFORMANCE

Input Offset Voltage VIP = VIN = V Input Offset Voltage Drift T Input Bias Current −34 −23 −15 μA Input Bias Current Drift T

Input Offset Current −0.82 +0.1 +0.82 μA Open-Loop Gain RF = RG = 10 kΩ, ΔVO = 1 V, RL = open circuit 64 dB

INPUT CHARACTERISTICS

Input Common-Mode Voltage Range 0.3 2.8 V Input Resistance Differential 150 kΩ Common mode 3 MΩ Input Capacitance Common mode 1 pF CMRR ΔV

OUTPUT CHARACTERISTICS

Output Voltage Each single-ended output; RF = RG = 10 kΩ 0.18 3.38 V Linear Output Current Each single-ended output; f = 1 MHz, TDH ≤ 60 dBc 30 mA Output Balance Error f = 1 MHz 55 dB

= 0.9 V, V

ICM

= −40°C to +105°C, unless otherwise noted.

MAX

= 0.9 V, RF = 301 Ω, RG = 301 Ω, R

OCM

= 0.1 V p-p 1350 MHz

O, dm

= 2 V p-p 937 MHz

O, dm

= 0.1 V p-p

O, dm

= 2 V step, 25% to 75% 3400 V/μs

O, dm

= 2 V step, RL = 200 Ω 6 ns

O, dm

IN, dm

= 2 V p-p, fC = 10 MHz −104/−101 dB

O, dm

= 2 V p-p, fC = 30 MHz −91/−93 dB

O, dm

= 2 V p-p, fC = 70 MHz −79/−82 dB

O, dm

= 2 V p-p, fC = 100 MHz −73/−75 dB

O, dm

= 1 V p-p/tone, fC = 70.05 MHz ± 0.05 MHz 94 dBc

O, dm

= 1 V p-p/tone, fC = 140.05 MHz ± 0.05 MHz 90 dBc

O, dm

to T

MIN

MAX

to T

MIN

MAX

= 1 V dc; RF = RG = 10 kΩ, RL = open circuit −82 −77 dB

ICM

= 1 kΩ, single-ended input, differential output, TA= 25°C,

L, dm

= 0.7 V p-p pulse 1.5 ns

= 0 V, RL = open circuit

OCM

−3.1 −0.15 +3.1 mV

1.8 μV/°C

−0.05

μA/°C

Rev. A | Page 5 of 28

ADA4930-1/ADA4930-2

5 V V

Table 5.

Parameter Test Conditions/Comments Min Typ Max Unit

V

OCM

V

OCM

5 V GENERAL PERFORMANCE

Table 6.

Parameter Test Conditions/Comments Min Typ Max Unit

POWER SUPPLY

POWER-DOWN (PD) PD Input Voltage

Turn-Off Time 1 μs Turn-On Time 12 ns PD Pin Bias Current

OPERATING TEMPERATURE RANGE −40 +105 °C

OCM

TO V

PERFORMANCE

O, CM

DYNAMIC PERFORMANCE

−3 dB Bandwidth V Slew Rate V

= 0.1 V p-p 740 MHz

O, cm

= 2 V p-p, 25% to 75% 1224 V/μs

O, cm

INPUT CHARACTERISTICS Input Voltage Range 0.5 2.3 V Input Resistance 7.0 8.3 10.2 kΩ Input Offset Voltage V

OS, cm

= V

O, cm

− V

; VIP = VIN = V

OCM

= 0 V −25 +0.35 +15 mV

OCM

Input Voltage Noise f = 100 kHz 23.5 nV/√Hz Gain 0.99 1 1.02 V/V CMRR ΔV

= 1.5 V; RF = RG = 10 kΩ, RL = open circuit −80 −77 dB

OCM

Operating Range 5 V Quiescent Current per Amplifier Enabled 31.1 34 38.4 mA Enabled, T

MIN

to T

variation 74.5

MAX

μA/°C Disabled 0.45 1.8 2.6 mA +PSRR ΔV

−PSRR ΔV

= 1 V; RF = RG = 10 kΩ, RL = open circuit −74 −71 dB

ICM

= 1 V; RF = RG = 10 kΩ, RL = open circuit −91 −75 dB

ICM

Disabled <2.5 V

Enabled >3 V

Enabled Disabled

PD PD

= 5 V = 0 V

0.09 μA 97 μA

Rev. A | Page 6 of 28

ADA4930-1/ADA4930-2

ABSOLUTE MAXIMUM RATINGS

Table 7.

Parameter Rating

Supply Voltage 5.5 V Power Dissipation See Figure 4 Storage Temperature Range −65°C to +125°C Operating Temperature Range −40°C to +105°C Lead Temperature (Soldering, 10 sec) 300°C 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 device (including exposed pad) soldered to a high thermal conductivity 2s2p circuit board, as described in EIA/JESD51-7.

Table 8. Thermal Resistance

Package Type θJA Unit

16-Lead LFCSP (Exposed Pad) 98 °C/W 24-Lead LFCSP (Exposed Pad) 67 °C/W

MAXIMUM POWER DISSIPATION

The maximum safe power dissipation in the ADA4930-1/ADA4930-2 packages is limited by the associated rise in junction temperature (T on the die. At approximately 150°C, which is the glass transition temperature, the plastic changes its properties. Even temporarily exceeding this temperature limit can change the stresses that the package exerts on the die, permanently shifting the parametric performance of the ADA4930-1/ADA4930-2. Exceeding a junction temperature of 150°C for an extended period can result in changes in the silicon devices, potentially causing failure.

)

J

The power dissipated in the package (P quiescent power dissipation and the power dissipated in the package due to the load drive. The quiescent power is the voltage between the supply pins (V

) times the quiescent current (IS).

S

The power dissipated due to the load drive depends upon the particular application. The power due to load drive is calculated by multiplying the load current by the associated voltage drop across the device. RMS voltages and currents must be used in these calculations.

Airflow increases heat dissipation, effectively reducing θ addition, more metal directly in contact with the package leads/ exposed pad from metal traces, through holes, ground, and power planes reduces θ

.

JA

Figure 4 shows the maximum safe power dissipation vs. the ambient temperature for the ADA4930-1 single 16-lead LFCSP (98°C/W) and the ADA4930-2 dual 24-lead LFCSP (67°C/W) on a JEDEC standard 4-layer board.

3.5

3.0

2.5

2.0

1.5

1.0

MAXIMUM POWER DISSIPATION (W)

0.5

0

–40 11090 100

Figure 4. Maximum Power Dissipation vs. Ambient Temperature,

ADA4930-1

–30–20–100 1020304050607080

ADA4930-2

TEMPERATURE (° C)

4-Layer Board

ESD CAUTION

) is the sum of the

D

JA

. In

09209-004

Rev. A | Page 7 of 28

ADA4930-1/ADA4930-2

PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS

S

–V

14

13

15

16

PIN 1 INDICATO R

1–FB

2+IN

ADA4930-1

TOP VIEW

3–IN

(Not to Scale)

4+FB

8

7

5

6

S

+V

NOTES

1. EXPOSED PADDLE. THE EXPOSED PAD IS NO T ELECTRICALLY CONNECTED T O THE DEVI CE. IT I S TYPICALLY SOLDERED T O GROUND OR A POWER

PLANE ON THE PCB THAT IS T HERMALLY CONDUCTIVE.

Figure 5. ADA4930-1 Pin Configuration

12 PD

11 –OUT

10 +OUT

9V

OCM

1

–IN1

2

+FB1

3

+V

S1

4

+V

S1

5

–FB2

6

+IN2

NOTES

1. EXPO SED PADDLE. T HE EXPOSED PAD IS NOT ELECTRICALLY CONNECTED T O THE DEVI CE. IT I S

09209-005

TYPICALLY SOLDERED TO GROUND OR A POWER

PLANE ON THE PCB THAT IS THERMALLY CONDUCTIVE.

Figure 6. ADA4930-2 Pin Configuration

–VS1–VS1–FB1

+IN1

20

21

22

23

24

PIN 1 INDICATOR

ADA4930-2

TOP VIEW

(Not to Scale)

9

7

8

11

10

S2

–IN2

+V

+FB2

V

PD1

–OUT1

19

18

+OUT1

17

V

OCM1

16

–V

S2

–V

15

S2

14

PD2

13

–OUT2

12

OCM2

+OUT2

9209-006

Table 9. ADA4930-1 Pin Function Descriptions

Pin No. Mnemonic Description

1 −FB

Negative Output for Feedback

Component Connection. 2 +IN Positive Input Summing Node. 3 −IN Negative Input Summing Node. 4 +FB

Positive Output for Feedback

Component Connection. 5 to 8 +VS Positive Supply Voltage. 9 V

Output Common-Mode Voltage.

OCM

10 +OUT Positive Output for Load Connection. 11 −OUT Negative Output for Load Connection. 12

PD

Power-Down Pin. 13 to 16 −VS Negative Supply Voltage. EPAD

Exposed Paddle. The exposed pad is not

electrically connected to the device. It is

typically soldered to ground or a power

plane on the PCB that is thermally

conductive.

Table 10. ADA4930-2 Pin Function Descriptions

Pin No. Mnemonic Description

1 −IN1 Negative Input Summing Node 1. 2 +FB1 Positive Output Feedback Pin 1. 3, 4 +V 5 −FB2 6 +IN2 7 −IN2 8 +FB2 9, 10 +V 11 V 12 +OUT2 13 −OUT2 14

Positive Supply Voltage 1.

S1

Negative Output Feedback Pin 2. Positive Input Summing Node 2. Negative Input Summing Node 2. Positive Output Feedback Pin 2.

Positive Supply Voltage 2.

S2

Output Common-Mode Voltage 2.

OCM2

Positive Output 2. Negative Output 2.

PD2

Power-Down Pin 2.

15, 16 −VS2 Negative Supply Voltage 2. 17 V 18 +OUT1 19 −OUT1 20

21, 22 −V 23 −FB1 24 +IN1 EPAD

Output Common-Mode Voltage 1.

OCM1

Positive Output 1. Negative Output 1.

PD1

Negative Supply Voltage 1.

S1

Power-Down Pin 1.

Negative Output Feedback Pin 1. Positive Input Summing Node 1. Exposed Paddle. The exposed pad is

not electrically connected to the device. It is typically soldered to ground or a power plane on the PCB that is thermally conductive.

Rev. A | Page 8 of 28

ADA4930-1/ADA4930-2

TYPICAL PERFORMANCE CHARACTERISTICS

TA = 25°C, VS = 5 V, V

3

VIN = 100mV

0

–3

–6

–9

–12

–15

–18

–21

NORMALIZE D CLOSED LO OP GAIN (dB)

–24

–27

1M 10M 100M 1G 10G

Figure 7. Small Signal Frequency Response

at Gain = 1, Gain = 2, and Gain = 5

3

VIN = 100mV

0

–3

–6

–9

–12

–15

–18

CLOSED LOOP GAIN (dB)

–21

–24

–27

1M 10M 100M 1G 10G

Figure 8. Small Signal Frequency Response

3

VIN = 100mV

0

–3

–6

–9

–12

–15

–18

CLOSED LOOP GAIN (dB)

–21

–24

–27

1M 10M 100M 1G 10G

Figure 9. Small Signal Frequency Response

at T

= −40°C, TA = 25°C, and TA = 105°C

A

= 0.9 V, V

ICM

G = 1, RG = 300 G = 2, RG = 150 G = 5, RG = 60

FREQUENCY (Hz)

VS = 3.3V VS = 5.0V

FREQUENCY (Hz)

= 3.3 V and VS = 5 V

at V

S

TA = –40°C TA = +25°C T

= +105°C

A

FREQUENCY (Hz)

= 0.9 V, R

OCM

= 1 kΩ, unless otherwise noted.

L, dm

9209-007

9209-008

9209-009

3

VIN = 2V p-p

0

–3

–6

–9

–12

–15

–18

–21

NORMALIZED CLOSED LOOP GAIN (dB)

–24

–27

1M 10M 100M 1G 10G

G = 1, RG = 300 G = 2, R

= 150

G

G = 5, RG = 60

FREQUENCY (Hz)

Figure 10. Large Signal Frequency Response

at Gain = 1, Gain = 2, and Gain = 5

6

VIN = 2V p-p

3

0

–3

–6

–9

–12

–15

–18

CLOSED LOOP GAIN (dB)

–21

–24

–27

1M 10M 100M 1G 10G

VS = 3.3V VS = 5.0V

FREQUENCY (Hz)

Figure 11. Large Signal Frequency Response

= 3.3 V and VS = 5 V

at V

S

6

VIN = 2V p-p

3

0

–3

–6

–9

–12

–15

–18

CLOSED LOOP GAIN (dB)

–21

–24

–27

1M 10M 100M 1G 10G

TA = –40°C TA = +25°C T

= +105°C

A

FREQUENCY (Hz)

Figure 12. Large Signal Frequency Response

at T

= −40°C, TA = 25°C, and TA = 105°C

A

9209-010

9209-011

9209-012

Rev. A | Page 9 of 28

ANALOG DEVICES ADA4930-1, ADA4930-2 Service Manual

FEATURES

APPLICATIONS

GENERAL DESCRIPTION

FUNCTIONAL BLOCK DIAGRAMS

TABLE OF CONTENTS

REVISION HISTORY

SPECIFICATIONS

3.3 V OPERATION

3.3 V GENERAL PERFORMANCE

5 V OPERATION

5 V GENERAL PERFORMANCE

ABSOLUTE MAXIMUM RATINGS

THERMAL RESISTANCE

MAXIMUM POWER DISSIPATION

ESD CAUTION

PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS

TYPICAL PERFORMANCE CHARACTERISTICS