Analog Devices AD8352 Service Manual

2 GHz Ultralow Distortion

–

FEATURES

−3 dB bandwidth of 2.2 GHz (AV = 10 dB) Single resistor gain adjust: 3 dB ≤ A Single resistor and capacitor distortion adjust Input resistance: 3 kΩ, independent of gain (A Differential or single-ended input to differential output Low noise input stage: 2.7 nV/√Hz RTI @ AV = 10 dB Low broadband distortion

10 MHz: −86 dBc HD2, −82 dBc HD3 70 MHz: −84 dBc HD2, −82 dBc HD3

190 MHz: −81 dBc HD2, −87 dBc HD3 OIP3 of 41 dBm @ 150 MHz Slew rate: 8 V/ns Fast settling and overdrive recovery of 2 ns Single-supply operation: 3 V to 5.0 V Low power dissipation: 37 mA @ 5 V Power down capability: 5 mA @ 5 V Fabricated using the high speed XFCB3 SiGe process

APPLICATIONS

Differential ADC drivers Single-ended to differential conversion RF/IF gain blocks SAW filter interfacing

≤ 25 dB

V

)

V

Differential RF/IF Amplifier

AD8352

FUNCTIONAL BLOCK DIAGRAM

ENB

RGP

RDP

C

D

R

G

60

–65

–70

–75

–80

HD3 (dBc)

–85

–90

VIP

R

D

VIN

RDN

RGN

BIAS CELL

+

–

AD8352

Figure 1.

VCM VCC

VOP

VON

GND

5728-001

44

42

40

38

36

IP3 (dBm)

34

32

GENERAL DESCRIPTION

The AD8352 is a high performance differential amplifier optimized for RF and IF applications. It achieves better than 80 dB SFDR performance at frequencies up to 200 MHz, and 65 dB beyond 500 MHz, making it an ideal driver for high speed 12-bit to 16-bit analog-to-digital converters (ADCs).

Unlike other wideband differential amplifiers, the AD8352 has buffers that isolate the gain setting resistor (R inputs. As a result, the AD8352 maintains a constant 3 kΩ input resistance for gains of 3 dB to 25 dB, easing matching and input drive requirements. The AD8352 has a nominal 100 Ω differential output resistance.

Rev. A

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.

) from the signal

G

–95

–100

40 60 80 100 120 140 160 180 200

20 220

FREQUENCY (MHz)

Figure 2. IP3 and Third Harmonic Distortion vs. Frequency,

Measured Differentially

The device is optimized for wideband, low distortion performance at frequencies beyond 500 MHz. These attributes, together with its wide gain adjust capability, make this device the amplifier of choice for general-purpose IF and broadband applications where low distortion, noise, and power are critical. In particular, it is ideally suited for driving not only ADCs, but also mixers, pin diode attenuators, SAW filters, and multielement discrete devices. The device is available in a compact 3 mm × 3 mm, 16-lead LFCSP package and operates over a temperature range of −40°C to +85°C.

30

28

05728-002

AD8352

REVISION HISTORY

9/06—Rev. 0 to Rev. A

Changes to Absolute Maximum Ratings....................................... 6

Inserted Figure 10, Figure 11, and Figure 13 ................................ 9

Inserted Figure 17, Figure 18, and Figure 21 ..............................10

Changes to Figure 34...................................................................... 14

Changes to Table 9.......................................................................... 16

Changes to Figure 38...................................................................... 18

Changes to Ordering Guide.......................................................... 19

Gain and Distortion Adjustment (Differential Input) .......... 11

Single-Ended Input Operation ................................................. 12

Narrow-Band, Third-Order Intermodulation Cancellation.13

High Performance ADC Driving ............................................. 14

Layout and Transmission Line Effects..................................... 15

Evaluation Board ............................................................................ 16

Evaluation Board Loading Schemes ........................................ 16

Evaluation Board Schematics ................................................... 17

Outline Dimensions ....................................................................... 19

Ordering Guide .......................................................................... 19

1/06—Revision 0: Initial Version

Rev. A | Page 2 of 20

AD8352

SPECIFICATIONS

VS = 5 V, RL = 200 Ω differential, RG = 118 Ω (AV = 10 dB), f = 100 MHz, T = 25°C; parameters specified differentially (in/out), unless otherwise noted. C

Table 1.

Parameter Conditions Min Typ Max Unit

DYNAMIC PERFORMANCE

−3 dB Bandwidth AV = 6 dB, V A

A

Bandwidth for 0.1 dB Flatness 3 dB ≤ AV ≤ 20 dB, V Bandwidth for 0.2 dB Flatness 3 dB ≤ AV ≤ 20 dB, V Gain Accuracy Using 1% resistor for RG, 0 dB ≤ AV ≤ 20 dB ±1 dB Gain Supply Sensitivity VS ± 5% 0.06 dB/V Gain Temperature Sensitivity −40°C to +85°C 4 mdB/°C Slew Rate RL = 1 kΩ, V

R

Settling Time 2 V step to 1% <2 ns Overdrive Recovery Time VIN = 4 V to 0 V step, V Reverse Isolation (S12) −80 dB

INPUT/OUTPUT CHARACTERISTICS

Common-Mode Nominal VCC/2 V

Voltage Adjustment Range 1.2 to 3.8 V Maximum Output Voltage Swing 1 dB compressed 6 V p-p Output Common-Mode Offset Referenced to VCC/2 −100 +20 mV Output Common-Mode Drift −40°C to +85°C 0.25 mV/°C Output Differential Offset Voltage −20 +20 mV CMRR 57 dB Output Differential Offset Drift −40°C to +85°C 0.15 mV/°C Input Bias Current ±5 μA Input Resistance 3 kΩ Input Capacitance (Single-Ended) 0.9 pF Output Resistance 100 Ω Output Capacitance 3 pF

POWER INTERFACE

Supply Voltage 3 5 5.5 V ENB Threshold 1.5 V ENB Input Bias Current ENB at 3 V 75 nA ENB at 0.6 V −125 μA Quiescent Current ENB at 3 V 35 37 39 mA ENB at 0.6 V 5.3 mA

and RD are selected for differential broadband operation (see Tabl e 5 and Ta b le 6 ).

D

≤ 1.0 V p-p 2500 MHz

OUT

= 10 dB, V

V

= 14 dB, V

V

= 200 Ω, V

L

≤ 1.0 V p-p 2200 MHz

OUT

≤ 1.0 V p-p 1800 MHz

OUT

≤ 1.0 V p-p 190 MHz

OUT

≤ 1.0 V p-p 300 MHz

OUT

= 2 V step 9 V/ns

OUT

= 2 V step 8 V/ns

OUT

≤ ±10 mV <3 ns

OUT

Rev. A | Page 3 of 20

AD8352

NOISE DISTORTION SPECIFICATIONS

VS = 5 V, RL = 200 Ω differential, RG = 118 Ω (AV = 10 dB), V otherwise noted. C

and RD are selected for differential broadband operation (see Tabl e 5 and Ta b le 6 ). See the Applications section for

D

single-ended to differential performance characteristics.

Table 2.

Parameter Conditions Min Typ Max Unit

10 MHz

Second/Third Harmonic Distortion R

1

RL = 1 kΩ, V

= 200 Ω, V

L

OUT

Output Third-Order Intercept RL = 200 Ω, f1 = 9.5 MHz, f2 = 10.5 MHz +38 dBm Third-Order IMD

= 1 kΩ, f1 = 9.5 MHz, f2 = 10.5 MHz,

R

L

= 2 V p-p composite

V

OUT

= 200 Ω, f1 = 9.5 MHz, f2 = 10.5 MHz,

R

L

= 2 V p-p composite

V

OUT

Noise Spectral Density (RTI) +2.7 nV/√Hz 1 dB Compression Point (RTO) +15.7 dBm

70 MHz

Second/Third Harmonic Distortion RL = 1 kΩ, RG = 178 Ω, V R

= 200 Ω, RG = 115 Ω, V

L

Output Third-Order Intercept RL = 200 Ω f1 = 69.5 MHz, f2 = 70.5 MHz +40 dBm Third-Order IMD

= 1 kΩ, f1 = 69.5 MHz, f2 = 70.5 MHz,

R

L

= 2 V p-p composite

V

OUT

= 200 Ω, f1 = 69.5 MHz, f2 = 70.5 MHz,

R

L

V

= 2 V p-p composite

OUT

Noise Spectral Density (RTI) +2.7 nV/√Hz 1 dB Compression Point (RTO) +15.7 dBm

100 MHz

Second/Third Harmonic Distortion RL = 1 kΩ, V R

= 200 Ω, V

L

OUT

Output Third-Order Intercept RL = 200 Ω, f1 = 99.5 MHz, f2 = 100.5 MHz +40 dBm Third-Order IMD

= 1 kΩ, f1 = 99.5 MHz, f2 = 100.5 MHz,

R

L

= 2 V p-p composite

V

OUT

= 200 Ω, f1 = 99.5 MHz, f2 = 100.5 MHz,

R

L

= 2 V p-p composite

V

OUT

Noise Spectral Density (RTI) +2.7 nV/√Hz 1 dB Compression Point (RTO) +15.6 dBm

140 MHz

Second/Third Harmonic Distortion RL = 1 kΩ, V R

= 200 Ω, V

L

OUT

Output Third-Order Intercept RL = 200 Ω, f1 = 139.5 MHz, f2 = 140.5 MHz +41 dBm Third-Order IMD

= 1 kΩ, f1 = 139.5 MHz, f2 = 140.5 MHz,

R

L

= 2 V p-p composite

V

OUT

= 200 Ω, f1 = 139.5 MHz, f2 = 140.5 MHz,

R

L

V

= 2 V p-p composite

OUT

Noise Spectral Density (RTI) +2.7 nV/√Hz 1 dB Compression Point (RTO) +15.5 dBm

= 2 V p-p composite, T = 25°C; parameters specified differentially, unless

OUT

= 2 V p-p −88/−95 dBc

= 2 V p-p −86/−82 dBc

−86 dBc

−81 dBc

= 2 V p-p −83/−84 dBc

OUT

= 2 V p-p −84/−82 dBc

OUT

−91 dBc

−83 dBc

= 2 V p-p −83/−83 dBc

= 2 V p-p −84/−82 dBc

−91 dBc

−84 dBc

= 2 V p-p −83/−82 dBc

= 2 V p-p −82/−84 dBc

−89 dBc

−85 dBc

Rev. A | Page 4 of 20

AD8352

Parameter Conditions Min Typ Max Unit

190 MHz

Second/Third Harmonic Distortion RL = 1 kΩ, V R

= 200 Ω, V

L

Output Third-Order Intercept RL = 200 Ω, f1 = 180.5 MHz, f2 = 190.5 MHz +39 dBm Third-Order IMD

= 1 kΩ, f1 = 180.5 MHz, f2 = 190.5 MHz,

R

L

= 2 V p-p composite

V

OUT

= 200 Ω, f1 = 180.5 MHz, f2 = 190.5 MHz,

R

L

V

= 2 V p-p composite

OUT

Noise Spectral Density (RTI) +2.7 nV/√Hz 1 dB Compression Point (RTO) +15.4 dBm

240 MHz

Second/Third Harmonic Distortion RL = 1 kΩ, V R

= 200 Ω, V

L

Output Third-Order Intercept RL = 200 Ω, f1 = 239.5 MHz, f2 = 240.5 MHz +36 dBm Third-Order IMD

= 1 kΩ, f1 = 239.5 MHz, f2 = 240.5 MHz,

R

L

V

= 2 V p-p composite

OUT

= 200 Ω, f1 = 239.5 MHz, f2 = 240.5 MHz,

R

L

= 2 V p-p composite

V

OUT

Noise Spectral Density (RTI) +2.7 nV/√Hz 1 dB Compression Point (RTO) +15.3 dBm

380 MHz

Second/Third Harmonic Distortion R

2

RL = 1 kΩ, V

= 200 Ω, V

L

Output Third-Order Intercept RL = 200 Ω, f1 = 379.5 MHz, f2 = 380.5 MHz +33 dBm Third-Order IMD

= 1 kΩ, f1 = 379.5 MHz, f2 = 380.5 MHz,

R

L

= 2 V p-p composite

V

OUT

= 200 Ω, f1 = 379.5 MHz, f2 = 380.5 MHz,

R

L

V

= 2 V p-p composite

OUT

Noise Spectral Density (RTI) +2.7 nV/√Hz 1 dB Compression Point (RTO) +14.6 dBm

500 MHz

Second/Third Harmonic Distortion RL = 200 Ω, V Output Third-Order Intercept RL = 200 Ω, f1 = 499.5 MHz, f2 = 500.5 MHz +28 dBm Third-Order IMD

= 200 Ω, f1 = 499.5 MHz, f2 = 500.5 MHz,

R

L

V

= 2 V p-p composite

OUT

Noise Spectral Density (RTI) +2.7 nV/√Hz 1 dB Compression Point (RTO) +13.9 dBm

1

When using the evaluation board at frequencies below 50 MHz, replace the Output Balun T1 with a transformer such as Mini-Circuits® ADT1-1WT to obtain the low

frequency balance required for differential HD2 cancellation.

2

CD and RD can be optimized for broadband operation below 180 MHz. For operation above 300 MHz, CD and RD components are not required.

= 2 V p-p −82/−85 dBc

OUT

= 2 V p-p −81/−87 dBc

OUT

−83 dBc

−81 dBc

= 2 V p-p −82/−76 dBc

OUT

= 2 V p-p −80/−73 dBc

OUT

−85 dBc

−77 dBc

= 2 V p-p −72/−68 dBc

OUT

= 2 V p-p −74/−69 dBc

OUT

−74 dBc

−70 dBc

= 2 V p-p −71/−64 dBc

OUT

−61 dBc

Rev. A | Page 5 of 20

AD8352

ABSOLUTE MAXIMUM RATINGS

Table 3.

Parameter Rating

Supply Voltage VCC 5.5 V VIP, VIN VCC + 0.5 V Internal Power Dissipation 210 mW θ

JA

Maximum Junction Temperature 125°C Operating Temperature Range −40°C to +85°C Storage Temperature Range −65°C to +150°C Lead Temperature (Soldering 60 sec) 300°C

91.4°C/W

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.

ESD CAUTION

Rev. A | Page 6 of 20

Analog Devices AD8352 Service Manual

FEATURES

APPLICATIONS

FUNCTIONAL BLOCK DIAGRAM

GENERAL DESCRIPTION

TABLE OF CONTENTS

REVISION HISTORY

SPECIFICATIONS

NOISE DISTORTION SPECIFICATIONS

ABSOLUTE MAXIMUM RATINGS

ESD CAUTION