ANALOG DEVICES AD8353

1 MHz to 2.7 GHz RF Gain Block AD8353 FEATURES FUNCTIONAL BLOCK DIAGRAM Fixed gain of 20 dB Operational frequency of 1 MHz to 2.7 GHz BIAS AND VREF VPOS Linear output power up to 9 dBm Input/output internally matched to 50 Ω Temperature and power supply stable RFIN RFOUT Noise figure: 5.3 dB Power supply: 3 V or 5 V COM1 COM2 AD8353 APPLICATIONS Figure 1. VCO buffers General Tx/Rx amplification Power amplifier predrivers Low power antenna drivers GENERAL DESCRIPTION The AD8353 is a broadband, fixed-gain, linear amplifier that The noise figure is 5.3 dB at 900 MHz. The reverse isolation operates at frequencies from 1 MHz up to 2.7 GHz. It is (S12) is −36 dB at 900 MHz and −30 dB at 2.7 GHz. intended for use in a wide variety of wireless devices, including The AD8353 can also operate with a 5 V power supply; in cellular, broadband, CATV, and LMDS/MMDS applications. which case, no external inductor is required. Under these By taking advantage of ADI’s high performance, complementary Si conditions, the AD8353 delivers 8 dBm with 20 dB of gain at bipolar process, these gain blocks provide excellent stability 900 MHz. The dc supply current is 42 mA. At 900 MHz, the over process, temperature, and power supply. This amplifier is OIP3 is greater than 22 dBm and is 19 dBm at 2.7 GHz. The noise figure is 5.6 dB at 900 MHz. The reverse isolation (S ) is −35 dB. single-ended and internally matched to 50 Ω with a return loss 12 of greater than 10 dB over the full operating frequency range. The AD8353 is fabricated on ADI’s proprietary, high performance, The AD8353 provides linear output power of 9 dBm with 20 dB 25 GHz, Si complementary, bipolar IC process. The AD8353 is of gain at 900 MHz when biased at 3 V and an external RF available in a chip scale package that uses an exposed paddle for choke is connected between the power supply and the output excellent thermal impedance and low impedance electrical pin. The dc supply current is 42 mA. At 900 MHz, the output connection to ground. It operates over a −40°C to +85°C third-order intercept (OIP3) is greater than 23 dBm and is temperature range, and an evaluation board is also available. 19 dBm at 2.7 GHz. Rev. C 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Fax: 781.461.3113 © 2002–2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 02721-001 AD8353 TABLE OF CONTENTS Features .............................................................................................. 1  Typical Performance Characteristics ..............................................7  Applications ....................................................................................... 1  Theory of Operation ...................................................................... 13  Functional Block Diagram .............................................................. 1  Basic Connections ...................................................................... 13  General Description ......................................................................... 1  Applications Information .............................................................. 14  Revision History ............................................................................... 2  Low Frequency Applications Below 100 MHz ........................... 14  Specif ica t ions ..................................................................................... 3  Evaluation Board ............................................................................ 15  Absolute Maximum Ratings ............................................................ 5  Outline Dimensions ....................................................................... 16  ESD Caution .................................................................................. 5  Ordering Guide .......................................................................... 16  Pin Configuration and Function Descriptions ............................. 6  REVISION HISTORY 3/09—Rev. B to Rev. C 8/05—Rev. 0 to Rev. A Changes to Lead Temperature (Soldering, 60 sec) Parameter, Updated Format .................................................................. Universal Table 3 ................................................................................................ 5 Changes to Product Title .................................................................. 1 Changes to Ordering Guide .......................................................... 16 Changes to Features, Figure 1, and General Description ............. 1 Changes to Table 1 ............................................................................. 3 Changes to Table 2 ............................................................................. 4 12/05—Rev. A to Rev. B Changes to Figure 2 and Table 4 ...................................................... 6 Changes to Table 1 ............................................................................ 3 Changes to Figure 3 caption and Figure 6 caption........................ 7 Changes to Table 2 ............................................................................ 4 Changes to Figure 17 caption and Figure 20 caption ................... 9 Changes to Figure 16 ........................................................................ 9 Changes to Basic Connections Section ....................................... 13 Changes to Figure 32 ...................................................................... 11 Added Low Frequency Applications Below 100 MHz Section 14 Moved Figure 39 to Page 15; Renumbered Sequentially ........... 15 Changes to Table 5 .......................................................................... 15 Changes to Ordering Guide .......................................................... 16 Changes to Ordering Guide .......................................................... 16 Updated Outline Dimensions ....................................................... 16 2/02—Revision 0: Initial Version Rev. C | Page 2 of 16 AD8353 SPECIFICATIONS VS = 3 V, TA = 25°C, 100 nH external inductor between RFOUT and VPOS, ZO = 50 Ω, unless otherwise noted. Table 1. Parameter Conditions Min Typ Max Unit OVERALL FUNCTION Frequency Range 1 2700 MHz Gain f = 900 MHz 19.8 dB f = 1.9 GHz 17.7 dB f = 2.7 GHz 15.6 dB Delta Gain f = 900 MHz, −40°C ≤ T ≤ +85°C −0.97 dB A f = 1.9 GHz, −40°C ≤ T ≤ +85°C −1.15 dB A f = 2.7 GHz, −40°C ≤ T ≤ +85°C −1.34 dB A Gain Supply Sensitivity VPOS ± 10%, f = 900 MHz 0.04 dB/V f = 1.9 GHz −0.004 dB/V f = 2.7 GHz −0.04 dB/V Reverse Isolation (S ) f = 900 MHz −35.6 dB 12 f = 1.9 GHz −34.9 dB f = 2.7 GHz −30.3 dB RF INPUT INTERFACE Pin RFIN Input Return Loss f = 900 MHz 22.3 dB f = 1.9 GHz 20.9 dB f = 2.7 GHz 11.2 dB RF OUTPUT INTERFACE Pin RFOUT Output Compression Point f = 900 MHz, 1 dB compression 9.1 dBm f = 1.9 GHz 8.4 dBm f = 2.7 GHz 7.6 dBm Delta Compression Point f = 900 MHz, −40°C ≤ T ≤ +85°C −1.46 dB A f = 1.9 GHz, −40°C ≤ T ≤ +85°C −1.17 dB A f = 2.7 GHz, −40°C ≤ TA ≤ +85°C −1 dB Output Return Loss f = 900 MHz 26.3 dB f = 1.9 GHz 16.9 dB f = 2.7 GHz 13.3 dB DISTORTION/NOISE Output Third-Order Intercept f = 900 MHz, ∆f = 1 MHz, PIN = −28 dBm 23.6 dBm f = 1.9 GHz, ∆f = 1 MHz, P = −28 dBm 20.8 dBm IN f = 2.7 GHz, ∆f = 1 MHz, P = −28 dBm 19.5 dBm IN Output Second-Order Intercept f = 900 MHz, ∆f = 1 MHz, P = −28 dBm 31.6 dBm IN Noise Figure f = 900 MHz 5.3 dB f = 1.9 GHz 6 dB f = 2.7 GHz 6.8 dB POWER INTERFACE Pin VPOS Supply Voltage 2.7 3 3.3 V Total Supply Current 35 41 48 mA Supply Voltage Sensitivity 15.3 mA/V Temperature Sensitivity −40°C ≤ T ≤ +85°C 60 μA/°C A Rev. C | Page 3 of 16 AD8353 V = 5 V, T = 25°C, no external inductor between RFOUT and VPOS, Z = 50 Ω, unless otherwise noted. S A O Table 2. Parameter Conditions Min Typ Max Unit OVERALL FUNCTION Frequency Range 1 2700 MHz Gain f = 900 MHz 19.5 dB f = 1.9 GHz 17.6 dB f = 2.7 GHz 15.7 dB Delta Gain f = 900 MHz, −40°C ≤ TA ≤ +85°C −0.96 dB f = 1.9 GHz, −40°C ≤ TA ≤ +85°C −1.18 dB f = 2.7 GHz, −40°C ≤ T ≤ +85°C −1.38 dB A Gain Supply Sensitivity VPOS ± 10%, f = 900 MHz 0.09 dB/V f = 1.9 GHz −0.01 dB/V f = 2.7 GHz −0.09 dB/V Reverse Isolation (S12) f = 900 MHz −35.4 dB f = 1.9 GHz −34.6 dB f = 2.7 GHz −30.2 dB RF INPUT INTERFACE Pin RFIN Input Return Loss f = 900 MHz 22.9 dB f = 1.9 GHz 21.7 dB f = 2.7 GHz 11.5 dB RF OUTPUT INTERFACE Pin RFOUT Output Compression Point f = 900 MHz 8.3 dBm f = 1.9 GHz 8.1 dBm f = 2.7 GHz 7.5 dBm Delta Compression Point f = 900 MHz, −40°C ≤ TA ≤ +85°C −1.05 dB f = 1.9 GHz, −40°C ≤ TA ≤ +85°C −1.49 dB f = 2.7 GHz, −40°C ≤ T ≤ +85°C −1.33 dB A Output Return Loss f = 900 MHz 27 dB f = 1.9 GHz 22 dB f = 2.7 GHz 14.3 dB DISTORTION/NOISE Output Third-Order Intercept f = 900 MHz, ∆f = 1 MHz, PIN = −28 dBm 22.8 dBm f = 1.9 GHz, ∆f = 1 MHz, PIN = −28 dBm 20.6 dBm f = 2.7 GHz, ∆f = 1 MHz, PIN = −28 dBm 19.5 dBm Output Second-Order Intercept f = 900 MHz, ∆f = 1 MHz, P = −28 dBm 30.3 dBm IN Noise Figure f = 900 MHz 5.6 dB f = 1.9 GHz 6.3 dB f = 2.7 GHz 7.1 dB POWER INTERFACE Pin VPOS Supply Voltage 4.5 5 5.5 V Total Supply Current 35 42 52 mA Supply Voltage Sensitivity 4.3 mA/V Temperature Sensitivity −40°C ≤ TA ≤ +85°C 45.7 μA/°C Rev. C | Page 4 of 16 AD8353 ABSOLUTE MAXIMUM RATINGS Table 3. Stresses above those listed under Absolute Maximum Ratings Parameter Rating may cause permanent damage to the device. This is a stress Supply Voltage, VPOS 5.5 V rating only; functional operation of the device at these or any Input Power (re: 50 Ω) 10 dBm other conditions above those indicated in the operational Equivalent Voltage 700 mV rms section of this specification is not implied. Exposure to absolute Internal Power Dissipation maximum rating conditions for extended periods may affect Paddle Not Soldered 325 mW device reliability. Paddle Soldered 812 mW θ (Paddle Soldered) 80°C/W JA θ (Paddle Not Soldered) 200°C/W JA ESD CAUTION Maximum Junction Temperature 150°C Operating Temperature Range −40°C to +85°C Storage Temperature Range −65°C to +150°C Lead Temperature (Soldering, 60 sec) AD8353ACP (Non-RoHS Compliant) 240°C AD8353ACPZ (RoHS Compliant) 260°C Rev. C | Page 5 of 16 AD8353 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS COM1 1 8 COM1 AD8353 NC 2 7 RFOUT TOP VIEW RFIN 3 6 VPOS (Not to Scale) 4 5 COM2 COM2 NC = NO CONNECT Figure 2. Pin Configuration Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1, 8 COM1 Device Common. Connect to low impedance ground. 2 NC No Connection. 3 RFIN RF Input Connection. Must be ac-coupled. 4, 5 COM2 Device Common. Connect to low impedance ground. 6 VPOS Positive Supply Voltage. 7 RFOUT RF Output Connection. Must be ac-coupled. Rev. C | Page 6 of 16 04862-002 AD8353 TYPICAL PERFORMANCE CHARACTERISTICS 90 90 120 120 60 60 150 150 30 30 180 180 210 330 210 330 300 300 240 240 270 270 Figure 3. S vs. Frequency, V = 3 V, T = 25°C, dc ≤ f ≤ 3 GHz Figure 6. S vs. Frequency, V = 3 V, T = 25°C, dc ≤ f ≤ 3 GHz 11 S A 22 S A 25 25 GAIN AT 3.3V GAIN AT –40°C 20 20 15 15 GAIN AT +25°C GAIN AT 2.7V GAIN AT +85°C 10 10 GAIN AT 3.0V 5 5 0 0 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 4. Gain vs. Frequency, VS = 2.7 V, 3 V, and 3.3 V, TA = 25°C Figure 7. Gain vs. Frequency, VS = 3 V, TA = −40°C, +25°C, and +85°C 0 0 –5 –5 –10 –10 –15 –15 –20 –20 S AT +25°C 12 –25 –25 S AT 3.0V 12 S AT 2.7V S AT –40°C 12 12 –30 –30 –35 –35 S AT +85°C 12 S AT 3.3V 12 –40 –40 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 5. Reverse Isolation vs. Frequency, VS = 2.7 V, 3 V, and 3.3 V, TA = 25°C Figure 8. Reverse Isolation vs. Frequency, VS = 3 V, TA = −40°C, +25°C, and +85°C Rev. C | Page 7 of 16 GAIN (dB) REVERSE ISOLATION (dB) 02721-003 02721-005 02721-004 GAIN (dB) REVERSE ISOLATION (dB) 02721-006 02721-008 02721-007 AD8353 12 12 P AT –40°C 1dB 10 10 P AT 3.3V 1dB 8 8 P AT +85°C P AT 2.7V 1dB P AT 3.0V 1dB 1dB P AT +25°C 6 6 1dB 4 4 2 2 0 0 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 9. P vs. Frequency, V = 2.7 V, 3 V, and 3.3 V, T = 25°C 1dB S A Figure 12. P1dB vs. Frequency, VS = 3 V, TA = −40°C, +25°C, and +85°C 45 30 40 25 35 30 20 25 15 20 15 10 10 5 5 0 0 19.1 19.5 19.9 20.3 20.7 21.1 21.5 21.9 7.0 7.2 7.4 7.6 7.8 8.0 8.2 8.4 8.6 8.8 9.0 OUTPUT 1dB COMPRESSION POINT (dBm) OIP3 (dBm) Figure 10. Distribution of P , V = 3 V, T = 25°C, f = 2.2 GHz Figure 13. Distribution of OIP3, V = 3 V, T = 25°C, f = 2.2 GHz 1dB S A S A 28 28 26 26 OIP3 AT –40°C 24 24 22 22 OIP3 AT 3.3V 20 20 OIP3 AT +85°C OIP3 AT +25°C 18 18 OIP3 AT 3.0V OIP3 AT 2.7V 16 16 14 14 12 12 10 10 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 11. OIP3 vs. Frequency, V = 2.7 V, 3 V, and 3.3 V, T = 25°C Figure 14. OIP3 vs. Frequency, V = 3 V, T = −40°C, +25°C, and +85°C S A S A Rev. C | Page 8 of 16 P (dBm) OIP3 (dBm) PERCENTAGE (%) 1dB 02721-010 02721-011 02721-009 PERCENTAGE (%) P (dBm) OIP3 (dBm) 1dB 02721-013 02721-014 02721-012 AD8353 8.0 8.5 8.0 7.5 7.5 7.0 7.0 6.5 NF AT +85°C NF AT 3.3V 6.5 6.0 6.0 NF AT +25°C 5.5  5.5 5.0 5.0 NF AT –40°C Ð  NF AT 2.7V NF AT 3.0V 4.5 4.5 4.0 4.0 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 15. Noise Figure vs. Frequency, V = 2.7 V, 3 V, and 3.3 V, T = 25°C Figure 18. Noise Figure vs. Frequency, V = 3 V, T = −40°C, +25°C, and +85°C S A S A 35 50 I AT 3.3V S 45 30 40 I AT 3.0V S 25 35 I AT 2.7V S 30 20 25 15 20 10 15 10 5 5 0 0 5.90 5.95 6.00 6.05 6.10 6.15 6.20 6.25 6.30 6.35 6.40 6.45 6.50 6.55 6.60 –60 –40 –2004 200 60 80 100 NOISE FIGURE (dB) TEMPERATURE (°C) Figure 16. Distribution of Noise Figure, VS = 3 V, TA = 25°C, f = 2.2 GHz Figure 19. Supply Current vs. Temperature, VS = 2.7 V, 3 V, and 3.3 V 90 90 120 120 60 60 150 150 30 30 180 0 180 0 330 210 330 210 300 240 300 240 270 270 Figure 20. S22 vs. Frequency, VS = 5 V, TA = 25°C, dc ≤ f ≤ 3 GHz Figure 17. S11 vs. Frequency, VS = 5 V, TA = 25°C, dc ≤ f ≤ 3 GHz Rev. C | Page 9 of 16 NOISE FIGURE (dBm) PERCENTAGE (%) 02721-017 02721-016 02721-015 SUPPLY CURRENT (mA) NOISE FIGURE (dB) 02721-020 02721-019 02721-018 AD8353 25 25 GAIN AT 5.5V GAIN AT –40°C 20 20 GAIN AT +85°C 15 15 GAIN AT 5.0V GAIN AT 4.5V GAIN AT +25°C 10 10 5 5 0 0 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 24. Gain vs. Frequency, VS = 5 V, TA = −40°C, +25°C, and +85°C Figure 21. Gain vs. Frequency, VS = 4.5 V, 5 V, and 5.5 V, TA = 25°C 0 0 –5 –5 –10 –10 –15 –15 –20 –20 S AT +25°C 12 –25 –25 S AT 5V 12 S AT 5.5V 12 –30 S AT +85°C –30 12 –35 –35 S AT 4.5V S AT –40°C 12 12 –40 –40 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 22. Reverse Isolation vs. Frequency, V = 4.5 V, 5 V, and 5.5 V, T = 25°C Figure 25. Reverse Isolation vs. Frequency, V = 5 V, T = −40°C, +25°C, and +85°C S A S A 10 12 9 P AT 5.5V 1dB P AT +85°C 1dB P AT +25°C 10 1dB 8 7 8 P AT 4.5V 1dB 6 P AT 5.0V 1dB P AT –40°C 1dB 6 5 4 4 3 2 2 1 0 0 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 23. P vs. Frequency, V = 4.5 V, 5 V, and 5.5 V, T = 25°C Figure 26. P1dB vs. Frequency, VS = 5 V, TA = –40°C, +25°C, and +85°C 1dB S A Rev. C | Page 10 of 16 P (dBm) REVERSE ISOLATION (dB) GAIN (dB) 1dB 02721-023 02721-022 02721-021 REVERSE ISOLATION (dB) GAIN (dB) P (dBm) 1dB 02721-026 02721-025 02721-024 AD8353 45 30 40 25 35 30 20 25 15 20 10 15 10 5 5 0 0 18.8 19.2 19.6 20.0 20.4 20.8 21.2 21.6 7.0 7.2 7.4 7.6 7.8 8.0 8.2 8.4 8.6 8.8 OIP3 (dBm) OUTPUT 1dB COMPRESSION POINT (dBm) Figure 27. Distribution of P , V = 3 V, T = 25°C, f = 2.2 GHz Figure 30. Distribution of OIP3, V = 5 V, T = 25°C, f = 2.2 GHz 1dB S A S A 26 26 24 24 OIP3 AT –40°C 22 22 OIP3 AT 5.5V 20 20 18 18 OIP3 AT +25°C OIP3 AT +85°C OIP3 AT 4.5V OIP3 AT 5.0V 16 16 14 14 12 12 10 10 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 28. OIP3 vs. Frequency, VS = 4.5 V, 5 V, and 5.5 V, TA = 27°C Figure 31. OIP3 vs. Frequency, VS = 5 V, TA = –40°C, +25°C, and +85°C 9.0 10 8.5 9 8.0 7.5 8 7.0 NF AT 5.5V 6.5 7 NF AT +85°C 6.0 NF AT 4.5V 6 5.5 NF AT +25°C 5.0 5 NF AT 5.0V 4.5 NF AT –40°C 4.0 4 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 32. Noise Figure vs. Frequency, V = 5 V, T = –40°C, +25°C, and +85°C Figure 29. Noise Figure vs. Frequency, V = 4.5 V, 5 V, and 5.5 V, T = 25°C S A S A Rev. C | Page 11 of 16 NOISE FIGURE (dB) OIP3 (dBm) PERCENTAGE (%) 02721-028 02721-027 02721-029 OIP3 (dBm) PERCENTAGE (%) NOISE FIGURE (dBm) 02721-032 02721-031 02721-030 AD8353 15 20 30 10 19 25 5 18 20 0 17 15 –5 16 10 15 –10 5 14 –15 0 –30 –25 –20 –15 –10 –5 0 5 6.10 6.15 6.20 6.25 6.30 6.35 6.40 6.45 6.50 6.55 6.60 6.65 6.70 P (dBm) IN NOISE FIGURE (dB) Figure 33. Distribution of Noise Figure, VS = 5 V, TA = 25°C, f = 2.2 GHz Figure 35. Output Power and Gain vs. Input Power, VS = 3 V, TA = 25°C, f = 900 MHz 50 15 20 45 I AT 5.5V S 10 19 40 I AT 4.5V S 35 5 18 I AT 5.0V S 30 0 17 25 20 –5 16 15 10 –10 15 5 14 –15 –25 –20 –15 –10 –5 0 5 –30 0 –60 –40 –2004 200 60 80 100 P (dBm) IN TEMPERATURE (°C) Figure 34. Supply Current vs. Temperature, VS = 4.5 V, 5 V, and 5.5 V Figure 36. Output Power and Gain vs. Input Power, VS = 5 V, TA = 25°C, f = 900 MHz Rev. C | Page 12 of 16 SUPPLY CURRENT (mA) PERCENTAGE (%) 02721-033 02721-034 P (dBm) P (dBm) OUT OUT GAIN (dB) GAIN (dB) 02721-036 02721-035 AD8353 THEORY OF OPERATION The AD8353 is a 2-stage, feedback amplifier employing both It is critical to supply very low inductance ground connections shunt-series and shunt-shunt feedback. The first stage is to the ground pins (Pin 1, Pin 4, Pin 5, and Pin 8) as well as to degenerated and resistively loaded and provides approximately the backside exposed paddle. This ensures stable operation. 10 dB of gain. The second stage is a PNP-NPN Darlington The AD8353 is designed to operate over a wide supply voltage output stage, which provides another 10 dB of gain. Series- range, from 2.7 V to 5.5 V. The output of the part, RFOUT, is shunt feedback from the emitter of the output transistor sets the taken directly from the collector of the output amplifier stage. input impedance to 50 Ω over a broad frequency range. Shunt- This node is internally biased to approximately 2.2 V when the shunt feedback from the amplifier output to the input of the supply voltage is 5 V. Consequently, a dc blocking capacitor Darlington stage helps to set the output impedance to 50 Ω. The should be connected between the output pin, RFOUT, and the amplifier can be operated from a 3 V supply by adding a choke load that it drives. The value of this capacitor is not critical, but inductor from the amplifier output to VPOS. Without this it should be 100 pF or larger. choke inductor, operation from a 5 V supply is also possible. When the supply voltage is 3 V, it is recommended that an BASIC CONNECTIONS external RF choke be connected between the supply voltage The AD8353 RF gain block is a fixed gain amplifier with and the output pin, RFOUT. This increases the dc voltage single-ended input and output ports whose impedances are applied to the collector of the output amplifier stage, which nominally equal to 50 Ω over the frequency range 1 MHz to improves performance of the AD8353 to be very similar to the 2.7 GHz. Consequently, it can be directly inserted into a 50 Ω performance produced when 5 V is used for the supply voltage. system with no impedance matching circuitry required. The inductance of the RF choke should be approximately The input and output impedances are sufficiently stable vs. 100 nH, and care should be taken to ensure that the lowest variations in temperature and supply voltage that no impedance series self-resonant frequency of this choke is well above the matching compensation is required. A complete set of maximum frequency of operation for the AD8353. For lower scattering parameters is available at www.analog.com. frequency operation, use a higher value inductor. The input pin (RFIN) is connected directly to the base of the first Bypass the supply voltage input, VPOS, using a large value amplifier stage, which is internally biased to approximately 1 V; capacitance (approximately 0.47 μF or larger) and a smaller, therefore, a dc blocking capacitor should be connected between the high frequency bypass capacitor (approximately 100 pF) source that drives the AD8353 and the input pin, RFIN. physically located close to the VPOS pin. The recommended connections and components are shown in Figure 40. Rev. C | Page 13 of 16 AD8353 APPLICATIONS INFORMATION The AD8353 RF gain block can be used as a general-purpose, LOW FREQUENCY APPLICATIONS BELOW 100 MHz fixed gain amplifier in a wide variety of applications, such as a The AD8353 RF gain block can be used below 100 MHz. To driver for a transmitter power amplifier (see Figure 37). Its accomplish this, the series dc blocking capacitors, C1 and C2, excellent reverse isolation also makes this amplifier suitable for need to be changed to a higher value that is appropriate for the use as a local oscillator buffer amplifier that would drive the desired frequency. C1 and C2 were changed to 0.1 μF to local oscillator port of an upconverter or downconverter mixer accomplish the sweep in Figure 39. (see Figure 38). 21.0 dB-S21 20.5 20.0 HIGH POWER AD8353 19.5 AMPLIFIER Figure 37. AD8353 as a Driver Amplifier 19.0 18.5 MIXER 18.0 17.5 AD8353 17.0 16.5 LOCAL OSCILLATOR 16.0 CH 1: START 300.000kHz STOP 100.000MHz Figure 38. AD8353 as a LO Driver Amplifier Figure 39. Low Frequency Application from 300 kHz to 100 MHz at 5 V VPOS, −12 dBm Input Power Rev. C | Page 14 of 16 04862-038 02721-037 02721-042 AD8353 EVALUATION BOARD Figure 40 shows the schematic of the AD8353 evaluation board. Note that L1 is shown as an optional component that is used to obtain maximum gain only when VP = 3 V. The board is powered by a single supply in the 2.7 V to 5.5 V range. The power supply is decoupled by a 0.47 μF and a 100 pF capacitor. AD8353 1 COM1 COM1 8 C2 1000pF OUTPUT 2 NC RFOUT 7 C1 L1 INPUT 1000pF 3 RFIN VPOS 6 C3 C4 100pF 0.47μF 4 COM2 COM2 5 Figure 41. Silkscreen Top NC = NO CONNECT Figure 40. Evaluation Board Schematic Table 5. Evaluation Board Configuration Options Default Component Function Value C1, C2 AC coupling capacitors. 1000 pF, 0603 C3 High frequency bypass capacitor. 100 pF 0603 C4 Low frequency bypass capacitor. 0.47 μF, 0603 L1 Optional RF choke, used to increase 100 nH, current through output stage when 0603 V = 3 V. Not recommended for use P when VP = 5 V. Figure 42. Component Side Rev. C | Page 15 of 16 02721-039 04862-041 04862-040 AD8353 OUTLINE DIMENSIONS 1.89 3.25 1.74 0.25 3.00 0.55 1.59 0.20 2.75 0.40 0.15 0.30 5 8 1.95 2.25 1.75 TOP VIEW 2.00 EXPOSEDPAD 0.60 0.15 1.55 1.75 BOTTOM VIEW 4 1 0.45 0.10 0.30 0.05 PIN 1 INDICATOR 2.95 0.50 BSC 2.75 2.55 12° MAX 0.80 MAX 1.00 0.65 TYP 0.85 0.80 0.05 MAX 0.02 NOM 0.30 SEATING 0.20 REF 0.23 PLANE 0.18 Figure 43. 8-Lead Lead Frame Chip Scale Package [LFCSP_VD] 2 mm × 3 mm Body, Very Thin, Dual Lead CP-8-1 Dimensions shown in millimeters ORDERING GUIDE Model Temperature Range Package Description Package Option Branding AD8353ACP-R2 −40°C to +85°C 8-Lead LFCSP_VD CP-8-1 JB AD8353ACP-REEL7 −40°C to +85°C 8-Lead LFCSP_VD, 7" Tape and Reel CP-8-1 JB 1 AD8353ACPZ-REEL7 −40°C to +85°C 8-Lead LFCSP_VD, 7" Tape and Reel CP-8-1 0E 1 AD8353-EVALZ Evaluation Board 1 Z = RoHS Compliant Part. © 2002–2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02721-0-3/09(C) Rev. C | Page 16 of 16 031207-A