B GS 22W2 L10 Per for man ce of D P D T ( Dual -P ole / Dou ble - Th row ) RF M O S s witc h Diff ere nti al LT E, W CD M A, C D MA , U MT S Mo bile Di ve r s ity A ppli c ations Applic atio n N ote A N 308 Revision: Rev. 1.0 2012-11-22 RF and P r otecti on D evic es Edition 2013-06-26 Published by Infineon Technologies AG 81726 Munich, Germany © 2013 Infineon Technologies AG All Rights Reserved. LEGAL DISCLAIMER THE INFORMATION GIVEN IN THIS APPLICATION NOTE IS GIVEN AS A HINT FOR THE IMPLEMENTATION OF THE INFINEON TECHNOLOGIES COMPONENT ONLY AND SHALL NOT BE REGARDED AS ANY DESCRIPTION OR WARRANTY OF A CERTAIN FUNCTIONALITY, CONDITION OR QUALITY OF THE INFINEON TECHNOLOGIES COMPONENT. THE RECIPIENT OF THIS APPLICATION NOTE MUST VERIFY ANY FUNCTION DESCRIBED HEREIN IN THE REAL APPLICATION. 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Last Trademarks Update 2009 10 19 Application Note AN308, Rev. 1.0 3 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications List of Content, Figures and Tables Table of Content 1 Introduction ........................................................................................................................................ 6 2 2.1 2.2 2.3 Features .............................................................................................................................................. 7 Main Features ...................................................................................................................................... 7 Functional Diagram .............................................................................................................................. 7 Signal Description ................................................................................................................................ 8 3 3.1 3.2 3.3 Small Signal Characteristics Measurement Results ...................................................................... 9 Insertion Loss ....................................................................................................................................... 9 Return loss ......................................................................................................................................... 10 Isolation of inactive paths ................................................................................................................... 12 4 4.1 4.2 4.3 Switching time .................................................................................................................................. 14 Measurement Specifications .............................................................................................................. 14 Measurement Setup ........................................................................................................................... 15 Measurement results .......................................................................................................................... 16 5 5.1 5.2 5.3 Intermodulation ................................................................................................................................ 17 Intermodulation test conditions .......................................................................................................... 17 Measurement Setup ........................................................................................................................... 18 Measurement results .......................................................................................................................... 19 6 6.1 6.2 Harmonic Generation ....................................................................................................................... 20 Measurement setup ........................................................................................................................... 20 Measurement results .......................................................................................................................... 21 7 Power Compression Measurements .............................................................................................. 22 8 8.1 8.2 Application Board and Measurement desciption ......................................................................... 23 Application board................................................................................................................................ 23 Measurement description and deembedding ..................................................................................... 24 Author 25 Application Note AN308, Rev. 1.0 4 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications List of Content, Figures and Tables List of Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Differential Band select Switching application ..................................................................................... 6 Functional Diagram .............................................................................................................................. 7 Pin configuration of BGS22W2L10 ...................................................................................................... 8 Forward Transmission curves for all RF paths .................................................................................... 9 Return loss for active port 2 (2P/2N) .................................................................................................. 10 Return loss for active port 3 (3P/3N) .................................................................................................. 11 Isolation of Port 3 (3P/3N) by active Port 2 (2P/2N) .......................................................................... 12 Isolation of Port 2 (2P/2N) by active Port 3 (3P/3N) .......................................................................... 13 Switching Time ................................................................................................................................... 14 Rise/Fall Time .................................................................................................................................... 14 Switching Time Measurement Setup ................................................................................................. 15 Switching Time of BGS22W2L10 ....................................................................................................... 16 Block diagram of RF Switch intermodulation ..................................................................................... 17 Test set-up for IMD Measurements.................................................................................................... 18 Set-up for harmonics measurement ................................................................................................... 20 nd 2 harmonic at fc=824 MHz ............................................................................................................... 21 rd 3 harmonic at fc=824 MHz ................................................................................................................ 21 Power Compression Measurement Results at fc=824 MHz ............................................................... 22 BGS22W2L10 application board ........................................................................................................ 23 Layout of the application board and deembedding kit ....................................................................... 23 PCB layer information ........................................................................................................................ 23 SMA connector for deembedding procedure ..................................................................................... 24 List of Tables Table 1 Table 2 Table 3 Table 4 Table 5 Table 6 Table 7 Table 8 Table 9 Table 10 Table 11 Table 12 Device desciption ................................................................................................................................. 6 Pin Description (top view) .................................................................................................................... 8 Truth table ............................................................................................................................................ 8 Insertion Loss of throw between port1 (1P/1N) and port 2 (2P/2N) ................................................... 10 Insertion Loss of throw between port1 (1P/1N) and port 3 (3P/3N) ................................................... 10 Return loss of all active ports ............................................................................................................. 11 Isolation of Port 3 (3P/3N) by active Port 2 (2P/2N) .......................................................................... 12 Isolation of Port 2 (2P/2N) by active Port 3 (3P/3N) .......................................................................... 13 Switching time measurement results of BGS22W2L10 ..................................................................... 16 Test conditions and specifications of IMD measurements ................................................................. 17 IMD products of Band I ...................................................................................................................... 19 IMD products of Band V ..................................................................................................................... 19 Application Note AN308, Rev. 1.0 5 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Introduction 1 Introduction The BGS22W2L10 RF MOS switch is specifically designed for differential diversity applications (e.g. Figure 1) in low bands up to 2 GHz like 3G WCDMA diversity, CDMA diversity, UMTS diversity or LTE diversity RF frontend system solutions. Therefore, the Insertion loss of the BGS22W2L10 below 1 GHz is closed to 0.2 dB and the port to port Isolation is more than 30 dB. A typical application is to combine two Rx paths in a mobile cellular device after the Rx filters or duplexers into one input to the tranceiver IC. The IC can also be used for a wide variety of applications switching balanced signals in a frequency range of 0.1 - 2 GHz. Diversity Switch B3L Diversity Antenna B7L High Band Low Band B20L B20L Figure 1 Diversity Inputs B1 DPDT B1&B8 DPDT B3L UMTS/LTE Transceiver IC Differential Band select Switching application Unlike GaAs technology, external DC blocking capacitors at the RF Ports are only required if DC voltage is applied externally. The BGS22W2L10 RF Switch is manufactured in Infineon’s patented MOS technology, offering the performance of GaAs with the economy and integration of conventional CMOS including the inherent higher ESD robustness. This DPDT (Dual-Pole / Double Throw) RF MOS switch which combines two differential signals into one differential output or splits one differential signal into two separate differential lines. The parallel paths of the switch are controlled simultaneously through the same signals. The switch is designed to operate in battery powered applications with a supply voltage range of 2.4 - 3.6 V while the current consumption is below 300 μA. The highly symmetric design ensures best phase- and amplitude accuracy. The RF switch is packaged in a standard RoHS compliant TSLP-10-1 package with a small outline of only 1.55 x 1.15 mm². Table 1 Device desciption Product Name Product Type Package Marking BGS22W2L10 DPDT RF Switch TSLP-10-1 W2 Application Note AN308, Rev. 1.0 6 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Features 2 Features 2.1 Main Features 2.2 DPDT (Dual-Pole / Double-Throw) differential RF switch All ports fully symmetrical High ESD robustness Frequency range: 0.1 - 2 GHz High signal power up to 24 dBm Extremely low insertin loss High port-to-port-isolation Supply voltage 2.4 - 3.6 V No decoupling capacitors required if no DC applied on RF lines Lead and halogen free package (RoHS and WEEE compliant) Small leadless package TSLP-10-1 with the size of 1.55 x 1.15 mm² and a maximum height of 0.77 mm. Functional Diagram BGS22W2L10 Port 2P Port 1P Port 3P Port 2N Port 1N Port 3N DPDT ESD Protection VDD Figure 2 VCTRL Functional Diagram Application Note AN308, Rev. 1.0 7 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Features 2.3 Signal Description Table 2 Figure 3 Pin Description (top view) Pin NO Name Pin Type 1 Port 3P I/O Function 2 GND GND Ground 3 GND GND Ground 4 Port 2N I/O RF port 2N 5 Port 2P I/O RF port 2P 6 CTRL I Control Pin 7 Port 1P I/O RF port 1P 8 Port 1N I/O RF port 1N 9 VDD Supply 10 CTRL I RF port 3P Supply voltage Control Pin Pin configuration of BGS22W2L10 Table 3 Truth table Pin No. Control Port1 to Port2 0 Port1 to Port3 1 Application Note AN308, Rev. 1.0 8 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Small Signal Characteristics Measurement Results 3 Small Signal Characteristics Measurement Results All measurement results of this application note are measured with a typical device of the BGS22W2L10 on an application board. The measurement procedure is shown in chapter 0 including the needed deembedding. The small signal characteristics are measured at 25 °C, 0 dBm Pin, 3 Volt Vdd, 3 V Vcrlt up to 10 GHz with a Network analyzer connected to an automatic multiport switch box in single ended mode. A differential simulation is possible ba using a ideal trabnsformator inbetween the Port 1P to 1N, 2P to 2N and 3P to 3N thanks to the full s-Parameter matrix of the BGS22W2L10 which is provided @ Infinieon’s internet page.. In the following tables and graphs the most important RF parameter of the BGS22W2L10 are shown. The markers are set to the most important frequencies of the WCDMA system. 3.1 Insertion Loss Insertion_Loss 10 716 MHz -0.1877 dB 5 824 MHz -0.1981 dB 787 MHz -0.195 dB 885 MHz -0.2015 dB 840 MHz -0.1998 dB 1710 MHz -0.4526 dB 1910 MHz -0.553 dB 0 915 MHz -0.2093 dB -5 1000 MHz -0.2222 dB 960 MHz -0.2102 dB 1N to 2N 1N to 3N 1P to 2P 1P to 3P -10 10 Figure 4 1010 2010 Frequency (MHz) 3010 4000 Forward Transmission curves for all RF paths Application Note AN308, Rev. 1.0 9 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Small Signal Characteristics Measurement Results Table 4 Insertion Loss of throw between port1 (1P/1N) and port 2 (2P/2N) Frequency (MHz) 716 787 824 840 885 915 960 1000 1710 1910 0.19 0.2 0.2 0.21 0.2 0.21 0.2 0.21 0.2 0.21 0.21 0.22 0.21 0.22 0.22 0.23 0.45 0.43 0.55 0.51 RF path 1P 2P 1N 2N Table 5 Insertion Loss of throw between port1 (1P/1N) and port 3 (3P/3N) Frequency (MHz) RF path 1P 3P 1N 3N 3.2 716 787 824 840 885 915 960 1000 1710 1910 0.23 0.21 0.23 0.22 0.24 0.22 0.24 0.23 0.24 0.23 0.24 0.23 0.25 0.24 0.26 0.25 0.47 0.43 0.57 0.53 Return loss Return loss Port1 to Port2 active 0 1910 MHz -11.63 dB -10 -20 1N 2N 1P 2P -30 -40 10 Figure 5 1010 2010 Frequency (MHz) 3010 4000 Return loss for active port 2 (2P/2N) Application Note AN308, Rev. 1.0 10 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Small Signal Characteristics Measurement Results Return loss Port1 to Port3 active 0 1910 MHz -11.47 dB -10 -20 1N 2P 2N 1P -30 -40 10 Figure 6 Table 6 1010 2010 Frequency (MHz) 3010 4000 Return loss for active port 3 (3P/3N) Return loss of all active ports Frequency (MHz) Active Path Throw port 1 to port 2 port 716 787 824 840 885 915 960 1000 1710 1910 1P -25.8 -27.6 -26.5 -28.7 -24.7 -21.1 -26.3 -24.3 -24.2 -25.8 -24.9 -26.8 -19.8 -18.6 -25.3 -23.2 -23.6 -25.1 -24.1 -26.2 -24.2 -20.9 -24.8 -22.7 -23.3 -25.1 -24.1 -26.2 -33 -24.3 -24.5 -22.5 -22.6 -24.1 -23.3 -25.2 -19.8 -17.4 -24.2 -22.3 -22.1 -23.4 -22.6 -24.6 -21.3 -20.3 -24 -22.1 -21.3 -23 -21.9 -24.1 -24.1 -18.5 -23.2 -21.3 -20.6 -22.4 -21.2 -23.3 -18.3 -18.2 -22.7 -21 -12.8 -13.8 -13.1 -14 -14.9 -12.7 -14.4 -13.1 -11.5 -12.5 -11.6 -12.9 -14.7 -13.9 -12.9 -11.8 1N 2P 2N 1P Throw port 1 to port 3 1N 3P 3N Application Note AN308, Rev. 1.0 11 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Small Signal Characteristics Measurement Results 3.3 Isolation of inactive paths Isolation_2N_2P_active 0 1910 MHz -24.48 dB -20 -40 3P to 1P 3N to 1N 3N to 2P 3N to 1P 3P to 2P 3N to 2N 3N to 1N 3P to 2N -60 -80 100 Figure 7 1100 2100 Frequency (MHz) 3100 4000 Isolation of Port 3 (3P/3N) by active Port 2 (2P/2N) Table 7 Isolation of Port 3 (3P/3N) by active Port 2 (2P/2N) Port to port isolation 716 787 824 840 885 915 960 1000 1710 1910 3P 1P -39.5 -44.5 -41.3 -33.9 -44.7 -44 -47.9 -45.5 -38.3 -43.2 -40.3 -33.1 -42.9 -44.2 -47.5 -47.1 -38.3 -42.6 -39.7 -32.6 -43.2 -42.6 -46.2 -43.5 -38.1 -42.7 -39.7 -32.5 -42.6 -42.6 -45.7 -43.2 -37.1 -41.6 -38.8 -31.8 -41.8 -42.6 -45.3 -44.4 -37.1 -41.1 -38.5 -31.6 -41.6 -41.6 -44.9 -42.1 -36.5 -40.7 -37.9 -31 -41.2 -41.7 -43.8 -43.3 -36 -40 -37.6 -30.6 -40.3 -40.4 -43.2 -40.5 -30.2 -32.7 -31.4 -25.1 -33.1 -34.7 -34.6 -33.4 -29.2 -31.3 -30.7 -24.5 -31.7 -32.9 -33.3 -30.7 3N 1P 3P 1N 3N 1N 3P 2P 3P 2N 3N 2P 3N 2N Application Note AN308, Rev. 1.0 12 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Small Signal Characteristics Measurement Results Isolation_3N_3P_active 0 2086 MHz -22.5 dB -20 -40 -60 2P to 1P 3P to 2N 2P to 1N 2N to 1N 3N to 2P 2N to 1P 3P to 2P 3N to 2N -80 10 Figure 8 1010 2010 Frequency (MHz) 3010 4000 Isolation of Port 2 (2P/2N) by active Port 3 (3P/3N) Table 8 Isolation of Port 2 (2P/2N) by active Port 3 (3P/3N) Port to port isolation 716 787 824 840 885 915 960 1000 1710 1910 2P 1P -33.9 -33 -32.6 -32.5 -31.8 -31.5 -31.1 -30.6 -25.1 -23.9 2N 1P -41.5 -40.5 -40.1 -40.1 -39.2 -38.9 -38.5 -37.7 -31.5 -30.1 2P 1N -43.7 -42.4 -42.1 -41.9 -40.9 -40.8 -40 -39.5 -31.7 -29.8 2N 1N -39.3 -38.2 -38.1 -37.8 -37.1 -37 -36.3 -36 -29.8 -28.2 2P 3P 2P 3N -47.8 -49.1 -47.8 -47.9 -45 -46.7 -44.1 -46 -44.5 -46.3 -44.4 -44.9 -42.6 -44.9 -42.9 -43.8 -33.2 -35.2 -31.7 -31.8 2N 3P -46.6 -46.4 -44.9 -44.5 -44.5 -44.1 -43.1 -43.1 -35.3 -34 2N 3N -43.5 -42 -42.2 -41.4 -41.2 -40.8 -40.1 -39.9 -32.5 -30.1 Application Note AN308, Rev. 1.0 13 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Switching time 4 Switching time 4.1 Measurement Specifications Switching On Time: 50% Trigger signal to 90 % RF Signal Switching Off Time: 50% Trigger signal to 10% RF Signal VCTRL 2 VCTRL tON 90% RF signal RF signal tOFF Figure 9 10% RF signal Switching Time Rise time: 10% to 90% RF Signal Fall time: 90% to 10% RF Signal 90% RF signal RF signal tOFF tON Figure 10 10% RF signal Rise/Fall Time Application Note AN308, Rev. 1.0 14 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Switching time 4.2 Measurement Setup Pulse Generator Oscilloscope 1 kHz, 1.8 Volt 50 % Duty Cycle 1 MΩ input VDD = constant, 3Volt Vctrl Vctrl VDD 50 Ω 3P 2P 50 Ω 50 Ω input 50 Ω BGS22W2L10 RFOUT 2N 3P Signal Generator 1N 3 dB 50 Ω 1P RFIN Rf Signal, 1 GHz, +10 dBm 50 Ω output Figure 11 Switching Time Measurement Setup The switching Time measurement setup consist of one pulse generator which generates a sqare wave with 50% duty cycle and an amplitude of 1.8 Volts, an oscilloscope which can detect the 1 GHz signal and the 1 kHz signal and one Signal generator which is set to an output signal of 1GHz with a power level 10 dBm. If the oscilloscope can not detect the 1 GHz signal of the RF path, due to small bandwith, it is possible tu use a cristal oscillator in front of the oscilloscope (such a device detects any RF signal present at input and commutate that one) that the RF signal can be detected. Application Note AN308, Rev. 1.0 15 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Switching time 4.3 Measurement results RF rise time Switching time Figure 12 Table 9 Switching Time of BGS22W2L10 Switching time measurement results of BGS22W2L10 BGS22W2L10 Application Note AN308, Rev. 1.0 RF rise time (ns) Switching time (ns) 263 526 16 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Intermodulation 5 Intermodulation 5.1 Intermodulation test conditions Another very important parameter of a RF switch is the large signal capability. One of the possible intermodulation scenarios is shown in Figure 13.The transmission (Tx) signal from the main antenna is coupled into the diversity antenna with with high power.This signal (20 dBm) and a received Jammer signal (-15 dBm) are entering the switch. Thank to the spezified application for the BGS22W2L10 inbetween the filters and the Transceiver, the Tx signal from the main antenna loose until arriving at the switch input moslty 5 to 10 or more dB, depending of the filter and pcb structure of the RF frontend. The IMD products are measured with a Tx of 20dBm, which is corresponding to the IMD spec of a main antenna diversity switch like Infineons BGSF110GN. Therefore, the measured IMD products will be extremly better in the spezified application circuit within the filters and transceiver as showed in the measurement results below. Coupled Tx Signal from main antenna Jammer (CW) Receiver Diversity Antenna RF Switch IMD Figure 13 Block diagram of RF Switch intermodulation Special combinations of TX and Jammer signal are producing intermodulation products 2 nd and 3rd order, which fall in the RX band and disturb the wanted RX signal. In Table 10 frequencies for 3 bands and the linearity specifications for an undisturbed communication are given. Table 10 Test conditions and specifications of IMD measurements Test Conditions (Tx = +20dBm, Bl = -15dBm,freq.in MHz,@25°C) Band Tx Freq. Rx Freq. IMD2 Low Jammer 1 850 836.5 881.5 45 791.5 1900 1880 1960 80 2100 1950 2140 190 Application Note AN308, Rev. 1.0 Linearity Specification IMD3 IMD2 High Jammer 2 Jammer 3 IM2 (dBm) IIP2 (dBm) IM3 (dBm) IIP3 (dBm) 1718 -105 110 -105 65 1800 3840 -105 110 -105 65 1760 4090 -105 110 -105 65 17 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Intermodulation 5.2 Measurement Setup The test setup for the IMD measurements has to provide a very high isolation between RX and TX signals. As an example the test set-up and the results for the high band are shown (Figure 14 and Table 11). For the RX / TX separation a professional duplexer with 80 dB isolation is used. In Table 12 the results for Low band are given. For each distortion scenario there is a min and a max value given. This variation is caused by a phase shifter connected between switch and duplexer. In the test set-up the phase shifter represents a no ideal matching of the switch to 50 Ohm. Load -20dB -3dB Tx K&L Mini Circuits (ZHL-30W-252 -S+) Signal Generator Power Amplifier Duplexer Tunable Bandpass Filter Circulator DUT ANT Phase Shifter / Delay Line TRx -20dB ANT K&L Tunable Bandpass Filter Signal Generator Rx K& L Signal Analyzer Figure 14 Power reference plane PTx = +20 dBm PBl = -15 dBm -3 dB Tunable Bandpass Filter Test set-up for IMD Measurements Application Note AN308, Rev. 1.0 18 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Intermodulation 5.3 Measurement results Table 11 IMD products of Band I IMD Band 1 1P 2P 1N 2N 1P 3P 1N 3N Min Max Min Max Min Max Min Max IMD2Low (fblocker = 190 MHz) -105.88 -95.29 -104.33 -93.95 -105.80 -94.96 -105.79 -95.60 IMD2High (fblocker = 4090 MHz) -106.28 -102.92 -105.83 -103.77 -105.77 -103.31 -105.44 -102.30 IMD3 (fblocker = 1760 MHz) -108.09 -104.63 -107.52 -104.43 -107.23 -103.79 -107.76 -104.60 Table 12 IMD products of Band V IMD Band 5 1P 2P 1N 2N 1P 3P 1N 3N Min Max Min Max Min Max Min Max IMD2Low (fblocker = 45 MHz) -109.29 -96.58 -102.94 -91.69 -103.49 -92.46 -104.49 -93.77 IMD2High (fblocker = 1718 MHz) -106.50 -101.37 -109.02 -103.90 -107.05 -101.79 -108.59 -103.28 IMD3 (fblocker = 791.5 MHz) -111.09 -107.41 -110.64 -107.35 -110.54 -106.88 -111.98 -107.82 Application Note AN308, Rev. 1.0 19 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Harmonic Generation 6 Harmonic Generation 6.1 Measurement setup Harmonic generation is another important parameter for the characterization of a RF switch. RF switches have in such a Differential Band select Switching application to deal with high RF levels, up to 24 dBm. With this high RF power at the input of the switch harmonics are generated. This harmonics (2 nd rd and 3 ) can disturb the other reception bands or cause distortion in other RF applications (GPS, WLan) within the mobile phone. Load -20dB Directional Coupler -20dB Signal Generator Power Amplifier Circulator Tunable Bandpass Filter A Power meter Agilent E4419B -3dB B DUT ANT K&L Signal Analyzer Figure 15 -20dB Tunable Bandstop Filter Tx Directional Coupler Set-up for harmonics measurement nd rd The results for the harmonic generation at 830 MHZ are shown in Figure 16 (2 harmonic) and Figure 17 (3 harmonic) for all RF ports. At the x-axis the input power is plotted and at the y- axis the generated harmonics in dBm. Application Note AN308, Rev. 1.0 20 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Harmonic Generation 6.2 Measurement results H2 of BGS22W2L10 -60 15 16 17 18 19 20 21 22 23 24 25 -65 1P-->2P -70 1P-->3P -75 1N-->2N -80 1N-->3N -85 Pin (dBm) Figure 16 nd 2 harmonic at fc=824 MHz H3 of BGS22W2L10 -60 15 16 17 18 19 20 21 22 23 24 25 -65 1P-->2P -70 1P-->3P -75 1N-->2N -80 1N-->3N" Pin (dBm) -85 Figure 17 rd 3 harmonic at fc=824 MHz Application Note AN308, Rev. 1.0 21 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Power Compression Measurements 7 Power Compression Measurements To judge the large signal capability the power compression is a usual measurement tool. The input power is increase and at the output the power is measured. At a certain point the output power could not follow the input and the switch compresses the RF signal. In the diagram below (Figure 18) the IL is plotted versus the injected input power. The input power can be increased to 29 dBm and there is no compression visible of the RF port. BGS22W2L10 0.7 Loss (dB) 0.6 0.5 0.4 0.3 IL BGS22W2L10 0.2 0.1 0 Pin (dBm) Figure 18 Power Compression Measurement Results at fc=824 MHz The measurements are done on Large Signal measurement setup which is not calibrated for Insertion Loss with high precision. So the values here may differ with the actual IL values earlier in this report. Application Note AN308, Rev. 1.0 22 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Application Board and Measurement desciption 8 Application Board and Measurement desciption 8.1 Application board Figure 19 BGS22W2L10 application board Figure 20 Layout of the application board and deembedding kit Vias Rodgers , 0.2mm Copper 35µm Figure 21 FR4, 0.8mm PCB layer information Application Note AN308, Rev. 1.0 23 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Application Board and Measurement desciption 8.2 Measurement description and deembedding Below is a picture of the evaluation board used for the measurements (Figure 20). The board is designed in the way that all connecting 50 Ohm lines have the same length. To get correct called “device level” measurement values for the insertion loss of the BGS22W2L10 all influences and losses of the evaluation board, lines and connectors have to be eliminated. Therefore a separate deembedding board, representing the line length is necessary. After full port calibration of the network analyzer (NWA) a deembedding has to be done in severall steps: Attach empty SMA connector (with cutted RF line, Figure 22) at any port of the measurements setup and perform “open” port extension for that one. Turn port extensions on. Connect the “half” de-embedding board (Figure 20, smallest board) between the the port where one of the two RFin port (1P/1N) of the BGS22W2L10 will be connected and the port with the maded port extension, store this as a S-parameter (s2p) file. Turn all port extention off. Load the stored s-parameter file as de-embedding on all used NWA ports Check insertion loss with the de-embedding through board (Figure 20 right upper board) Figure 22 SMA connector for deembedding procedure If the check of the deembedding shows an insertion loss of the through about +- 0.4 dB (depending on the measurement setup accuracy, e.g. NWA) then the Device itself can be measured. Application Note AN308, Rev. 1.0 24 / 26 2012-11-22 BGS22W2L10 Diffential Diversity Applications Author Author André Dewai, Application Engineer of the Business Unit “RF and Protection Devices” Application Note AN308, Rev. 1.0 25 / 26 2012-11-22