Microelectronics Work Shop 23 Development of GaN SSPA for Satellite-Borne Application November 10, 2010 MELOS Mitsubishi Electric TOKKI Systems Corporation Page 1 of 25
Table of Contents 1. The high power amplifier for satellite use 2. GaN device characteristics 3. GaN Device: Achieved Performance 4. GaN SSPA: Achieved Performance 5. Conclusion and Next Target Page 2 of 25
1. High Power Amplifier C-Band Uplink Downlink 6GHz 4GHz Space Segment (Satellite) Telemetry Signals Ku-Band 14GHz 12GHz Uplink Ground Segment Downlink Needs High RF Power Command Signals Control Segment Service Station Interface Station TTC Station Figure 1-1 The present situation of the high power amplifier for satellite use Page 3 of 25
1. High Power Amplifier HPA BCN C O-MUX FEED HYB BCN TC Ch. CA D/C TWT Tx FIL LNA 1:3 CA D/C TWT FEED TC PF TC PF TC PF LNA LNA LNA HYB 1:4 HYB 1:2 HYB Ch. Ch. Ch. CA CA CA CA D/C D/C D/C D/C TWT TWT TWT TWT O-MUX Tx FIL TC LNA 1:4 Ch. CA D/C TWT O-MUX FEED CA D/C TWT Tx FIL TC BCN C Uplink HPAs are applied to each communication channels Applied many HPAs Required Light Weight Small Footprint BCN Downlink Figure 1-2 Typical Communication Subsystem in the Communication Satellite Page 4 of 25
1. High Power Amplifier Equipment of High Power Amplification The following two kinds of hardware take a part of high power amplification. - TWTA: Traveling Wave Tube Amplifier - SSPA: Solid State Power Amplifier TWT EPC EPC Channel Amplifier Main Performance : Main Performance : Frequency: L/S/C Band Output Power:70 to 150 watts Efficiency: 60% Mass: L/S-band : 3400g C-band : 2200g Foot print: 380 cm2 Page 5 of 25 Frequency: L/S/C Band Output Power: L/S-band : 150 watts C-band : 70 watts Efficiency: L/S-band : 55% C-Band : 50% Mass: L/S-band : 1200g C-band: : 1200g Foot print: 200 cm2 HP portion LP portion Figure 1-3a Figure 1-3b
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1. High Power Amplifier Limit of the conventional GaAs SSPA Limit of handling power (25W max) Multiple power combining to achieve higher output power Wider footprint / Heavier mass More Powerful device is desired Page 7 of 25
hhhhgi g i ee g i ffff kkkk hhhhgi g i ee g i ffff kkkk 2. Application of GaN to SSPA 2.1 What will be new and be improved with GaN? Table 2-1 GaAs HEMT and GaN HEMT Frequency Device Type SSPA RF Pout (W) SSPA Efficiency (%) SSPA Power Consumpti on (W) SSPA Heat Dissipation (W) Typical Mass (kg) Figure of Merit 1 Pout/Pdissipatio n (W/W) Figure of Merit 2 Pout/Mass (W/kg) C Band GaAs GaN jjjj ffff / llll mmmm jjjj ffff 40 70 175% 37% 50% 135% 108 140 68 70 1.6 1.2 0.6 1.0 170% 25 58 233% L/S Band GaAs GaN jjjj ffff / llll mmmm jjjj ffff 40 150 375% 39% 55% 141% 103 273 63 123 1.7 1.2 0.6 1.2 191% 24 125 531% Page 8 of 25
" &&&& $ $ $ $ %%%% $ $ $ $!,,,, *+ *+ **** 9999 7777 6666 3333 1111 2222 1111,,,, ----.-.-.-.- 78 6 78 666,,,, *+ *+ **** 1111 ::::! WWWW M [ MMM [[[ dddd ```` [[[[ ZZZZ XXXX YX YX YX YX MMOOMMOO ZZZZ ]^ ]^ ]]]] [[[[ TTTT HHHH GGGG FFFF EEEE ZZZZ XXXX YX YX YX YX WWWW AAYYY Y < AA < < < AAA = = = _ = SSSS ZZZZ ]^ ]^ ]]]] [[[[ TTTT DDDD DDDD CCCC BBBB A AAAA???? < < < < @@@@???? @@@@ AAAA @@@@ JJJJ IIII <<<< ==== >>>>???? @@@@ WWWW RRRR PQ PQ MNO MNO 2.2 Expected GaN SSPA Performance Figure 2-1b Efficiency &&&& )))) '''' (((( 3333 415 415 415 415 / 0,,,, ;;;; " GaN SSPA GaN SSPA 55 <<< < === = >>> >???? @@@ @ AAA aaaa OOOO aaaa b[c b[c b[c b[c SS S S QQ Q Q Figure 2-1a RF Output Power Z Z Z Z \\ \ \ If GaN is applied to the SSPA GaN SSPA Power Efficiency Mass Output L/S-Band: 150 W 55% 1.2 kg A Z Z Z Z \\ \ \ C-Band: 70 W 50% 1.4 kg Figure 2-1c Mass UUUU VVVV ST KKKK LM LM LM LM Page 9 of 25
2.3 Issues to be solved Development of GaN device for space application SQT:Space Qualification Test Applying GaN performance to SSPA design - Thermal performance - Prevent arcing in vacuum environment Radiation effect confirmation Page 10 of 25
3. GaN Device: Achieved Performance 3.1 Device Electrical Performance GaN for space application was developed by Mitsubishi Electric. 55 50 f=3.90ghz f=4.00ghz f=4.10ghz <--Pout 30 25 80 60 f=3.90ghz f=4.00ghz f=4.10ghz <-- PAE 8.0 6.0 Pout (dbm) 45 40 Gp --> 20 15 Gp (db) P.A.E. (%) 40 Ids(RF) --> 4.0 Ids(RF) (A) 35 10 20 2.0 30 20 25 30 35 40 45 Pin (dbm) Figure 3-1a Input to Output Power Figure 3-1b and Gain completion. 5 Page 11 of 25 0 20 25 30 35 40 45 Pin (dbm) I PAE(%) & (A) At device level, RF output power of over 50 dbm (at P2dB) is achieved. Power added efficiency (PAE) exceeds 60 %. 0.0
3.2 Device Qualification Status (1) SQT Summary for GaN device Table 3-1 SQT Result of GaN HEMT Test Condition MIL-STD-750 Group Test Item Results Method Mechanical Test Life Test Temperature Cycling 1051-65/+175 deg.c, 210cycles Shock 2016 1500G, 3 axis Vibration 2051 100-2000 Hz Constant Acceleration 2006 10000 G Seal Test 1071 Gross and Fine leak Internal Visual 2075 SEM 2077 Bond Strength 2037 Die Shear Strength 2017 r/n=0/11 r/n=0/3 RF Life Test 1026 1000 hr r/n=0/2 DC Life Test 1026 1000 hr r/n=0/8 Figure 3-2 MTTF Evaluation 2 test results with Vds=47V are obtained. Expected MTTF = 1.0x10 6 h at T ch =175 degc Test Result with 270 degc, Vds 45V is obtained MTTF with Vds=45 degc :1.3x10 6 hr at T ch =175 degc Page 12 of 25
no s rq tu v p3.2 (2) Arcing Test Results Arcing test was performed with GaN device (100W class). There was no arcing at all from ambient pressure to high vacuum environment. Signal Generator SG 100WClass GaN HPA Test Fixture for Arcing Test Power Monitor Vacuum Chamber Vacuum gauge Figure 3-3 Test Set-up for Arcing Test PM Page 13 of 25 RF output power monitor remains stable during depressurization High Vacuum Figure 3-4 Output Power Monitor
3.3 Device Radiation Hardness Tests (1) Single Event Tests: Radiation hardness test for single event effect (SEB, SEGR) Test condition; - Ion Beam : Br +13 (145MeV) (Br: Bromine) - LET (Liner Energy Transfer): 31.2MeV/(mg/cm 2 ) - Beam fluence : 1x10 6 ions/cm 2 Figure 3-5 Radiation Test Equipment Figure 3-6 GaN Test Fixture Page 14 of 25
3.3 (1) Single Event The device operating condition: Vds=50V,Pout=P13dB Table3-2 RF drive condition & irradiation result no degradation Figure 3-7a Figure 3-7b Figure 3-7c Page 15 of 25
3.3 (2) Total Ionizing Dose Cobalt-60 gamma ray was irradiated on GaN device. 126kGy with RF input, bias Vds=45V,Ids=0.22A No Degradation 86kGy with no RF, pinch-off bias Vds=45V,Vgs=-5V No Degradation Table3-3 Bias condition & irradiation result Figure 3-8a Figure 3-8b Figure 3-8c The Result of Irradiation test after Vd=45V, Id=0.22A operation Page 16 of 25
4. GaN SSPA: : Achieved Performance C-Band SSPA is developed by utilizing GaN device - Single ended configuration for RF portion to minimize size - The EPC (electrical power conditioner) is newly developed to drive GaN drain voltage (35V to 50V) EPC Driver Amp. Performance Summary - Frequency band : 3.95 GHz +/- 150MHz - Output Power: >70 watts - Spurious Output: <-50dBc/Inband - Power consumption: 190 watts (Pout 84W) - Efficiency : 45% - Mass : 1370g - Size : 265 x 95 x 125 High-power Amp. Figure 4-1 GaN C-SSPA Page 17 of 25
4. GaN SSPA: : Achieved Performance Frequency vs. Output Power characteristics 55 The output power achieved 70W Output Power [dbm] 50 45 40 35 Target line:70w 110 30 100 3.7 3.8 3.9 4 4.1 4.2 Frequency [GHz] Figure 4-2 Output Power versus Frequency Characteristics Gain [db] 90 80 70 Linear Gain achieved 100dB 60 3 3.5 4 4.5 5 Frequency [GHz] Figure 4-3 Liner Gain Page 18 of 25
w 4. GaN SSPA: : Achieved Performance CW characteristics Pout>85W PAE>45% at P2dB 50.00 80.00 Output Power [dbm] 45.00 40.00 35.00 45.93dBm=85W -10deg.C +25deg.C +60deg.C Output Power Power Added Efficiency 45 min. 60.00 40.00 20.00 Power Added Efficiency [%] 30.00-25.00-20.00-15.00-10.00-5.00 0.00 5.00 Relative Input Power [db] Figure 4-4 Output Power & Efficiency at CW 0.00 Normalized with 2dB output power compression point (P2dB) Page 19 of 25
} y x y { x { y z x z y x x x z y y ~ 4. GaN SSPA: : Achieved Performance Multi-carrier characteristics Output Power [dbm] 55 50 45 40 35 30 Multi carrier BW=80MHz Tone value:80001-15 -10-5 0 5 Out put Power at Multi carriers Relative Input Power [db] Figure 4-5 Input to Output Power with Multi-Carrier x ~ Noise BW=80MHz Tone value:80001 Ž Œ Š ƒ ƒ ˆ ƒ Figure 4-6 NPR:Noise Power Ratio Page 20 of 25
Thermal Analysis Result 4. GaN SSPA: : Achieved Performance Thermal analysis is performed with the following thermal resistance: - GaN package - Thermal filer (GaN/Chassis) - Chassis - Thermal filer (SSPA/panel) Result: Tj=142.8 deg.c Enough margin to the rated channel temperature of 175 deg.c Figure 4-7 Junction Temperature Page 21 of 25
Qualification Tests 4. GaN SSPA: : Achieved Performance Qualification test was performed successfully based on the following test items and test conditions 1. Thermal Vacuum Test: - Temperature : -10 deg.c to +60 deg.c - Vacuum condition :1x10-6 Torr - Test Cycle : 33 cycle 2. Vibration Test : Pass 3. Mechanical Shock Test : Pass 4. Electro Magnetic Compatibility : MIL-STD 462 applied Table 4-1 Vibration & Shock Test condition Vibration Item Shock Level Remarks Sine 20G all 3axis Random 14.1 Grms X, Y axis 19.7 Grms Z axis 1000G all 3axis Page 22 of 25
5. Conclusion and Next Target 5.1 Achieved Results GaN SSPA was developed and achieve the following performance. GaN device - 100 Watts class GaN is developed - Space Qualification Test is successfully completed - No arcing from ambient pressure to high vacuum environment. - Radiation Hardness is confirmed - No SEB, No SEGR with Vd 50V, P13dB condition - No TID degradation with operation condition (Vd 45V, Id 0.22A) SSPA Performance - 85 Watts RF output power with 45% efficiency is achieved - Single stage configuration, without power combining Slim and light weight is accomplished - Qualification test is successfully completed Page 23 of 25
5.2 Target to Be Improved Power added efficiency will be improved Power Added Efficiency [%] 55 50 45 40 35 30 3.7 3.8 3.9 4 4.1 4.2 Frequency [GHz] Figure 5-1 Efficiency Improvement The total efficiency at normal temperature is 45. EPC have already realized efficiency 94% in other development. Page 24 of 25 QT result EPC efficiency:87% For Next Model EPC efficiency:94% The efficiency in finale stage GaN will be achieved 65% by the improvement of device characteristics improvement. Total efficiency:45% Final Stage GaN efficiency:60% Final Stage GaN efficiency:65% Total efficiency up to 50%
5. Conclusion and Next Target Next Target - Actual operation in the orbit - Development for higher frequency operation depends on the manufacturer Page 25 of 25
End of Presentation Page 26 of 25