egan FET Wireless Energy Transfer Solutions Efficient Power Conversion Corporation

Transcription

1 The egan FET Journey Continues egan FET Wireless Energy Transfer Solutions Efficient Power Conversion Corporation 1

2 Agenda Wireless Power Topologies Overview Wireless Power Results for each Topology Summary 2

3 Overview Output Power < 30 W Loosely coupled, 6.78 MHz (ISM band) based on A4WP standard Topologies Reviewed Class D (Current and Voltage Mode) Class E ZVS Voltage Mode Class D 3 3

4 Wireless Coil-set Overview Simplified representation of coil-set for easy comparison between topologies C devs L devs L src L dev C devp C out R DCload Z load Coil Set 4

5 Experimental Setup Coil Feedback egan FETs RF connection Device Coil Device Board 25mm 50mm Source Board Source Coil RF connection 5

6 Traditional Voltage Mode Class D Switch voltage rating = Supply (V DD ). Level shifting gate driver required. C OSS plays an important role in losses. + V DD Q 2 L mat C s V / I V DD V DS I D Q 1 C mat Z load 50% time Ideal Waveforms 6

7 Voltage Mode Class D Efficiency Efficiency [%] MHz, 23.6 Ω load EPC8004 EPC2014 MOSFET Output Power [W] 7

8 Voltage Mode Class D Load Effect Efficiency [%] MHz, Fixed 14V supply EPC 2014 Efficiency Power DC Load Resistance [Ω] Output Power [W] 8

9 Current Mode Class D EPC2012 has lower FoM than MOSFET C OSS is absorbed into matching network. V DD V / I L CK1 C pt L CK2 + π x V DD L pt V DS I D Q 1 Q 2 C sp Z load 50% time Ideal Waveforms 9 9

10 Current Mode Class D Efficiency Efficiency [%] MHz, 23.6 Ω Load EPC egan FET MOSFET Output Power [W] 10

11 Current Mode Class D Load Effect 78.0 Fixed 5.5 V supply Efficiency [%] EPC 2012 Efficiency Power Output Power [W] DC Load Resistance [Ω] 11

12 Class E Overview Switch voltage rating = > 3.56 Supply (V DD ). C OSS absorbed into matching network. V DD V / I + L RFck L e C s 3.56 x V DD V DS Q 1 C sh I D Z load 50% Ideal Waveforms time 12

13 Class E Efficiency as Function of Load Efficiency [%] 6.78 MHz, 20.5 Ω Load EPC Output Power [W] egan FET MOSFET 13

14 Class E Load Effect 6.78 MHz, Fixed 20 V supply Efficiency [%] Efficiency EPC 2012 Power Output Power [W] DC Load Resistance [Ω] 14

15 Class E Thermal Performance NO HEAT-SINK 30 W, 20.2 Ω Load LM5113TM EPC

16 Class E egan FET vs. MOSFET P FET [mw] Total FET Power losses FDMC86248 EPC Load Power [W] 16

17 ZVS Voltage Mode Class D C OSS Voltage is transitioned by the ZVS tank Lower egan FET C OSS leads to higher available duty cycle Highest system efficiency Q 1 C sp + V DD V / I V DD L m V DS I D Q 2 C m Z load ZVS tank 50% time Ideal Waveforms 17

18 ZVS Voltage Mode Class D Efficiency Efficiency [%] EPC Ω load 23.6 Ω load Output Power [W] 18

19 ZVS Voltage Mode Class D Load Effect 81 Fixed 26 V supply Efficiency [%] EPC 2007 Efficiency Power Output Power [W] DC Load Resistance [Ω]

20 ZVS Class D Thermal Performance NO HEAT-SINK R DCLoad = 35 Ω, V in = 42 V, P out = 35 W, f = 6.78 MHz LM5113TM EPC

21 ZVS Class D FoM Comparison FOM [nc mω] EPC2007 Q OSS R DS(on) Qoss RDS(on) QG RDS(on) Q G R DS(on) BV DSS = 100 V Q OSS = 8.9 nc at 40 V Q G = 2.1 nc at 5 V R DS(on) = 24 mω FDMC8622 BV DSS = 100 V Q OSS = 7.3 nc at 40 V Q G = 5.2 nc at 10 V R DS(on) = 43.7 mω 21

22 ZVS Class D egan FET vs. MOSFET P FET [mw] Total FET Power losses FDMC EPC Load Power [W] 22

23 Summary of Efficiency Results Efficiency [%] MHz, 23.6 Ω Load, egan FET EPC 2014 EPC Output Power [W] EPC 2012 EPC 2007 ZVS-CD SE-CE CM-CD VM-CD 23

24 Simulated FET Losses All Topologies Per FET Power loss [mw] 800 Exceeds thermal capability of FET Fixed Supply Voltage W ZVS-CD SE-CE CM-CD VM-CD DC Load Resistance [Ω] 24

25 Summary Wireless Power Transmission is one of the largest potential markets for power transistors. ZVS Class D shows great promise for a simple, low cost, and high efficiency topology for wireless power. egan FETs enable greater duty cycle and higher efficiency. egan FETs enable the highest efficiency in all topologies using 6.78 MHz and MHz frequencies. egan technology is disruptive. 25

26 The end of the road for silicon.. is the beginning of the egan FET journey! 26