Abstract | ||
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Highly efficient switch-mode class-E power amplifiers (PAs) are sensitive to load impedance variations. For voltage standing wave ratios (VSWRs) up to 10:1, the peak switch voltage and the average switch current can increase by a factor of 1.7 and 2.5, respectively, relative to those under nominal load conditions, imposing serious reliability risks. This paper describes a technique to self-protect class-E PAs to decrease their sensitivity to load variations, relying on the tuning of the switch-tank relative-resonance frequency, implemented by an on-chip switched-capacitor bank (SCB). To validate the technique, load-pull measurements are conducted on a class-E PA implemented in a standard 65-nm CMOS technology, employing an off-chip matching network, augmented with a fully automated self-protective control loop. Under nominal conditions, the PA provides 17.8 dBm at 1.4 GHz into
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from a 1.2-V supply with 67% efficiency. The proposed self-protective PA can reduce its peak switch voltage below the technology- and switch design-related limit for any load with a VSWR up to 19:1 while not considerably impacting output power and efficiency, which see a maximum degradation of 1.6 dB and 6%, respectively. Furthermore, a class-E PA designed to safely handle
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the nominal average switch current can reliably operate for VSWRs up to 19:1 when protected with our technique. |
Year | DOI | Venue |
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2020 | 10.1109/TCSI.2019.2926468 | IEEE Transactions on Circuits and Systems I: Regular Papers |
Keywords | Field | DocType |
Switches,Logic gates,Zero voltage switching,Electric breakdown,Degradation,Power generation | Standing wave ratio,Voltage,Standing wave,Electronic engineering,CMOS,Control system,Input impedance,Mathematics,Amplifier | Journal |
Volume | Issue | ISSN |
67 | 2 | 1549-8328 |
Citations | PageRank | References |
0 | 0.34 | 0 |
Authors | ||
5 |
Name | Order | Citations | PageRank |
---|---|---|---|
Jeroen Ponte | 1 | 0 | 0.34 |
Ali Ghahremani | 2 | 1 | 1.42 |
Maikel Huiskamp | 3 | 0 | 0.34 |
Anne Johan Annema | 4 | 24 | 3.53 |
Bram Nauta | 5 | 1770 | 256.74 |