Hello Dick and the group,
there are many MOSFET drivers on the market.
Some examples:
Maxim MAX626/627/628 www.maxim-ic.com
International Rectifier IR21xx / IR21xxx www.irf.com
Intersil HIP408x, ICL7667 www.intersil.com
Elantec EL7002/7012/7022 www.???
As Alan mentioned, a dedicated driver IC is not always necessary.
The MOSFET gates can be adequately driven by a simple
complementary transistor buffer unless extremely fast rise/fall
times are required.
Probably my first experimental 137kHz set-up will be something
like the DF3LP "impatient design", simple straight in the old
fashioned way...
It is equally easy to build a "true" class E amplifier which has many
advantages. When properly tuned, it runs amazingly cool and class E
is inherently free from "MOSFET killer" voltage spikes.
The transistor current is very low at the switching instants so the drive
waveform is not very important, it can be quite "non-square" (it should
have 50% duty cycle though). Some HF class E designs even use
sine wave drive! The only downside that I can think of is that the
"transistor utilization factor" is quite low - less output power per
transistor when compared to some other amplifier topologies such
as class D. The reason is simply that the peak drain voltage in a
class E amplifier is almost 4 * supply voltage...
Jim Tonne has written a nice little program for class E design,
CLASSE101.ZIP is available here:
http://www.qsl.net/wb6bld/classe.html
Also, have a look at SOKAL.ZIP on the same page. It contains
a PDF paper with general information about class E. It was
written by Nathan Sokal, "Mr Class E" himself :-)
73
Johan Bodin, SM6LKM
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