🚀 go-pugleaf

In message <3eccb0e6.54530502@News.xtra.co.nz>; Mike Diack wrote:


> I'm redesigning a device for blind navigation that I first designed a
> decade or so ago, which requires a transformer to drive an
> electrostatic transducer (sweeping 100..50KHz, around 100v P/P driven
> from a 6v P/P source).
> My first iteration used a (hand wound) Philips 10mm 3E25 toroid. I
> gave one of my original samples to a local transformer outfit and
> asked them to make me something smaller (and tidier!)
> Everything they came back with was bigger than my original.
> I have seen a polarisation tranny inside an AKG C460 microphone which
> is smaller than the size of a frozen pea. Admittedly this tranny only
> has to handle a single frequency wheras mine carries a sweep, but who
> can make trannies like that or where can the cores be sourced
> (preferably surface mount)

Can't seem to find specifics for audio.

http://www.physics.queensu.ca/wwwhome/assg/tim.htm

"With the onset of miniaturization, many applications in the electronics
industry now require small, low profile components with a high efficiency
of operation. Electromagnetic transformers, having thousands of wire turns
around a ferrite core, have become an obstacle to the progress of
miniaturization, as they are among the most bulky devices on a circuit
board. Piezoelectric transformers have recently received some attention as
a possible alternative. A piezoelectric transformer essentially consists of
two mechanically coupled and electrically insulated piezoelectric
resonators (Fig. 1). When an electrical signal near the frequency of
mechanical resonance is applied to the input section of the transformer,
strong mechanical vibration occurs due to the piezoelectric converse
effect. This vibration is transferred to the output section, inducing a
voltage on its electrodes due to the piezoelectric direct effect, with a
consequent voltage gain. "

OT but cool, a piezo power supply transformer?
http://www.ucop.edu/research/micro/97_98/97_079.pdf



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