X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f
X-Recipient: geda-user AT delorie DOT com
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII;
 format=flowed
Content-Transfer-Encoding: 7bit
Date: Fri, 16 Feb 2018 16:10:36 +0100
From: mhx AT iae DOT nl
To: geda-user AT delorie DOT com
Subject: Re: [geda-user] (Off-topic) Question wrt driving HV piezo transducer
In-Reply-To: <1a5665d2-c032-29f3-6de3-d4e3cd52f42b@linetec.nl>
References: <c3aa1897-3806-3f72-feef-85551a63c2db AT linetec DOT nl>
 <alpine DOT DEB DOT 2 DOT 00 DOT 1802091235090 DOT 12270 AT igor2priv>
 <6221de93-bb98-d397-79b4-eecf3975c2e6 AT linetec DOT nl>
 <alpine DOT DEB DOT 2 DOT 00 DOT 1802091324350 DOT 12270 AT igor2priv>
 <f2259553-7015-8fc8-33b2-8ca8be6c5a45 AT linetec DOT nl>
 <alpine DOT DEB DOT 2 DOT 00 DOT 1802091427450 DOT 12270 AT igor2priv>
 <20180209161532 DOT 6AF57804CEFA AT turkos DOT aspodata DOT se>
 <alpine DOT DEB DOT 2 DOT 00 DOT 1802091735590 DOT 12270 AT igor2priv>
 <20180209204934 DOT CAA35804CEFA AT turkos DOT aspodata DOT se>
 <alpine DOT DEB DOT 2 DOT 00 DOT 1802100406500 DOT 12270 AT igor2priv>
 <b125c1d5-48a1-c1dc-3ee1-db9875d50bf6 AT linetec DOT nl>
 <c49d734f1b1f6373733e6f9935afff35 AT iae DOT nl>
 <da435a2d-0bd0-f6d7-7d9a-05394665621c AT linetec DOT nl>
 <aeedf5b6a230f39abdc82845a57a8b1b AT iae DOT nl>
 <1a5665d2-c032-29f3-6de3-d4e3cd52f42b AT linetec DOT nl>
Message-ID: <8a6378847926baf01ef4fca1383d2bb9@iae.nl>
X-Sender: mhx AT iae DOT nl
User-Agent: Roundcube Webmail/1.2.4
ClaraMail2-Webmail-AuthUser: mhx AT iae DOT nl
Reply-To: geda-user AT delorie DOT com
Errors-To: nobody AT delorie DOT com
X-Mailing-List: geda-user AT delorie DOT com
X-Unsubscribes-To: listserv AT delorie DOT com
Precedence: bulk

On 2018-02-16 12:38, Richard Rasker (rasker AT linetec DOT nl) [via 
geda-user AT delorie DOT com] wrote:
> Hello Marcel,
> 
> Op 16-02-18 om 06:32 schreef mhx AT iae DOT nl:
>> On 2018-02-15 23:02, Richard Rasker (rasker AT linetec DOT nl) [via 
>> geda-user AT delorie DOT com] wrote:
[..]
> For all clarity, I attached the schematic, also because there's
> something else I don't understand: the top MOSFET (Q1) doesn't get the
> burst frequency at all, just the 1.5 ms LF pulses. The bottom one (Q2)
> is supplied with the burst signal as expected.

That must indeed be wrong. But there is something else, the top and 
bottom driver
want 180 degrees out of phase signals. An inverter seems to be missing, 
or
the two exors are wired differently than you think?
[https://wwwee.ee.bgu.ac.il/~pemic/publications/jour3.pdf]

> I carefully checked this against the schematic I was given, and I'm
> positive that I didn't make a mistake here. Could this be a mistake on
> behalf of the original designer? I contacted the supplier, but they
> couldn't tell me anything. Or perhaps Q1 is 'automatically' syncing to
> Q2 via changing voltage levels on the drain? I can't really see this
> happening in any reliable way...

No, this looks like a push-pull allright. Are those two 1uF caps not 
connected
to the center tap? The electrolytic 4700uF might not like the very large 
AC ripple.

> BTW, the circuit isn't really designed for resonance, as the 41 kHz
> given is in reality a selectable frequency between 3 kHz and 300 kHz,
> with 41 kHz being just one of the settings.

That is certainly going to blow when built like this, then. To make it 
work
between 3 and 300 kHz should be impossible. With that specification 
you'll want a
linear amplifier. With a dutycycle of 1.5ms/10s = 1:6666, dissipation is
not the issue, when the SOAR of the devices is respected.

[..]

-marcel