H11F1 Analog Fet Optocoupler

[Arthur Harrison]

The H11F1 is an old General Electric part.
You have to be VERY careful about Vds limits to achieve decent
linearity from these devices.  In most cases, they can not substitute
Gilbert core (OTAs), Frey cores (SSM2018s), or photoresistive
technologies, due to severe dynamic range limitations.

One must ask, "99.9% linearity under what conditions?"
Graphs 2 and 5 at http://208.152.152.149/oi/H11FX.pdf
are worth examining carefully.

-Art

-----Original Message-----
From: Edu Silva <edusilva at bahianet.com.br>
To: DIY <synth-diy at mailhost.bpa.nl>
Date: Sunday, December 20, 1998 2:26 PM
Subject: H11F1 Analog Fet Optocoupler


>Hi all!
>
>Has anyone used these chips from QT Technologies? I found it while flipping
>through my Farnell catalog, and it appears very interesting to me.
>
>It's an optocoupler with bilateral analog FET output, designed for
>distortion-free control of low-level AC and DC signals.
>
>Some nice features:
>
>As a remote variable resistor:
>
> <200ohms to >300M
> >99.9% linearity
> 15pf shunt capacitance
> >100G I/O isolation resistance
>
>As an analog switch:
>
> extremely low offset voltage
> 60V pk-pk signal capability
> no charge injection or latchup
> t.on t.off < 25us
>
>It can be used instead of the LED+LDR pair with lots of advantages, like
>faster on/off times, better linearity, and well matched characteristics,
>just to name a few. Not only VCA's and phasers, but any voltage-controlled
>synth module can be built with one or more of these guys!
>
>More info at:
>
>http://www.qtopto.com/oi/o0801.htm
>
>Can any of you give me suggestions/ideas/opinions, etc...?
>
>Cheers,
>Edu
>
>_____________________
>Edu Silva - ES2 Audio
>Salvador-Bahia-Brazil