Possible.  I googled that and didn't see anything other than differentials =
though, with one collector tied high.
It's an odd configuration.

-----Original Message-----
From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf Of=
 Sean Breheny
Sent: Thursday, September 22, 2016 5:44 PM
To: Microcontroller discussion list - Public.
Subject: Re: [EE] Long tailed pair, sort of.

Could it be a two-input inverting summing amplifier? It is too symmetrical =
to be a differential amplifier.

On Tue, Sep 20, 2016 at 12:27 AM, David VanHorn <microbrix@gmail.com> wrote=
:

> It's supposed to be a differential amplifier, but I don't think it's righ=
t.
>
> On Mon, Sep 19, 2016 at 9:30 PM, Jean-Paul Louis <louijp@gmail.com> wrote=
:
>
> > NAND gate using RTL logic?
> >
> > Jean-Paul
> > N1JPL
> >
> >
> > > On Sep 19, 2016, at 6:07 PM, Van Horn, David <david.vanhorn@
> > backcountryaccess.com> wrote:
> > >
> > > I am looking at an amplifier, which is almost a classic long=20
> > > tailed
> pair
> > as figure 2 here:=20
> > https://en.wikipedia.org/wiki/Differential_amplifier
> > >
> > > The difference is that there is only one collector resistor, and=20
> > > both
> > collectors are tied together.
> > > What's up with that?
> > >
> > > I haven't seen that configuration in Horowitz and Hill or Ghausi.
> > >
> > >
> > > --
> > > David VanHorn
> > > Lead Hardware Engineer
> > >
> > > Backcountry Access, Inc.
> > > 2820 Wilderness Pl, Unit H
> > > Boulder, CO  80301 USA
> > > phone: 303-417-1345 x110
> > > email: david.vanhorn@backcountryaccess.com<mailto:david.vanhorn@
> > backcountryaccess.com>
> > >
> > > --
> > > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive=20
> > > View/change your membership options at=20
> > > http://mailman.mit.edu/mailman/listinfo/piclist
> >
> >
> >
> > Just my $0.02,
> >
> > Jean-Paul
> > N1JPL
> >
> >
> >
> >
> > --
> > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive=20
> > View/change your membership options at=20
> > http://mailman.mit.edu/mailman/listinfo/piclist
> >
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive=20
> View/change your membership options at=20
> http://mailman.mit.edu/mailman/listinfo/piclist
>
--
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/chang=
e your membership options at http://mailman.mit.edu/mailman/listinfo/piclis=
t

--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.