Take a look at National. I think they call I2C protocol "microwire".
They make NICE stuff, and its affordable.

--Bob

Anthony Van Herrewege wrote:

>Hi,
>=20
>I want to make an circuit to measure angles, both for myself, just to se=
e if I can and also because I'll probably be able to use it in an assignm=
ent for university later this year.
>=20
>Since I want to be able to measure up to 1mV precise and the system will=
 be working on 5V, I need at least 13 bit of resolution (right?). To meas=
ure angles I'll be using an accelerometer, a dual-axis one, so that I can=
 measure any angle from 0 to 360 degrees with good accuracy (the accuracy=
 using only a single axis one isn't that good anymore once you reach +- 6=
0 degrees). So I need 2 A/D channels. The maximum output of the accelerom=
eter shouldn't be higher than 4V.
>=20
>Also, I'd like I=B2C for data transfer, since the sensor needs to be as =
small as possible and thus I'll have a separate board for a =B5C and poss=
ibly other circuitry. The only things on the sensor PCB will be the accel=
erometer, an LDO linear voltage regulator and the A/D converter(s). So, b=
ecause of that I can't have a 48LCC A/D converter on the board, it would =
make it way too big. (Everything will be SMD of course.)
>=20
>I've been spending the last 2 hours searching sites of big manufacturers=
 for that kind of A/D converter and the only good ones I've found are the=
 Maxim MAX1069 (14-bits) and MAX1169 (16-bits), but they've only got 1 ch=
annel. There's also the Maxim DS2450, which is 16-bits, but starting at o=
nly 9-bits, the accuracy is lower than the resolution. I also found the T=
I ADS1112, which is very nice, being in a SOP6 package and all, but it on=
ly supports input voltages up to 2.046 (or something like that).
>=20
>So, I was wondering if anyone knew of any small (16SOIC is not small), a=
t least 13-bits, preferably 2 channels (but 1 is OK if it's a SOP6 packag=
e for example), I=B2C (or 1-wire, but rather not) A/D converter?
>=20
>Oh, sample rate isn't very important, as long as I can aqcuire more than=
 60 samples/second that should be fine, I'm measuring tilt after all, so =
changes pretty slow.
>=20
>Or are my demands just too high?
>=20
>Thanks, Anthony Van Herrewege
>
>
>Website: http://members.lycos.nl/anthonyvh
>
>	=09
>---------------------------------
>Do you Yahoo!?
> Meet the all-new My Yahoo! =96 Try it today!=20
> =20
>


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