ADC for 7-segment

[Alex C.]

Hi,

I have an analog output from an op-amp.
How do I design an ADC so that it will fit in my 7-segment driver to make a
correct display from the 7-segment at the right output voltage fron the
op-amp?

What I understood here is that the 7-segment driver take in 4-bits BCD for
it to display.
Then how do I convert from the input analog voltages to output digital BCD?

What I am trying to construct here is a digital thermometer which use an
op-amp to take the reading of a room temperature.
Temperature varies the output voltage of the op-amp which then needs an ADC
to drive the 7-segment display so that correct temperature reading can be
display on the 7-segment.

Pls advice..

Thanx

Alex

[jsjo...@cc.hut.fi]

In article <01bddfac$c40e91a0$49a5...@kcchong.ime.org.sg>,

A long time ago (when I was about 10) I tried to build a digital thermometer
using a 7107 A/D-converter/7-segment-driver. I don't know whether it is still
manufactured, but it would be perfect for your application.

Johan Sjöholm

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[J. ten Berge]

jsjo...@cc.hut.fi wrote in<6tlj9j$l8g$1...@nnrp1.dejanews.com>...

Yes, it is still manufactured by Intersil. The ICL7107 is for driving
LED-displays, the ICL7106 for LCD.
The chips contain a 3-1/2 digit A/D converter, seven segment decoders,
display drivers, reference voltage generator and a clock. They also have got
an auto-zero and a zero drift of less then 1 microvolt per degree Celsius.
You can use then with a single power supply (7106 only) and require only 7
external passive components and a display.

You could try taking a look at the website of Intersil (if they have one)
for datasheets.

Matthijs.

[Ken]

J. ten Berge wrote:

> Yes, it is still manufactured by Intersil. The ICL7107 is for driving
> LED-displays, the ICL7106 for LCD.
> The chips contain a 3-1/2 digit A/D converter, seven segment decoders,
> display drivers, reference voltage generator and a clock. They also have got
> an auto-zero and a zero drift of less then 1 microvolt per degree Celsius.
> You can use then with a single power supply (7106 only) and require only 7
> external passive components and a display.
>
> You could try taking a look at the website of Intersil (if they have one)
> for datasheets.
>
> Matthijs.

I believe Intersil was bought out by Harris. Harris does have a web sight and
a conciderable amount of data available for these chips.

Ken

[Andy Cleary]

Harris (www.harris.com) makes an IC almost identical to what you specified.
It is an a/d converter and 7 segment decoder in one 40-pin IC. It may even
be the same thing.

-Andy

jsjo...@cc.hut.fi wrote in message <6tlj9j$l8g$1...@nnrp1.dejanews.com>...