On Tue, 3 Apr 2007 08:05:22 +0100, "Wombat-Pipex-News"
wrote:


Hi John... agian !! :-)
Ya I'd not mind a little diagram if you have one to hand, but only if you
have it to hand, dont go and spend hours making it just for me mate!
I already had that PDF But just missed that part on page 6 !! Now seing it
again I remember it. :-/ Tipical
I just figured that the ABCD was a streight 0123 connection like on the
CA3161. But didnt think to check first.
Right looks like it needs some pull Up resistors.
Am I right in thinking that I dont realy need those bits in the dotted lined
area, as I don't want the display to show -99
or any over volts anyway. Which I think that part is meant to do. Its for a
Speedo and Tach in a car, so it will only operate in a fixed range anyhow.

---
Right. you can get rid of everything in the dotted lines and also
the two diodes outside of the dotted lines. I don't know what those
black triangles are that connect to the 4012, but you can ignore
them as well.
---

As for the 7 Segment displays, I am using 3 singles like you described. But
looking at the diagram it looks to have 3 buffers (CD4050B) instead.
Why.?

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Dunno. Maybe another mistake?
---

I thought the CA3162E multiplexed the display anyhow using the PNPs.

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It does, and for common cathode displays using a 7447, you'd hook
them up like this:


a----[LED]---+
|
b----[LED]---+
|