General > General Technical Chat
2-pads printer ink chip?
(1/1)
bitwelder:
I was recently replacing the toner cartridge of my Oki laser printer.

Looking at the 'smart' ink chip on it, it's a 6-pins SMD chip (SOIC-6 perhaps?) with only 2 pins connected
to external pads on the tiny PCB.

With only 2 terminals, how does in general such a chip work?
Is the exchanged data encoded in the supply voltage, or does it communicate
in some other way, e.g. a Hall (or other magnetic field) sensor?
ebastler:
One solution is commercially available as "1-Wire", by Dallas Semiconductor.
https://en.wikipedia.org/wiki/1-Wire

It charges a capacitor to buffer the supply voltage while serial data communications are underway.
daqq:
There are a few standards that allow communication and power over a single wire + GND. 1 Wire or the Microchip standard:
http://ww1.microchip.com/downloads/en/DeviceDoc/AT21CS01-AT21CS11-Data-Sheet-DS20005857D.pdf

There are actually crypto authentication devices that enable single wire communication, can't remember which devices, designed precisely for this situation.
Navigation
Message Index
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod