Resistor network (SIP)
Four or eight equal resistors in one single in-line package, every one of them between its own pin and a shared common pin.
It is how a row of pull-ups or pull-downs is done in real circuits: one part beside a DIP switch instead of eight loose resistors. Aliases: resistor network, resistor array, SIP resistor, bussed network, 4605, 4609, 10k x 8.
Pins
| Pin | What it does |
|---|---|
C |
The common pin, pin 1, marked with a dot. Every resistor ends here. |
1 to 4 (or 8) |
The other end of each resistor. |
Wire C to the supply and the network is a row of pull-ups; wire it to ground and it
is a row of pull-downs.
Properties
| Property | What it does |
|---|---|
value |
The value of every resistor, in ohms. 10 k by default. |
While it runs
The probe is the total current into the common pin, which is what the rail feeding a row of pull-ups actually supplies.
What the model gets right
It is exactly four or eight resistors joined at one end, so it behaves as they would: pulling one pin to ground moves that pin and no other (the common is held by the supply), and with the common left unconnected one pin's level still reaches the others through two resistors in series, as on a real part. It joins the analog solver the same way a single resistor does.
What it does not model
No tolerance (every resistor is exactly value), no power rating (a real one takes
about an eighth of a watt per resistor), and only the bussed kind: the isolated kind,
whose pins pair up with no common, is not in the bin.
How it looks on the board
A SIP stands upright, so from above it is a thin bar along its own row of holes. That
leaves the rest of each breadboard strip free: plug it in row d alongside a DIP
switch in rows e and f, and each strip has the switch, its pull-up and a hole for
the wire that takes the signal away.
Common mistakes
Putting the common pin (the dotted end) in a signal strip instead of on the supply or ground, so one input becomes the "common" and the others are pulled to it.
See it in action
Switch shifter pulls an 8-way DIP switch up with a 10 k network, and BCD display pulls a 4-way switch down with one. Open them at /templates.