Two questions: I thought that a resistor network/array was just a combination of resistors together. Is there anything more to it? This question distinguished a resistor network vs a bunch of discrete resistors: Pros and cons of using resistor networks over individual resistors?
Why don't you combine all the resistors together into one resistor?
One common use of a resistor network is to pull multiple lines up or down, e.g. on a data bus:
simulate this circuit – Schematic created using CircuitLab
Replacing the resistor network with a single resistor would short all of the lines in the bus together, making it not work at all:
For long run machine assembly placement of a component costs 3-4 cents. A resistor and an array cost sub cent. So one network saves about 10 cents. It may become difference of tens of thousands of dollars for serial production.
The main advantage of resistor networks is space and time. When using the same value resistor multiple times, as in pull up resistors on a micro processor buss. Placing 1 component that has say 8 resistors in it with no space between them,it saves space and also saves the effort of placing multiple components with just 1. They are never connected together except on one side, to go to Gnd for pull down or Vcc for pull up. The other type does not connect the resistors at all, for address lines that need series resistors for example.
