http://www.allaboutcircuits.com/vol_4/chpt_13/2.html

Starting from V1 and going through V3, this would give each input voltage exactly half the effect on the output as the voltage before it. In other words, input voltage V1 has a 1:1 effect on the output voltage (gain of 1), while input voltage V2 has half that much effect on the output (a gain of 1/2), and V3 half of that (a gain of 1/4). These ratios are were not arbitrarily chosen: they are the same ratios corresponding to place weights in the binary numeration system. If we drive the inputs of this circuit with digital gates so that each input is either 0 volts or full supply voltage, the output voltage will be an analog representation of the binary value of these three bits.


If we chart the output voltages for all eight combinations of binary bits (000 through 111) input to this circuit, we will get the following progression of voltages:

We can adjust resistors values in this circuit to obtain output voltages directly corresponding to the binary input. For example, by making the feedback resistor 800 Ω instead of 1 kΩ, the DAC will output -1 volt for the binary input 001, -4 volts for the binary input 100, -7 volts for the binary input 111, and so on.

 

The choosing was done in the past, 'were' is correct as it is.

 

The word "were" is more appropriate IMO.

Phrasing the second part to "the resistors" is probably better grammar.

Your feedback is much more readable. Thanks.

 

If you want to add an apostrophe (the resistor's) it would show possession, but I think the best way to go it to make resistors the singular resistor.

 

Disagree on both tracks, in DAC circuits there are almost always multiple resistors, hence the s. There is also multiple values involved. I'm no English teacher, but that is my take.

 

The resistor portion was added after my comment. It makes it hard to follow when you're changing content once the conversation has started.

That said, the resistor wording is off. I would propose:

We can adjust the values of the resistors in this circuit [...]

 

Tshuck's wording is clear and concise, so I thought of not posting.

We can adjust resistors values in this circuit to obtain output voltages directly corresponding to the binary input.

In this sentence, resistor is both possessive and plural. So IMHO, the word should be the resistors'. (And yes, I added the the).

 

It's the way the pluran noun and pronoun are back to back that throws me off for some reason as well as the article the itself. Consider the sentences "the cars' wheels" and "the wheels of the cars". The second sentence refers to a plurality of wheels and a plurality of cars while the second sentence can also be a single individual cars wheels, (if it weren't for the apostrophe after the s in cars'). If spoken verbally the second sentence can take the listener in 2 seperate directions. However, I think wording it in such a way that it will have a precise and precisely understandable meaning both verbally and textually will be the best way to go in the long run. tshucks wording fixes the sentence.