[Original question: CCD output buffer; seemed best to make the transistor part a separate post]
Taken from Wikipedia, the circuit in Fig. 1 acts as a common collector (high input impedance - low output impedance, voltage buffer).
In my application, the devices' datasheet (a CCD chip) suggests buffering the output, like in Fig. 2. That is the same as the "classic" CC above, with the notable exception of the 130 Ohm resistor.
What is it used for? The one thing I can think of is to help with biasing, but how will that affect the equations given in Wikipedia?
Bonus question: How much non-linearity can be expected from a CC, roughly speaking?
Let's say the CCD's Vout (before the CC buffer) ranges from 0 - 12V.