Peak Current, Offset Voltage, Valley Current, RG??

[impaJah]

I've been studying this datasheet for a 2N6027 PUT transistor and I can't deduce with any certainty what these things in the title mean.

http://www.onsemi.com/pub_link/Collateral/2N6027-D.PDF (these terms are on page 3 under the heading "Electrical Characteristics")

So what is Peak Current? Offset Voltage? Valley Current? RG*?

*It is R subscript G. This one is really confusing. It says RG = R1 x R2 / R1 + R2. What does this symbol mean and what does this datasheet mean when it says RG = 2M ohms in the Offset Voltage section?

A big thanks in advance to anyone who can shed some light on this. I'm new to electronics and I find a lot of the terms and symbols that datasheets use are taken for granted which makes them difficult for me to decipher. Google is not much help in this department. Is there some kind of source or reference with common datasheet/electronics lingo that I could refer to in the future instead of having to bother you guys with what are probably really mundane questions?

 

[john monks]

Peak current or Vp is when the voltage first reaches a peak when the current from the anode increases. This occurs when the anode current is 1.25 microamps typical.

Offset voltage (Vt = Vs - Vp). In this Vs is a 10 volt source connected between the cathode and a 1 megohm resistor that is connected to the gate. The Vp is the peak current. In this case the Vt is typically 0.7 volts. That is the Vs is 0.7 volts more than Vp or the peak voltage.

Valley current is Iv. This is the first dip in anode voltage relative to the cathode when the applied current is increasing. In this case the dip in voltage occurs when the anode current is typically at 18 microamps.

Rg is the equivalent Input resistor feeding the gate. This is R1 and R2 in parallel. In this case Rg is 1 megohm.

I fail to see where Rg = 2 megohms on the data sheet. I see 1megohm.

If you do not understand what an uncommon symbol means it's not your fault. It's the author's.
Uncommon symbols need to be clearly defined by the author or they are meaningless. So you should ask what these definitions are if no other reason than to embarrass the author.