Need a little help on another question folks

[jonobono]

Homework Statement

right I've got a transformer question but I have no clue on what equations it requires.
the circuit. it has a 220 RMS voltage with a dual transformer with 240-0 : 6-0 6-0 written beneath. there is then a combination of 4 diodes and a capacitor of 470uF value. we then have a voltage regulator with reference voltage of 1.25 volts and two resistors, the top one being 130ohms and the bottom being 600 ohms. there is one more capacitor of 47uF and then an 100mA fuse


[ b]2. Homework Equations [/b]
this is why i need your help folks I can't seem to find the equations in the notes i have.

The Attempt at a Solution

im afraid i can't give you answers since I don't have equations. but I am being brutaly honest i need the equations within 4 hours if I am going to get the question done in time.

 

[berkeman]

Homework Statement

right I've got a transformer question but I have no clue on what equations it requires.
the circuit. it has a 220 RMS voltage with a dual transformer with 240-0 : 6-0 6-0 written beneath. there is then a combination of 4 diodes and a capacitor of 470uF value. we then have a voltage regulator with reference voltage of 1.25 volts and two resistors, the top one being 130ohms and the bottom being 600 ohms. there is one more capacitor of 47uF and then an 100mA fuse


[ b]2. Homework Equations [/b]
this is why i need your help folks I can't seem to find the equations in the notes i have.

The Attempt at a Solution

im afraid i can't give you answers since I don't have equations. but I am being brutaly honest i need the equations within 4 hours if I am going to get the question done in time.

Sounds like a standard transformer --> full wave bridge rectifier --> adjustable linear voltage regulator. Here's the LM317 datasheet to get you going:

http://www.national.com/ds/LM/LM117.pdf

.

 

[jonobono]

thanks for the previous help. I've also received extra help from my tutor. however he isn't clear on a couple of the equations as well as me, namely Vripple and the Vref ( he knows it 1+, but doesn't know which way the resistors should be Either Rtop/Rbottom or the other way round. be great if anyone could help within the hour.

Thanks!