Hello,

I'm using the TI TLV431 in the shunt configuration with two external resistors (see schematic figure link below) to output +2V (vO), and an
Input of +5V. I've determined that the R1/R2 ration needs to be 0.613
(given that VREF=1.24V) for this to happen.

However, I'd like to determine sink resistance (output resistance?) of this circuit but I'm not 100% sure that I'm doing it correctly.

My first take on this is that the output resistance would be determined by shorting the output to ground and determining the short- circuit current (isc), which would be completely driven by the +5V input and the resistor Rin, thus the output resistance being: Rin. Is this the correct approach?

Schematic figure: http://img115.imageshack.us/my.php?image 965654es6.png Datasheet for the TLV431 can be found here: http://focus.ti.com/lit/ds/symlink/tlv431.pdf

Any help would be appreciated.

Thanks!

I'm using the TI TLV431 in the shunt configuration with two external resistors (see schematic figure link below) to output +2V (vO), and an

However, I'd like to determine sink resistance (output resistance?) of this circuit but I'm not 100% sure that I'm doing it correctly.

My first take on this is that the output resistance would be determined by shorting the output to ground and determining the short- circuit current (isc), which would be completely driven by the +5V input and the resistor Rin, thus the output resistance being: Rin. Is this the correct approach?

Schematic figure: http://img115.imageshack.us/my.php?image 965654es6.png Datasheet for the TLV431 can be found here: http://focus.ti.com/lit/ds/symlink/tlv431.pdf

Any help would be appreciated.

Thanks!