The simplistic Salas low voltage shunt regulator

[jameshillj]

Thanks, will do.

[pedefede]

I am building a disco 1,2V for DAC

- would you also recommend 2SK117 here (instead of 2sk170) as in bib??
- what mA should i aim at, for the idss at Q5 in error-circuit? (low as possible?)

peter

[Salas]

They can be used also but be GR. Q5 lowest IDSS in your batch, yes.

[pedefede]

sourcing components...

What would make a good resistor for psu (used for DAC)
1) smd ? (for short signalpath)
2) nonmagnetic ?
3) noninductive, noncapacitive ?
4) Else?

[Salas]

Low ppm.

[merlin el mago]

Low TCR

[RCruz]

What is TCR ?

[pedefede]

Originally Posted by Salas

Low ppm.

low ppm prevents drift of V-out, with rising temperature. But does it benifit performance (noise, Zo etc) in any other way?

[RCruz]

Originally Posted by RCruz

What is TCR ?

Temperature Coefficient of Resistance (TCR) is expressed as the change in resistance in ppm ( .0001%) with each degree of change in temperature Celsius (Co). This change is not linear with the TCR the lowest at +25oC and increasing as the temperature increases ( or decreases). It can be either a bell shaped curve or an S shaped curve. It is treated as being linear unless very accurate measurements are needed, then a temperature correction chart is used. Normally a resistor with a TCR of 100 ppm will change 0.1% over a 10 degree change and 1% over a 100 degree change. The expression of ppm , one part in a million is similar to percent or 1 part in 100 (or percentile)

[merlin el mago]

Originally Posted by RCruz

Temperature Coefficient of Resistance (TCR) is expressed as the change in resistance in ppm ( .0001%) with each degree of change in temperature Celsius (Co). This change is not linear with the TCR the lowest at +25oC and increasing as the temperature increases ( or decreases). It can be either a bell shaped curve or an S shaped curve. It is treated as being linear unless very accurate measurements are needed, then a temperature correction chart is used. Normally a resistor with a TCR of 100 ppm will change 0.1% over a 10 degree change and 1% over a 100 degree change. The expression of ppm , one part in a million is similar to percent or 1 part in 100 (or percentile)