You could try something like this.I didn't build it but looks good on sim.
Mona
Attachments
3 terminal devices can be exceptional, particularly as current sources
don't disregard them.
Cheers / Chris
Being a feedback amplifier, a certain amount of capacitance on the output is necessary in practice, to ensure stability.
Not with every circuit, and if possible avoid capacitors directly on outputs.
In my humble experience using cap multipliers in prior stages is the correct way
to apply capacitance in power supplies.
Cheers / chris
Attached diagram shows 7805 and LM317 as current regulators
in each case formula is Vref / R, shown on page 20 of the LM317 datasheet
http://www.ti.com/lit/ds/symlink/lm117.pdf
Looks like the LM317 has received an update to its application data too, now
with suggested layout's.
Cheers / Chris
I would be VERY interested in a regulator that is stable without output cap. I think it would qualify for a very attractive patent! It's the holy grail many companies have been searching for. So far they haven't got any further than a minimum output cap with low ESR.
So if you have it, let's have it Chris!
Jan
Hi Jan
78x series regulators to quote National Semiconductor
http://www.biltek.tubitak.gov.tr/gelisim/elektronik/dosyalar/30/LM7805.pdf
"It is not necessary to bypass the out- put, although this does
improve transient response. Input by-passing is needed only
if the regulator is located far from the filter capacitor of the power supply"
and under Features
No external components required
Why this is so, is because the output is coupled internally to the ground pin
typically with ST brand for a 7805 at 5k for a TO220 package, and 4,3k for a TO92
and 12k to 15k for a 7812. So rule of thumb about 1k for every volt of regulated voltage
is internal bypassing, making output capacitors for the most part unnecessary.
Cheers / Chris
78x series regulators to quote National Semiconductor
http://www.biltek.tubitak.gov.tr/gelisim/elektronik/dosyalar/30/LM7805.pdf
"It is not necessary to bypass the out- put, although this does
improve transient response. Input by-passing is needed only
if the regulator is located far from the filter capacitor of the power supply"
and under Features
No external components required
Why this is so, is because the output is coupled internally to the ground pin
typically with ST brand for a 7805 at 5k for a TO220 package, and 4,3k for a TO92
and 12k to 15k for a 7812. So rule of thumb about 1k for every volt of regulated voltage
is internal bypassing, making output capacitors for the most part unnecessary.
Cheers / Chris
I can contribute this compound BJT double polarity circuit. Classic series pass topology. Its output will be 0.6V lower than any chosen Zener value. It likes no less than 5V Vin>Vout to perform well and its JFETs should not have more than 2.5V VGS (OFF). For your 0.1A load current two very small clip on sinks will be plenty for the MJE pass transistors.
Attachments
If you want discrete, the good old Pooge are still a safe bet:
http://www.diyaudio.com/forums/solid-state/5336-voltage-regulators-line-level-circuits.html
http://www.diyaudio.com/forums/solid-state/5336-voltage-regulators-line-level-circuits.html
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