Going Linear with the Caiman

[Reid Malenfant]

Ah, I see. I'm not 100% sure on the Caiman's current consumption but I don't think it's more than 2.5A. So what would you recommend for that?

While we're on the subject, what type of diodes/bridge rectifier would you recommend for use in a SuperTeddy reg based supply?

Thanks.

2.5A i'd recommend a 1N5820 or 5821/5822, the only difference is breakdown voltage. The 1N5820 being 20V, 21 being 30V & 22 40V. As it's forward biased then toss a coin for it

I'm not sure what the SuperTeddy current output is & a brief look at the link gave no clues. Obviously current capacity & voltage breakdown are going to be important. Let me know what the main rectifier has to deal with & i'll be able to put you in the picture.

You can always overate the diodes, i always do & this results in less voltage drop as well as being overkill & effectively lasting probably longer than any other component

As an example i wanted a load of schottkys that would be happy with a continuous current of 11Amps or so but at low voltage. I happened to find a load of 15V devices ( i needed 10V max) & each one was rated 100A. They'll last forever

[Reid Malenfant]

150mA .

Ok then, a 1N5819 will suffice

[HighFidelityGuy]

Awesome, thanks Mark.

The SupperTeddy has a maximum output current of 1A as standard I believe. 2A can be achieved with upgraded jfets. I'm using a 24V toroidal transformer. Does that help you to figure out what diodes would be best for this?

Thanks.

[Reid Malenfant]

Use the previously mentioned 1N5822 40V 3Amp..

These will handle 3A continuous DC (over 10Amp peak pulsed @ 50Hz) & have a maximum reverse voltage of 40V. However, they do have rather thick leads to the diode & i'm guessing that these help conduct heat to the circuit board to help dissipate heat. You could always upgrade to a higher current schottky such as the type mounted in a TO220 type transistor case & carefully bend the legs to fit.

It's what i'd do

I'll be back tomorrow if you have any more questions, feel free, it's what its all about

Bests to you... drinkinone.gif

[MartinT]

Hi Mark, I'm feeding my SuperTeddy from a standard bridge rectifier (inline four pinout). Are there any fast switching low noise bridges in existence, do you know?

[leo]

Not tried any of these myself yet http://www.partsconnexion.com/rectifier_bridge_hex.html

I'm currently trying some Cree Silicon Carbides (but as discrete) in another dac. Its quite surprising the effect you can get playing about with the rectifiers

For the Caiman I'm just going to try running the supply after the input DC diode just to see, for the STR I just use a rectifier made from UF4002

[MartinT]

Thanks, Leo. Never seen a bridge rectifier with 5 legs before! I will check the pinout but may make up my own with four hexfred diodes.

[Ali Tait]

I was going to suggest making your own,it's easy to do.

[Reid Malenfant]

Hi Mark, I'm feeding my SuperTeddy from a standard bridge rectifier (inline four pinout). Are there any fast switching low noise bridges in existence, do you know?

Well i do now that Leo has linked to some

Offhand no i don't, but as Ali says they are easy enough to make & then you'll have a much wider choice of diode types to play with

[HighFidelityGuy]

Not tried any of these myself yet http://www.partsconnexion.com/rectifier_bridge_hex.html

I'm currently trying some Cree Silicon Carbides (but as discrete) in another dac. Its quite surprising the effect you can get playing about with the rectifiers

For the Caiman I'm just going to try running the supply after the input DC diode just to see, for the STR I just use a rectifier made from UF4002

That's what I use in my SupperTeddy supply. Specifically part number SEMI-68495. I chose that over the 22A one because I brefered the case style.


Am I likely to gain any sort of improvement by swapping this to a bridge made out of 1N5822 schottky diodes?
EDIT: I just thought; the 1N5822 is 40V. I'm currently feeding my bridge with about 24V AC and getting about 38V DC out the other end. Are 1N5822 diodes still suitable for this application?

Thanks.