• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

Ideal bridge rectifier GB

Jump to Latest
D

DPH

Member
Joined 2008
analog_sa said:
Have you considered using GaN transistors?
Click to expand...

The "switching" frequency of this synchronous rectification circuit and the modest voltage requirements herein basically wastes any advantage SiC/GaN transistors provide. This is definitely a place to look for slower plain-Jane Si very-low R_dson/modest C_gs switching transistors sized appropriately for the load requirements.

When you want a high efficiency >1 MHz switching power supply network, then the exotics make a lot more sense.
 
iTiberius

iTiberius

Member
Joined 2005
xrk971 said:
...
One thing I am unsure of, is how the transients of the resulting sawtooth wave looks after the bulk cap? Does it even look like a diode sawtooth? Or will it be a total mess? ...
Click to expand...

At full load on my Zeno regulator. Measured directly on the cap after Saligny.

Regards,
Tibi
 

Attachments

  • WhatsApp Image 2019-02-12 at 21.19.00.jpeg
    WhatsApp Image 2019-02-12 at 21.19.00.jpeg
    176.9 KB · Views: 1,501
xrk971

xrk971

Founder of XSA-Labs
Joined 2012
etsy.com/shop/XRKAudio
Paid Member
Hi Do,
You might want to look at the ESR of the CRC caps. In this application, low ESR is not always good as it has very high ripple current and high turn on transient. For Class A power supply the current is steady so need for ultra low ESR is not justified like Class AB amps. Check ripple current rating of those caps and good rule of thumb is that ripple current is about twice steady state current.

These active bridges are very attractive for Class A where running a 5A bias current will result in many watts of dissipation vs <1w with the active bridge.
 
iTiberius

iTiberius

Member
Joined 2005
pinnocchio said:
Hi Tibi,

I'd like to use this on a CCRC PSU for a Class A amplifier, which will be using 3x 68000uF, 8 mOhms ESR caps per rail and the R will be 0.1 Ohm. I was planning to use two bridges for the PSU (one per rail). Do you think the inrush would be too high for these bridges?

Thanks
Do
Click to expand...

Saligny will handle very high peak currents, far above your transformer capability. What you need to take in consideration is your trafo secondary that, for sure, will need to deliver serious current to keep these caps charged and as xrk971 mentioned, low ESR is not the right choice in class A operation.

Regards,
Tibi
 
You must log in or register to reply here.
Top Bottom