Switched Mode Power Supplies (SMPS)

[alkasar]

Originally Posted by Cristi

Al, please use a 2 components epoxy which can settle in less than one hour to secure the core of the transformer.

Thanks Cristi
SMPS works perfectly well. Not noisy except when in the sub. The sub vibrations makes the transformer frame vibrate.

I am not sure where exactly to put the glue...

a lot, as shown with the two blue lines to fill the gap ?
or a little glue, in the corners only for better heat dissipation ?

ps: I sent you another email address to reach me.

[Esperado]

Originally Posted by Cristi

I always get that error with message not delivered from "Mail Delivery Subsystem"

Tring to get a new password on your web site, to write a (positive) review for one of your SMPS, i asked for a new password. 5 times. While you web site says " Success: A new password has been sent to your e-mail address.", i never received any.
And, yes, my POP3 mail server works perfectly.

[maxlorenz]

Dear Cristi,

I just bought a pair of your 500W SMPS (QR and R) but was not patient enough to wait for answers to several questions I had...now that I found this thread, I will abuse of your kindness:

1) What is the difference between R and QR?
2) What is the expected ripple output with, say +/-36VDC?
In other words, would I benefit from a power regulator after them?
3) Which of your SMSP have extra aux. low voltage outputs?

Thank you very much.
M.

[maxlorenz]

Originally Posted by Esperado

Projet : Ampli à base de LME49830 - "Gran Torino 150" - Page 49 - Amplification.
He had done it with a simple mesh metallic plate.
It was an amusing thread to read for me, because he was searching a power supply noise problem, when it was evident from the beginning this was an RFI problem on the input line of his amplifier, coming from the SMPS.
Note that he got, with twisted power wires between SMPS and Amplifier: 32mV of noise, not so bad ? JWithout twisted wires, it was 37.5mV .

OK. I found a very good answer to question nº2 from dear Esperado, post #295.
Merci bien, mon cher.

[glt]

"R" is resonant design as in "soft switching". QR is "quasi-resonant" design as in "not so soft switching". Mainly "soft switching reduces RF noise. See this for additional info: Connex SMPS300RE | H i F i D U I N O

[maxlorenz]

Thank you!

[Cristi]

Esperado, please try to create a new account. I tried and cannot find a way to reset the pasword. the website sw is old and lacks of many functions.
Maxlorenz, I will try to answer to your questions in the same order:
1. SMPSxxxR - Resonant, LLC topology, fully regulated and adjustable output voltage. SMPSxxxQR - Quasi Resonant topology unregulated output voltage, proportional with mains input voltage and 5-10% variable from low load to full load. Main advantage, the SMPS200QR, SMPS240QR, SMPS300QR, SMPS3K6QR and SMPS4k8QR have the highest efficiency, about 1.5-2% higher than similar power resonant, regulated SMPS with same output power and at least 7-10% higher efficiency and 12-18dB lower switching noise compared with other similar SMPS on the market offered by competitors. Since it's output voltage is unregulated is suitable for amplifiers with higher PSRR.
2. For R series, is within tens of milivolts range, up to 100mV for highest output voltage versions. For QR series, there is a high-frequecy ripple component with similar amplitude as for R series, tens of mV, overimposed on mains freq. ripple, 100 or 120Hz due to the fact that the output voltage is not regulated and follow mains voltage variations. Before throwing stones at me, make sure you fully understand these terms, and you compared with these information with competitors offerings, 80-90% of them are offering unregulated SMPS only, often with much lower efficiency and worse EMI values.
3. All SMPS have at least one aux. voltage output, some of them are aditionally regulated using LM78xx regulators.

[maxlorenz]

Thank you very much dear Cristi.

Everything understood. Good options. I'll let you know my impressions.

Regards,
M.