[Moved]: DC-DC controller recomendation/finder

[skenn_ie]

Hi All. I have been looking for a controller for an isolated DC-DC converter with at least 3 interleaved phases. Ideally, the controller should have an SPI or IIC interface to adjust the dutycycle/Vout and read back Vout to an Arduino., but I could fool the regulator by using an SPI or IIC pot in the feedback circuit. I want to use a 16 - 20V power source, and similar on the isolated output. That would work well if Vout on the primary was maybe 10V. A high transformer ration isn't good in my experience.

Can anyone recommend a controller for this ?

Thanks

 

[treez]

say you set D high for max load, then suddenly someone suddenly disconnects the load.....how do you ensure your output voltage doesn't sky high......I suppose you need output overvoltage trip, but better still , you need a negative feedback loop to control the D...if you do that in software then that is very difficult...a co called converter technology in reading are tryin gto make a range of controllers that close the loop in software, and all us the user does is literally key in what we want vout to be, fsw, feedback loop bandwidth etc.

 

[skenn_ie]

The load, a battery, will be permanently connected. The output will be isolated.
I may have to program a PIC, but had hoped to find a single chip to do the 3-phase interleaved PWM, the only ones I have found are for high current, sub 3V work.

 

[BradtheRad]

Here's a possibility for experimentation...

4017 counter IC rotates pulses to 3 Nand gates. This yields control signals which are staggered 120 deg. Duty cycles overlap.

You can adjust duty cycle within certain limits, by the diode-resistor-capacitor network.



By substituting 'And' gates, you get a different pattern of 'On' times, and a different range of duty cycles.

You are not limited to just 3 outputs with a 4017 IC.

 

[treez]

http://cds.linear.com/docs/en/datasheet/6902f.pdf

LTC6902 PROvides 2,3 or 4 interleaved oscillator outputs that can be used to sync mulitpl smps in interleaved phase

 

[Velkarn]

look at UCD-series (UCD3138, etc) from TI