LNK306
Posted by: vsancak
on
Dear Sir,
I read a document "3-Phase AC/BLDC High Voltage Power Stage Board" from Freescale semiconductor company.
They used LNK306 (please see the picture) after the bridge rectifier and the input of LNK306 is DC voltage (320 V DC).
Is this configuration possible? We were looking a way to produce 18 V DC from 320-560 V DC servo driver bus voltage for the gate driver ICs.
Best Regards,
Vedat
댓글
Dear Sir,
You mean the capacitor in the red circle, don you?
We will add ir if your design does not workproperly
best regards,
Hi, i am working in a desing using that IC, and that capacitor must be there, at least i think that for what i read in the AN-37:
"If the total system capacitance is >100 µF or the output voltage
is >12 V, then during startup the output may fail to reach
regulation within 50 ms, triggering auto-restart operation. This
may also be true when the load is not resistive, for example, the
output is supplying a motor or fan. This is not applicable for the
LNK302 as it does not have the auto-restart function.
To increase the startup time, a soft-start capacitor can be added
across the feedback resistor"
I hope u find this usefull, i also want to suggest you to read the AN37 which is a design guide for this LinkSwitch family.
Yes such a configuration is possible.
Have a look at the product family page:
http://www.powerint.com/en/products/linkswitch-family/linkswitch-tn
and appnotes, where such a "buck converter" (the name of the topology) is described:
http://www.powerint.com/sites/default/files/product-docs/an37.pdf
I also presume that Freescale tests their published circuits as well as Power Integrations does! They added C409 - I'm not sure why - it might be a kludge for a layout related problem.