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I would like to build a DC-DC converter circuit using EasyEDA that can output about 80V from 7 Nissan Leaf battery modules that are about 55V nominal.

I am looking at the datasheet for the LM5164 and page 16 shows an example 12V converter with a parts list on page 17.

I don't know much about inductors; I think I get their basic principle of magnetics but I have never tried to build a functional circuit using inductors before; until now I have just used linear regulators.

The parts list says to use inductor MSS1246T-683MLB but JLC-PCB do not appear to stock this. How would I know if SWPA6045S680MT is an acceptable equivalent?

I assume that resistor RFB1 and RFB2 are generating the reference voltage that sets the output to 12V. What formula would adjust these 2 values to make the output 8V?

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  • \$\begingroup\$ what relevance does the resistance of the inductor have? the datasheet recommends Inductor, 68 μH, 170 mΩ, 1.8A but i cannot find one. I am looking at part SWRB1207S-680MT that clams 68uH 140mΩ 2.1A \$\endgroup\$
    – Jay Dee
    Commented Jul 1, 2022 at 22:23
  • \$\begingroup\$ SWRB1207S-680MT should be OK. Exact resistance should not matter. That inductor probably uses slightly thicker wire to handle slightly higher current, giving slightly lower resistance. Good Luck! \$\endgroup\$
    – emrys57
    Commented Jul 2, 2022 at 11:15
  • \$\begingroup\$ thanks, so far i have made this schematic in EasyEDA link once i have finished it i will print the board and come back here with my findings. im struggling to understand the PGOOD pin at mo, would i be correct in saying it is a sink pin that would connect the negative of an LED via a resistor and only sink power lighting the LED if all is good? \$\endgroup\$
    – Jay Dee
    Commented Jul 3, 2022 at 13:24

1 Answer 1

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I built this circuit and got it working, short of having to change the RON resistor as I accidentally had it printed with an 0805 SMD 1 Ω and not a 100 kΩ resistor by mistake.

The SWPA6045S680MT does work fine.

enter image description here

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