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I'm working with a microcontroller which its supply voltage range is 1.8V to 3.6V

I want to connect a solenoid to this mcu (this solenoid will be activated occasionally).

Current–voltage characteristic of the solenoid:

Input voltage: DC6V

Direct current: 0.35~0.476 A

So, my idea is to connect a 3.6V battery to the mcu and use a DC DC Converter to supply the solenoid.

But the problem is that I cannot find any 3.6V to 6V DC DC converter.

Any help would be really appreciated.

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    \$\begingroup\$ There must be about a zillion boost converters that will operate from a single Li-on cell. Where all did you look so as not to find any? I think there's one stuck on the bottom of my shoe. \$\endgroup\$ – Spehro Pefhany Apr 10 '15 at 16:13
  • \$\begingroup\$ I've contacted to Farnell, Digikey, etc with no luck. They don't have a 3.6V to 6V DC DC converter. \$\endgroup\$ – user204415 Apr 10 '15 at 16:18
  • \$\begingroup\$ First, you don't have to contact a distributor, you look for this on their web site. Second, nobody is going to make exactly a 3.6 V to 6 V boost converter because they wouldn't sell enough. Instead they make general boost converters and you set the output voltage with a resistor divider. Read a few datasheets. \$\endgroup\$ – Olin Lathrop Apr 10 '15 at 19:47
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Here is the first one I found- there are likely better ones for you. Look for adjustable boost converters. 6V is not a common fixed output voltage.

Edit: In general for adjustable regulators to make the output voltage what you want you'll pick a pair of resistors (connected as a voltage divider) such that the divided output voltage is equal to the nominal reference voltage of the chip. Sometimes you may have to take the bias current into account too, and that should be spelled out in the datasheet. In the case of the above chip, here is the schematic for a 12V-output circuit:

enter image description here

The reference voltage is specified as 1.242V. They've picked R1 and R2 such that

FB = 12V \$(\frac {R2}{R1+R2})\$= 1.237V, so the nominal voltage at the output will be a bit higher than 12V (ignoring bias current, which at 40nA is pretty small).

Other parts may have to change besides R1/R2 for your 6V output voltage so be sure to read the datasheet carefully and understand all the nuances. Be particularly careful of the inductor selection and compensation with switching regulators. Some manufacturers have automated online SMPS design pages that will suggest actual part numbers.

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  • \$\begingroup\$ Thanks sir. I've never worked with adjustable boost converters. How do you adjust the output voltage to 6V using that chip ? \$\endgroup\$ – user204415 Apr 10 '15 at 16:51

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