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Electronics => Electronics => Topic started by: Tomomastchi-project on January 06, 2009, 09:33:33 AM

Title: Power supply
Post by: Tomomastchi-project on January 06, 2009, 09:33:33 AM: Hello,
I am currently working on a PIC project. I have a problem: I need to feed a 6V motor(through a motor control IC) from a 12V battery. I already tried to search "DC DC converter 12V 6V" on google, but it doesn't give any reasonable schematics which do not use 6V*1.5A=9W apart from the 9W the motors use. I do not want to throw away half the energy.
I think I should use something like a step-down converter. Would this http://www.elecfree.com/electronic/12v-to-5v-3a-dc-converter-step-down-regulator/ (http://www.elecfree.com/electronic/12v-to-5v-3a-dc-converter-step-down-regulator/) suit my needs?

Thanks
Title: Re: Power supply
Post by: Geir on January 06, 2009, 10:37:15 AM: You could use a switching regulator, its more efficient then the liner ones. I used that on a project ones
Title: Re: Power supply
Post by: pomprocker on January 06, 2009, 10:54:40 AM: http://www.dimensionengineering.com/AnyVoltMicro.htm
Title: Re: Power supply
Post by: Rebelgium on January 06, 2009, 11:11:09 AM: Quote from: Tomomastchi-project on January 06, 2009, 09:33:33 AM
Hello,
I am currently working on a PIC project. I have a problem: I need to feed a 6V motor(through a motor control IC) from a 12V battery. I already tried to search "DC DC converter 12V 6V" on google, but it doesn't give any reasonable schematics which do not use 6V*1.5A=9W apart from the 9W the motors use. I do not want to throw away half the energy.
I think I should use something like a step-down converter. Would this http://www.elecfree.com/electronic/12v-to-5v-3a-dc-converter-step-down-regulator/ (http://www.elecfree.com/electronic/12v-to-5v-3a-dc-converter-step-down-regulator/) suit my needs?

Thanks

the link you posted isn't a step down converter, it's a lineair converter and will waste half your energy.
the one from dimensionengineering is good.
Title: Re: Power supply
Post by: want2learn on January 06, 2009, 12:02:27 PM: try looking at the L4971 or L4963.
If memory serves they're 8pin dip and only cost about £3-4 each. They're fairly easy to use and a circuit for them is easily designed from the datasheet :)
Title: Re: Power supply
Post by: Tomomastchi-project on January 11, 2009, 06:57:58 AM: Ok. I'll probably go for the L4971 switch regulator. In the datasheet it only shows an example of 3.3V...I need 6V or 5V. What do I need to change? How much current will I be able to draw when I use the L4971 to make 5V from 12V?
Title: Re: Power supply
Post by: Tomomastchi-project on January 11, 2009, 07:12:02 AM: I'm sorry, I overlooked it. I will have to connect an external divider to pin 8.
I hope I can find the part here somewhere.
Thanks guys, I think I will be fine now.