Comments on: Simple 12 Volt to 9 Volt DC-DC Converter

By: bgk murthy

bgk murthy — Sun, 04 Mar 2012 15:30:06 +0000

Looking to see if the same configuration could be used upto 5 amps load ?ic

By: psu

psu — Sun, 27 Nov 2011 22:18:38 +0000

In reply to dene helwig. no, the value is correct. it should be in nanofarads

By: dene helwig

dene helwig — Wed, 16 Nov 2011 00:41:54 +0000

what is the value of C3 ? nf(nano farads) , shouldn’t it be pf, for pico farads?

By: Laszlo

Laszlo — Mon, 01 Aug 2011 23:56:00 +0000

Darianto,
The schematic is actually showing a very cheap Linear Voltage Regulator.
Instead of “converting” it’s actually decreases the Voltage by dissipating the overhead (3V in our case)
Smart, efficient converters are use some kind of higher frequency switching technique decreasing (or even increasing if needed) the output Voltage level.
Boost Conversion for increasing, Buck conversion for decreasing.
Answering your question, in theory it’s possible but not really recommended for such high power, since you’re going to dissipate( wasting, and need large heatsink ) about 30W at 10 Amps.
I’m going to help you to work on some switching high efficient DC/DC converter just shot me an Email at laszloee@gmail.com.

Best.
Laszlo

By: psu

psu — Wed, 13 Jul 2011 10:12:47 +0000

In reply to Daryanto Goentoro.

no, this circuit can’t be used for 10A power supply. For 10A converter. Simply use this circuit: http://powersupply33.com/13-8v-10a-dc-regulator-circuit.html
change the LM7812 to become LM7809.

By: Daryanto Goentoro

Daryanto Goentoro — Wed, 13 Jul 2011 06:26:47 +0000

is that 12vdc-to 9vdc usefull for 10A power supply ?? i have 12vdc 10A power supply, and i want to change to 9vdc 10A