I got this from a dosing pump control circuit.
we use cool IC is no. lm317 circuit, It can uses with power supply source 24VDC and adjust voltage output 1.25V to 24V for DC motor 24V.
It is really simple motor control circuit. because there are a few parts and easily to build.
Read More Source : http://www.geocities.com/dsaproject/electronics/cook-book/cook-book.html#5
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