This circuit allows you to use 8 bits of digital output (available on almost all low-end DAC boards) and produce an output voltage of 0 to 10 VDC.  You can use this to control devices that require a 0 to 10 V control voltage (i.e., low current).  I have used this board in conjunction with a DC pulse width modulator (available from Jameco Electronics) to control high current DC lighting and vary the intensity of the light.  Requires 12VDC for operation.