Controller in Minty Box for Water Valve

This water valve controller is based on an Arduino which has the capability of accepting remote RF commands while controlling the valve solenoid.

A very popular casing among hobbyists is the minty box which encloses all the necessary components including an additional DC/DC step-up converter LT1303 that provides the needed +/- 24V of water valve. The converter raises the voltage from Li-Poly 3.6V to acceptable voltage for opening solenoid. Some MOSFETs are used to switch between +24V or -24V to the solenoid because of their power efficiency. An Arduino pro mini was used to program the valve since it was suitable and tiny.

The 3.6V battery directly powers the circuit as the shutdown of LT1303 is controlled using the Arduino pin 6. When the valve needs to open or close, the voltage booster is turned ON. Both pins 8 and 9 of Arduino are set to low start which is used to control the opening or closing of the solenoid. The circuit may get shorted and cause damage if both pins were set to high at the same time.

For manual control of the valve, a front power switch was added.

Rest of the project