Description: <br> Type: KY-040 Rotary Decoder Encoder. <br> Operating Voltage: 5V. <br> One round number of pulse: 20. <br> Width: 19mm/0.75 Inches. <br> Length: 30mm/ 1.18 Inches. <br> Height: 28mm/1.10 Inches. <br> Material of Knob Cap: Aluminium Alloy. <br> Diameter of Knob Cap: 14mm/ 0.55 Inches. <br> Height of Knob Cap: 17mm/ 0.67Inches. <br> Package:2 PCS. <br><br> Pin description: <br> CLK - equivalent to output A in regular encoder. <br> DT - equivalent to output B in regular encoder. <br> GND - equivalent to output C in regular encoder. <br> SW - reset switch. <br> + (VCC) - positive supply to the unit. <br><br> The KY-040 rotary encoder is a 360 degree rotary input device (i.e. a control knob) that provides an indication of how much the knob has been rotated AND which direction it is rotating in. <br> It is a great device for stepper and servo motor control. You can also use it to control devices like digital potentiometers. It is ideal for navigating menus on a display or taking inputs such as numbers or text characters. The range of input can be easily defined and mapped in software. A push button switch is built into this encoder. <br> If you push on the shaft, the normally open switch "SW" will close. This can be used as an On/Off switch, to change control functions, ranges, selecting a menu item or entering a number. The "D" shaft of the encoder can be fitted with a knob for using it in a product.<br>