MIKROE-1999 Line Follower click Mikroe MIKROE-1999 Line Follower click is best used for line-following robots and cars. The click carries an array of five Fairchild QRE1113 miniature reflective object sensors. Each sensor consists of an infrared transmitter and infrared receiver. The individual sensors have separate digital outputs, each routed through a single mikroBUS™ pin, for communicating with the target MCU. The pins are OUT1, OUT2, OUT3, OUT4, and OUT5 (in place of default mikroBUS pins RST, AN, PWM, TX, and RX, respectively). Mikroe MIKROE-1999 Line Follower click is designed to use a 3.3V or a 5V power supply.