QTR-8RC Line Following Reflectance IR Sensor Array

QTR-8RC is a reflectance sensor array but intended as a line sensor. It can be used as a general-purpose proximity IR or reflectance sensor. The device has 8 pairs of IR LED and phototransistors mounted on a 9.525 mm pitch. 

Each phototransistor in the module is followed by a pull-up resistor that forms a voltage divider and produces an analog voltage output between 0 to 5V as the function of the reflectance sensor. All the outputs are independent but LEDs are paired to halve the current consumption. The LEDs are controlled by MOSFET with a gate normally pulled high that allows LEDs to turn off by setting the MOSFET gate at low voltage. 

Features

• No analog to digital conversion requires
• Improved sensitivity over voltage-divider analog output
• Parallel reading of multiple sensors is possible

Specification

• Operating voltage: 3.3 to 5V
• Current supply: 100mA
• Output voltage range: 0V to supplied voltage
• Output format: 8 digital I/O compatible signal
• Sensing distance: 3mm
• Maximum sensing distance: 9.5mm

Application

• Line following robot
• DIY electronics and robotics projects