Similarly the Photo transistor also has two pins (Collector and Emitter) which can be used to read the IR signal that is reflected back. The photo diode has two pins (Anode and Cathode) which can be used to generate an IR signal. It has both a Photodiode and a Phototransistor coupled in its package. IR Photodiode, IR LED, qtr-1rC, TSOP, GP2Y0A21 Note: The TCRT5000 datasheet can be found at the bottom of the page Transistor collector current: 100mA (maximum).The Cathode of photodiode is grounded through a resistor The Anode of photodiode is connected to +5V
The emitter of the phototransistor is grounded through a resistor The collector of the phototransistor is connected to +5V
