# Line tracking module, QTR-8RC, with 8 IR channels, Analog, 3-5V

- Page: https://sigmanortec.ro/en/line-tracking-module-8-channels-analog
- Price: 15.19 RON
- Availability: In stock; 1-2 zile
- Reference: 33351 · EAN: 5940212489796
- Category: Mechatronics and IoT > Sensors and Modules > Light and Optical Sensors
- Specifications: Input Voltage: 3 - 5 V; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.
- Package (shipping data): 0.005 kg
- Updated: 2026-09-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 04:49 (Europe/Bucharest)

## Description

The 8-channel analog line tracking module, ideal for line robots, accurately detects the path through infrared sensors. It operates at 5V, provides analog outputs that are easy to read by the microcontroller, allows for fine contrast calibration and interpretation, and the QTR8 configuration covers different bandwidths for stable and fast tracking.
The QTR-8RC module is an array of 8 infrared reflectance sensors, designed especially for line-following robots, but also perfectly usable as a general proximity or reflectance sensor. On a compact 75 x 12.7 mm board, 8 IR emitter-receiver pairs (IR LED and phototransistor) are mounted, evenly spaced at 9.525 mm (0.375"). Each channel is completely independent, providing a separate analog output that can be measured by any analog input line on a microcontroller.
The module is compatible with Arduino Uno, Arduino Nano, STM32, ESP32, ESP8266, Raspberry Pi Pico, and any other platform with analog inputs, operating at both 3.3V and 5V. Switching from 5V to 3.3V is done through a dedicated bypass pad on the board, with no additional external components required.
Among the module’s key features are: independent analog outputs for each channel that allow direct reading via analogRead, a series-paired LED arrangement that cuts current consumption in half, a MOSFET with a default HIGH gate for LED control (the LEDON pin can be left unconnected for continuous operation or connected to a digital line for active control), total board current under 100mA at an LED current of 20–25mA per channel, and an optimal detection distance of 3mm from the surface — the correct distance is critical, as being too close to the surface prevents IR light from reflecting back to the sensor, resulting in incorrect readings.
Specifications:
Dimensions: 74.93 x 12.7 x 3.18 mm (without header pins)
Supply voltage: 3.3 - 5.0V
3.3V bypass pad: yes, available on the board
Total board current: approx. 100 mA
LED current per channel: 20 - 25 mA
Output format: analog
Number of channels: 8
Sensor spacing: 9.525 mm (0.375")
Optimal detection distance: 3 mm (0.125")
Recommended maximum distance: 9.5 mm (0.375")
Weight (without header pins): 3.09 g (0.11 oz)
Compatibility: Arduino Uno, Arduino Nano, STM32, ESP32, ESP8266, Raspberry Pi Pico, any MCU with analog input
Pinout:
Pin
Label
Description
1
VCC
3.3V or 5V power supply
2
GND
Common ground
3
LEDON
LED control: HIGH = on, LOW = off, default on
4
OUT1
Analog output for sensor 1, leftmost
5
OUT2
Analog output for sensor 2
6
OUT3
Analog output for sensor 3
7
OUT4
Analog output for sensor 4
8
OUT5
Analog output for sensor 5
9
OUT6
Analog output for sensor 6
10
OUT7
Analog output for sensor 7
11
OUT8
Analog output for sensor 8, rightmost
Usage:
Connect VCC to the microcontroller’s 3.3V or 5V pin. For 3.3V operation, enable the bypass pad on the board.
Connect GND to the circuit’s common ground.
The LEDON pin can be left unconnected (the LEDs are on by default) or connected to 5V for safety. Connecting it to a digital line allows active LED control.
Connect OUT1-OUT8 to analog pins A0-A7. On Arduino Nano, all 8 sensors are available directly. On Arduino Uno, only 6 analog pins (A0-A5) are available, which is sufficient for most line-following applications.
Mount the module parallel to the detection surface at a distance of about 3mm. The correct distance is critical — if it is too close to the surface, some sensors will report maximum values regardless of surface color.
Read the analog values with analogRead and set a threshold between the values obtained on the white surface and on the black line.
A low value indicates a white surface with high reflectance. A high value indicates a black surface with low reflectance.