Pololu QTR-8RC Reflectance Sensor Array

Artikelnummer: PO961

This sensor module has 8 IR LED/phototransistor pairs mounted on a 0.375" pitch, making it a great detector for a line-following robot. Pairs of LEDs are arranged in series to halve current consumption, and a MOSFET allows the LEDs to be turned off for additional sensing or power-savings options. Each sensor provides a separate digital I/O-measurable output.

Kategorie: Pololu QTR Reflectance Sensors


9,39 €

inkl. 19% USt.,

momentan nicht verfügbar


Beschreibung

Overview

Note: The QTR-8RC reflectance sensor array requires digital I/O lines to take readings. The similar QTR-8A reflectance sensor array is available with analog outputs, and the reflectance sensor is available individually as a QTR-1RC reflectance sensor or QTR-1A reflectance sensor.

Functional Description

The QTR-8RC reflectance sensor array is intended as a line sensor, but it can be used as a general-purpose proximity or reflectance sensor. The module is a convenient carrier for eight IR emitter and receiver (phototransistor) pairs evenly spaced at intervals of 0.375"" (9.525 mm). To use a sensor, you must first charge the output node by applying a voltage to its OUT pin. You can then read the reflectance by withdrawing the externally supplied voltage and timing how long it takes the output voltage to decay due to the integrated phototransistor. Shorter decay time is an indication of greater reflection. This measurement approach has several advantages, especially when coupled with the ability of the QTR-8RC module to turn off LED power:

  • No analog-to-digital converter (ADC) is required
  • Improved sensitivity over voltage-divider analog output
  • Parallel reading of multiple sensors is possible with most microcontrollers
  • Parallel reading allows optimized use of LED power enable option

The outputs are all independent, but the LEDs are arranged in pairs to halve current consumption. The LEDs are controlled by a MOSFET with a gate normally pulled high, allowing the LEDs to be turned off by setting the MOSFET gate to a low voltage. Turning the LEDs off might be advantageous for limiting power consumption when the sensors are not in use or for varying the effective brightness of the LEDs through PWM control.

This sensor was designed to be used with the board parallel to the surface being sensed.

The LED current-limiting resistors for 5 V operation are arranged in two stages; this allows a simple bypass of one stage to enable operation at 3.3 V. The LED current is approximately 20?25 mA, making the total board consumption just under 100 mA. The schematic diagram of the module is shown below:

For a similar array with three sensors, consider our QTR-3RC reflectance sensor array. The sensors on the QTR-8RC are also available individually as the QTR-1RC reflectance sensor, and the QTR-L-1RC is an alternative designed to be used with the board perpendicular to the surface.

Specifications

  • Dimensions: 2.95"" x 0.5"" x 0.125"" (without header pins installed)
  • Operating voltage: 3.3-5.0 V
  • Supply current: 100 mA
  • Output format: 8 digital I/O-compatible signals that can be read as a timed high pulse
  • Optimal sensing distance: 0.125"" (3 mm)
  • Maximum recommended sensing distance: 0.375"" (9.5 mm)
  • Weight without header pins: 0.11 oz (3.09 g)

Dokumente

Bedienungsanleitung

Bewertungen (0)

Durchschnittliche Artikelbewertung

Geben Sie die erste Bewertung für diesen Artikel ab und helfen Sie Anderen bei der Kaufenscheidung:

----

ähnliche Produkte:
Pololu QTR-1A Reflectance Sensor (2-Pack) Pololu QTR-1A Reflectance Sensor (2-Pack)
momentan nicht verfügbar
Pololu QTR-1RC Reflectance Sensor (2-Pack) Pololu QTR-1RC Reflectance Sensor (2-Pack)
1 Packung auf Lager
Pololu QTR-3A Reflectance Sensor Array Pololu QTR-3A Reflectance Sensor Array
8 Packung auf Lager
Pololu QTR-3RC Reflectance Sensor Array Pololu QTR-3RC Reflectance Sensor Array
29 Packung auf Lager
Pololu QTR-8A Reflectance Sensor Array Pololu QTR-8A Reflectance Sensor Array
momentan nicht verfügbar
Pololu QTR-L-1A Reflectance Sensor (2-Pack) Pololu QTR-L-1A Reflectance Sensor (2-Pack)
1 Packung auf Lager
Pololu QTR-L-1RC Reflectance Sensor (2-Pack) Pololu QTR-L-1RC Reflectance Sensor (2-Pack)
5 Packung auf Lager
Kunden kauften dazu folgende Produkte
Pololu TB6612FNG Dual Motortreiber Carrier Pololu TB6612FNG Dual Motortreiber Carrier
momentan nicht verfügbar
HC-SR04 Abstandsmessung Ultraschall Ultrasonic Sensor Module HC-SR04 Abstandsmessung Ultraschall Ultrasonic Sensor Module
122 bestellt, am 01.12.2019 erwartet
V-TEC 6V Micro 10x12mm DC Motor Getriebe Motor... V-TEC 6V Micro 10x12mm DC Motor Getriebe Motor...
2 Packung auf Lager
Makeblock Injection omnidirectional wheel(Pair) Makeblock Injection omnidirectional wheel(Pair)
50 bestellt, am 23.11.2019 erwartet
XL6009 DC-DC einstellbarer Step-UP Spannungsregler Power... XL6009 DC-DC einstellbarer Step-UP Spannungsregler Power...
3 Packung auf Lager