Pololu QTR-HD-25A Reflectance Sensor Array: 25-Channel, 4mm Pitch, Analog Output
Description
- Pololu QTR-HD-25A Reflectance Sensor Array: 25-Channel, 4mm Pitch, Analog Output
- Detects reflectance changes with 25 sensors
- Operates within 2.9 V to 5 V voltage range
- Features dimmable brightness control
- Optimizes performance at 5 mm sensing distance
- Measures 101.0 × 16.5 × 2.5 mm
The Pololu QTR-HD-25A Reflectance Sensor Array: 25-Channel, 4mm Pitch, Analog Output is an advanced tool designed for precise detection of reflectance changes, such as those required in line detection applications. This sensor array comprises 25 infrared LED and phototransistor pairs, which are adept at identifying variations in surface reflectivity. The device operates efficiently within a voltage range of 2.9 V to 5 V, providing flexibility in various electronic setups.
The sensor array features dimmable brightness control, which functions independently of the supply voltage, allowing for tailored adjustments to suit specific detection needs. Additionally, it offers separate controls for odd and even emitters, enhancing its adaptability in diverse environments. The absence of lenses in this model maintains the traditional QTR sensor design, ensuring reliable performance.
The sensor's optimal performance is achieved at a sensing distance of approximately 5 mm, with the capability to detect high-reflectance objects up to a distance of 50 mm. This makes it suitable for applications requiring close-range detection with high contrast between light and dark readings.
- 1x Pololu QTR-HD-25A Reflectance Sensor Array: 25-Channel, 4mm Pitch, Analog Output

- 101.0 x 16.5 x 2.5 mm
- Operating voltage: 2.9 V to 5 V
- Sensor type: QTR
- Sensor count: 25
- Sensor pitch: 4 mm
- Full-brightness LED current: 30 mA
- Maximum board current: 405 mA
- Output format: analog voltages (0 V to VCC)
- Optimal sensing distance: 5 mm
- Maximum recommended sensing distance: 50 mm
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