Analysis of LED Display Scanning Technology: Characteristics of Low, Medium, and High Scanning

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Scanning technology is one of the core technologies of LED display drive systems. Essentially, it utilizes the time-division multiplexing (TDM) principle, where driver ICs light up pixel units row by row/column by column to achieve image display. The core indicator is the scan ratio (or scanning factor), referring to the number of pixel rows controlled by a single drive channel (e.g., 1/8 scan means 8 rows of pixels share one set of drive circuits). Low, medium, and high scanning are classified based on the scan ratio, with significant differences in drive efficiency, brightness, power consumption, and cost. Their specific characteristics are as follows:

I. Low-Scan Technology
Low-scan typically refers to a scan ratio ≤ 1/8 (common types: 1/4, 1/6, 1/8 scan), and it was the mainstream drive solution for early LED displays and outdoor large screens. Core Characteristics
Low driving cost: Requires fewer driver ICs per unit area, with low hardware investment and simplified circuit design—offering the lowest overall cost among the three solutions.
Excellent brightness performance: High duty cycle of single-pixel illumination and efficient current driving enable high brightness output, meeting visibility requirements in strong outdoor light environments.
Higher power consumption and heat generation: Due to fewer rows loaded per channel, the current density is high, leading to relatively high overall power consumption and noticeable heat generation during long-term operation.
Limited refresh rate: Restricted by driving timing, the image refresh rate is generally lower than that of medium and high-scan solutions, with potential flicker in low-frame-rate scenarios.

II. Medium-Scan Technology
Medium-scan generally refers to a scan ratio of 1/8 ~ 1/16 (common types: 1/10, 1/12, 1/16 scan), serving as a balanced solution that combines performance and cost-effectiveness. Core Characteristics
Balanced performance: Driving cost is slightly higher than low-scan but much lower than high-scan; brightness covers semi-outdoor and indoor strong light scenarios, while power consumption and heat generation are better controlled than low-scan.
Moderate refresh rate: Image refresh rate can reach over 1920Hz, satisfying the fluency requirements for regular video playback and graphic display without obvious flicker. Strong adaptability: High compatibility of drive circuits allows flexible adjustment of brightness and power consumption parameters based on scenarios, combining practicality and cost-effectiveness.
III. High-Scan Technology
High-scan refers to a scan ratio ≥ 1/16 (common types: 1/32, 1/48, 1/64 scan; up to 1/128 scan for small-pitch displays), and it is the core drive solution for indoor high-definition small-pitch LED displays. Core Characteristics
High display precision: A large number of driver ICs enable precise control of pixel illumination timing, achieving high refresh rates (generally ≥ 3840Hz) and high grayscale levels. The image is free of graininess and flicker, meeting high-definition viewing needs at close range. Low power consumption and heat generation: More rows loaded per channel result in low current density, leading to significantly lower overall power consumption and heat generation than low and medium-scan
solutions, with stronger operational stability.
High driving cost: Requires a large number of driver ICs per unit area, coupled with high-performance control cards and heat dissipation systems—resulting in the highest hardware and technical costs among the three solutions.
Indoor brightness adaptation: Due to the low duty cycle of single-pixel illumination, the overall brightness is relatively limited. It is more suitable for indoor low-light or regular lighting environments and not applicable to strong outdoor light scenarios.