Radar Chip Revolutionizes Smart Dispenser Technology

Driven by radar chip innovation, a WTSound client in Dongguan’s electronics hub is undergoing a quiet technological transformation. This leading supplier of traditional hand-press liquid dispensers once occupied a solid position in the personal care product market due to its shipment volume. Now, as smart touchless dispensers become the new global hygiene standard, the company faces a crucial turning point—how to use technology to break through and capture the mid-to-high-end market?

01 The “Sunlight Dilemma” of Traditional Infrared Solutions

The client’s first smart liquid dispenser product has already entered the market, exported to Chicago and other international destinations. This product uses a classic structure consisting of an MCU, power circuit, motor driver, and infrared sensor, powered by six dry batteries for up to two years of use. However, the technical team soon discovered serious flaws in traditional infrared sensors in real-world applications.
★ Under direct sunlight, this problem becomes nearly unsolvable in outdoor or window-side environments, with sensing distance sharply reduced.
★ Even more troublesome, the sensing distance varies significantly when detecting dark or black materials or different skin tones—this may trigger discrimination risks in high-end commercial venues and hinder market entry in Europe and the U.S.
★ In brightly lit environments, passersby can easily trigger false activations. The material and color (white or black plastic) of the dispenser shield also affect performance. Due to physical limitations, these issues cannot be fully eliminated.

For a smart product targeting international mid-to-high-end users, such technical bottlenecks not only affect user experience but may also shake brand competitiveness in global markets.

02 Dual-Track Approach: Two Technical Solutions for Different Needs

Facing the limits of infrared technology, WTSound took a pragmatic path instead of full replacement—offering two parallel technical solutions tailored to different application scenarios and market demands.

Solution 1: WT40 Series Infrared Module—Upgrading Traditional Product Lines

Not all infrared sensors are the same. The WT40 series infrared sensors have tenfold better resistance to sunlight interference compared to ordinary ones. Through algorithm optimization, they effectively avoid false triggering caused by direct sunlight. The module is compact, supports object detection up to 100 cm, and has ultra-low standby power consumption of 1 μA with only 10 μA working current. Its operating voltage range (2.5 V–5.5 V) maximizes adaptability to different power supply designs.

More importantly, the WT40 series is an ultra-low-power, high-performance optical proximity sensor with an integrated transmitter, proximity detection photodiode, high-resolution ADC, programmable constant-current LED driver, and DSP digital processing unit. The external MCU reads ADC data through an I²C interface and supports interrupt functions without polling, improving system efficiency. This greatly reduces development time and makes it a highly cost-effective upgrade solution for standardized markets that need quick iteration and cost control.

Solution 2: WT41 Series Radar Chip Module—For a New Product Line

For products aiming at top performance and high-end markets, WTSound recommended the WT41 series radar module. This technology uses microwave-band electromagnetic waves—by transmitting microwaves and receiving their echoes, it analyzes time delay, frequency shift, and phase difference to detect targets, fundamentally avoiding the physical limitations of infrared systems.

Advantages of Radar Chip Sensors

1. Unaffected by sunlight, maintaining stable sensing distance
2. Insensitive to color or material differences, highly adaptable
3. Power consumption about 10 μA, fully meeting two-year battery life requirements
4. Radar modules can sense through glass or plastic casings, enabling greater flexibility in product structure design

The client’s chosen WT41 radar module measures only 18 mm × 12 mm × 1.6 mm, with a sensing range of 0.5–2 m and a 3.3 V power supply (not below 3.0 V). It can be directly mounted or embedded into existing circuit boards, requiring only that the antenna surface be fully exposed or behind a penetrable material to ensure signal transmission.

03 From Lab to Production Line: Precision Matching of Dual Solutions

Each solution requires distinct tuning strategies.

For the WT40 infrared solution, the client continues using the existing product structure, fine-tuning response speed levels and sensing thresholds for rapid upgrades. The key advantages: low modification cost and short validation cycles—ideal for fast market penetration in price-sensitive mid-range segments.

The WT4101 radar solution, however, demands more precise integration. Through PC-based software, the engineering team can accurately configure sensing thresholds (e.g., 5% energy levels), adjust transmission power and response speed, and balance sensitivity with power consumption. Tests showed that white reflective surfaces caused false triggers, so the team optimized shielding design to bring the false trigger rate within control.

Although the radar module’s peripheral circuitry is simple, the antenna area must remain exposed or behind a penetrable surface to ensure proper signal operation. Side scattering may cause false activations, and the module’s size is slightly larger than existing infrared ones, requiring PCB redesign—technical refinement necessary for high-end products.

Behind the dual-solution strategy lies deep market insight.

From medical devices to commercial coffee machines, charging stations to luxury hotels, smart devices involving liquids demand highly stable sensing performance. Medical devices require constant liquid temperature to prevent cold stimulation; commercial equipment demands near-perfect reliability. Such high-value markets have rigid requirements for radar’s penetration and stability.

Meanwhile, for schools, communities, and regular commercial venues, the upgraded WT40 infrared solution fully meets daily use. With 1 μA standby power, 100 cm detection range, minimal external components, and high sensitivity, it achieves an optimal balance between performance and cost.

WT40 safeguards the base market volume, while WT4101 pioneers mid-to-high-end markets and complex scenarios. Dual tracks secure existing share and open space for future growth.

04 Market Demand Behind Technology: Higher Stability and Broader Applications

Every technological upgrade serves a larger purpose than fixing a single product. In the personal care and hygiene manufacturing sector, as consumers demand higher hygiene and convenience, traditional manual dispensers are rapidly transitioning to smart touchless models. Competition in this field is fierce—products must balance functionality, performance, stability, and cost.

From medical equipment to commercial coffee machines, charging stations to luxury hotels, the demand for stable sensing performance in liquid-handling smart devices keeps rising. The radar solution’s successful implementation opens broader possibilities for clients. Medical equipment requires constant liquid temperature to avoid cold irritation, while commercial devices demand exceptional reliability—these high-value markets are their next growth targets.

From the technological upgrade of a single smart dispenser to an industry-wide sensor revolution, WTSound continues to help clients achieve breakthroughs that redefine the “smart touchless” standard. As global hygiene awareness grows, this leap from infrared to radar represents not just a product iteration but a strategic transformation for manufacturers entering international markets.

When sunlight no longer poses interference, and skin tone no longer affects performance, the smart liquid dispenser truly reaches every place where it is needed.