The 6x6 tact switch, with its compact size and sensitive triggering characteristics, is frequently used in control scenarios for various small appliances. Meanwhile, the Type-C interface, when equipped with the PD protocol, offers efficient charging advantages that can significantly enhance the power replenishment efficiency of small fans. This solution integrates the core strengths of both technologies: Type-C PD enables rapid charging, while the 6x6 tact switch serves as the input device. It triggers a counter via pulse signals to cycle through low, medium, high, and stop fan speeds. This design simultaneously fulfills fast-charging requirements and precisely matches airflow needs across different usage scenarios, significantly enhancing user experience and product utility.
Working Principle
This compact fan operates on a closed-loop control system: “pulse signal → count recognition → speed adjustment command output.” When the user presses the 6×6 tact switch, it generates a brief pulse signal (high-to-low level transition). This pulse serves as a count trigger signal transmitted to the counter module. The counter accumulates the number of pulse signals received. Different count values correspond to preset fan operating modes (Stop, Low Speed, Medium Speed, High Speed). When the count reaches the preset maximum value, pressing the switch again triggers the counter reset, restarting the cyclic switching state. This enables convenient operation where each press cycles through one mode.
Advantages of This Mini Fan PCBA
1. User-Friendly Operation: All fan speed modes can be switched using a single 6x6 tact switch, eliminating complex button combinations and ensuring low learning curve.
2. Streamlined Structure: Core modules consist solely of a tact switch, counter, and driver circuit, featuring minimal components, low cost, and easy integration into compact fan products.
3. High Stability: Anti-jitter circuitry and precise counting logic effectively prevent misoperation caused by signal interference, ensuring stable and reliable mode switching;
4. Wide Adaptability: The charging port supports multi-voltage input, while the speed control port allows adjustment of counter presets and speed parameters. This enables compatibility with fans of varying power ratings and types, broadening application scenarios.
Functional Applications of Type-C and 6x6 Tactile Switches
1. Type-C PD Protocol High-Efficiency Charging Solution
Utilizing a Type-C interface paired with a PD protocol chip to build a charging system, leveraging the high-power transmission characteristics of the PD protocol enables charging power up to 100W. This far exceeds the 5W power limit of traditional Micro-USB interfaces, providing hardware support for efficient power replenishment in small fans. Precise regulation by the PD protocol chip enables efficient charging—15 minutes of charging provides 1 hour of runtime. It supports multiple voltage outputs (5V, 9V, 12V, 15V, 20V) and automatically matches the optimal voltage based on the fan battery's charging status. This balances charging speed with battery safety, preventing overcharging and overheating.
2. Signal Processing Module
The raw pulse signals generated by the 6x6 tact switches may suffer from jitter interference (multiple rapid transitions within a short timeframe). These signals require processing through debouncing circuits (such as RC debouncing circuits or Schmitt triggers) to produce stable, single-pulse outputs. The debounced pulse signals are then transmitted to the counter, ensuring precise counting and preventing erroneous switching caused by signal interference.
