After understanding the functions of the two interfaces in the previous section, we now further analyze their technical core: the complexity of the 60W bidirectional interface far exceeds that of the 12V 6A unidirectional output, which directly affects the product's design cost and performance stability. Below is a key comparison:
Core Conclusion: The 60W Bidirectional Interface is More Difficult to Implement Than the 12V 6A DC Output
The fundamental difference lies in that the 12V 6A DC output is "unidirectional fixed-spec power supply" with mature technology and simple logic, while the 60W bidirectional interface requires "bidirectional switching + power adaptation," involving complex challenges in topology architecture, bidirectional control, and safety protection—resulting in significantly higher complexity and cost.
Difficulty Comparison Between the Two (Clear Presentation in Table)
| Comparison Dimension | 12V 6A DC Output (Unidirectional) | 60W Bidirectional Interface (IN/OUT) | Core Reason for Difficulty Gap |
|---|---|---|---|
| Topology Architecture | Single path (AC→DC rectification + fixed step-down to 12V) | Bidirectional topology (supports both AC→DC charging and DC→DC discharging) | Unidirectional architecture only needs "step-down + filtering," while bidirectional requires symmetric topology (e.g., bidirectional LLC, bidirectional Buck-Boost) to avoid unidirectional component limitations |
| Power Control Logic | Fixed output (12V/6A, constant voltage/constant current mode with no dynamic parameter adjustment) | Bidirectional adaptation (matches power supply specs during charging, adapts to load requirements during discharging) | Unidirectional only needs "stable output," while bidirectional requires real-time direction detection and dynamic voltage/current adjustment, doubling algorithm complexity |
| Safety Protection Mechanism | Basic protection (overcurrent, overvoltage, short circuit—only for output terminal) | Bidirectional full-link protection (overcurrent/overvoltage/reverse connection/overheating for both charging and discharging terminals) | Bidirectional needs to prevent "power reverse connection during charging," "load short circuit during discharging," and "current surge during switching," requiring more protection circuits with higher precision |
| Efficiency & Thermal Design | Fixed power (72W) with a single, mature thermal solution | Dynamic power (0-60W bidirectional switching), requiring thermal adaptation to different operating conditions | Unidirectional thermal design only needs to match fixed power, while bidirectional must handle switching between "high heat during charging" and "low heat during discharging" to avoid local overheating |
| Component Selection Requirements | Ordinary components (unidirectional diodes, fixed step-down chips, conventional capacitors) | High-performance bidirectional components (MOSFET bridges, bidirectional controllers, high-frequency capacitors) | Bidirectional requires MOSFETs with low on-resistance and fast switching speed, plus protocol chips supporting bidirectional communication (e.g., PD protocol) |
