Mi 67w fast charge can be backward compatible.
Fast charging appliances designed by mobile phone manufacturers have fast charging agreements. The general fast charge protocol is backward compatible, millet 67w to 33w mobile phone charging is completely possible, but may not reach the maximum charging power of 33w. Each charger, his surface is marked with the output voltage output current, you can calculate the voltage times the current is its power.
Xiaomi mobile phone is a national treasure brand mobile phone. Supports fast charging. Mi 67w Fast charge can be backward compatible