In 2001, the EU required that no-load power loss for rated output power 0.3W~70W was 1W; in 2005, the EU changed this standard to no-load power loss for rated output power 0.3W~50W. The no-load power loss of 0.3W and rated output power 15W~70W is 0.75W. It can be seen from this that everyone's requirements for the power consumption of electrical products are becoming increasingly strict. In order to comply with various specifications for product power consumption set by organizations such as the European Union, many new technologies have emerged. The main idea is to allow switching power supplies to operate at a lower switching frequency when the load is small or in standby mode with no load.
The UCC28600 power supply solution provided by TI adopts a power control method that combines quasi-resonant zero voltage and fixed-frequency discontinuous modes in the 30% to 100% output power range, as well as a drive capability of up to 1A. The switching loss of the flyback power supply is greatly reduced, and the operating efficiency of the whole machine reaches more than 85%; in the 10% to 30% output power range, the power supply control method of the fixed peak current off-time modulation mode is used to make the power supply dynamic The load response and conversion efficiency in the low power section have been greatly improved; at the same time, a pulse-skipping standby control mode is adopted in about 10% of the output power section, making the standby power consumption as low as 150 milliwatts.
UCC28600 can directly drive flyback power supplies up to 200 watts. At the same time, UCC28600's own pin function can automatically shut down the PFC function in standby mode, making the user's design simpler and cheaper. .