曾經(jīng)有收到過這樣的要求(spec):
Model I:
1. INPUT:90~264VAC
2. PF: 0.9 or above
3. Efficiency: >80%
4. Standby power: < 0.5W or below
5. output: 25V@0.5A
6. THD: <10%
7. OUTPUT CABLE: 3.5M@ 18AWG with switching.
8. Casing size: general 12W's casing
9. Loading: separated 12W LED lamp
10. Comply safety UL1310 and EMC EN55022 Standard or eqv.

Model II:
1. INPUT:90~264VAC
2. PF: 0.9 or above
3. Efficiency: >85%
4. Standby power: < 0.5W or below
5. output: 25V@1.5A
6. THD: <10%
7. OUTPUT CABLE: 3.5M@ 18AWG with switching.
8. Casing size: general 36W's casing
9. Loading: separated 36W LED lamp
10. Comply safety UL1310 and EMC EN55022 Standard or eqv.

    根據(jù)這些要求,我們非常難以選擇方案,因為還有一個最為關(guān)鍵的成本要求跟普通的適配器價格差不多,即使后來有選用SINGLE STAGE PFC方案來實現(xiàn),但其中的問題也非常之多.有這方面的經(jīng)驗大家可以探討一下!