20-01-2015, 11:17 AM
Wow - that's staggeringly cheap! And it appears to include PFC - how do they do it for that price? Not as EMI-friendly as a 50Hz transformer, and I'd bet that it won't last as long as a 50Hz transformer, but it's hard to argue with the price...
All my halogen desk lights are old enough to have 50Hz transformers mounted in their bases. It does help with stability - indeed, I've seen newer ones that have a weight in their base because the SMPS is so light
I've said it before, but I still find it staggering that at these sorts of power levels, it's cheaper to design, test, seek approvals, and then manufacturer a complex switched-mode PSU than it is to buy some copper and iron. The BOM costs for most of these supplies is about a dollar in the quantities they're produced in. With the rising price of commodities, you can see how things have gone this way - even if it goes against our instincts...
All my halogen desk lights are old enough to have 50Hz transformers mounted in their bases. It does help with stability - indeed, I've seen newer ones that have a weight in their base because the SMPS is so light
I've said it before, but I still find it staggering that at these sorts of power levels, it's cheaper to design, test, seek approvals, and then manufacturer a complex switched-mode PSU than it is to buy some copper and iron. The BOM costs for most of these supplies is about a dollar in the quantities they're produced in. With the rising price of commodities, you can see how things have gone this way - even if it goes against our instincts...
