Search found 2 matches
- Fri Dec 03, 2021 2:29 am
- Forum: Miscellaneous
- Topic: Omax fried LED driver PCB -Solved!
- Replies: 5
- Views: 4236
Re: Omax fried LED driver PCB -Solved!
Yes, a rectifier, even just a Si diode, Great idea! A full bridge would drop the input voltage by 2 x 0.6v (forward Si voltage), making a commonly available 5v supply now appear as 3.8v at the LM317. This is just 0.8v above the target 3.0v LED voltage. I think the LM317 needs at least 1.25v above it...
- Wed Dec 01, 2021 3:46 pm
- Forum: Miscellaneous
- Topic: Omax fried LED driver PCB -Solved!
- Replies: 5
- Views: 4236
Omax fried LED driver PCB -Solved!
I, like many other proud owners of Omax LED microscopes, fried my LED PCB -and more by plugging in a wrong voltage but plug-compatible wall-wart. omax_repair_fried_pcb_q1_sm.jpg Many OMAX scopes including my nice M837ZL series scope have a proprietary board DXL80D which is easily damaged by over-vol...