rolexbene
Member
I looked at them originally, but i thought i could get a 5a one and save on running cables, that will teach me to be lazy.[/quote]
No the trick is to get one driver that supplies 60v at 900ma and wire the led's in series.
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Cheap Lighting ideas?
- Thread starter Brian Murphy
- Start date
I looked at them originally, but i thought i could get a 5a one and save on running cables, that will teach me to be lazy.[/quote]
No the trick is to get one driver that supplies 60v at 900ma and wire the led's in series.
Actually these LED's with multiple chips per package are a bit of a nightmare as well especially if not from Cree, Osram etc.
The ones you pointed out consist of three parallel strings of 3 white LED's and suffer from current hogging when LED's are in parallel. Below is picture showing what can happen. One column is hogging the current (and being over driven) at the expense of other two columns. Overall light output is same'ish but lifetime is seriously reduced due to overdriving one column.
The big boys, Cree, Osram get round this if they have more than one LED in a package, because they make the LED's, they use LED's from same wafer thus have same electrical characteristics and employ clever LED material so to current limit. Generally though for multiple LED packages they place all the LED's in a series, thus need say 70V drive or pin out each LED string individually.
The ones you pointed out consist of three parallel strings of 3 white LED's and suffer from current hogging when LED's are in parallel. Below is picture showing what can happen. One column is hogging the current (and being over driven) at the expense of other two columns. Overall light output is same'ish but lifetime is seriously reduced due to overdriving one column.
The big boys, Cree, Osram get round this if they have more than one LED in a package, because they make the LED's, they use LED's from same wafer thus have same electrical characteristics and employ clever LED material so to current limit. Generally though for multiple LED packages they place all the LED's in a series, thus need say 70V drive or pin out each LED string individually.
