Can the LP8545 load share on the 6 current sinks

Christopher Allen

Other Parts Discussed in Thread: LP8545, LP8556

I have used the LP8545 on a design and like it. Have a new design where I have two LED strings. The load on each is about 110mA with a voltage of 8.1V to 9.3V. I think i can get there if I load share three current sinks on each string. I don't need I2C but do need a PWM input. Is there another IC that would work better?

over 10 years ago

0 Tomi Koskela over 10 years ago

TI__Genius 11020 points

Hi Christopher,

Yes it is possible to connect LED outputs together to drive two strings. Connect OUT1, OUT3, OUT5 together to drive first string and OUT2, OUT4, OUT6 to drive the second string. This is to get the phase shifting working properly for the two strings.

Only issue with the configuration you have is the minimum boost output voltage of 10V. So it is possible that you will have some excessive headroom voltage on LED drivers.

0 Christopher Allen over 10 years ago in reply to Tomi Koskela

Prodigy 40 points

Thanks Tomi,

I understand the issue with the voltage overhead and would prefer not to have it. Does TI have a part that would work better in my new application? I have looked but have not seen one yet.

Chris

0 Tomi Koskela over 10 years ago in reply to Christopher Allen

TI__Genius 11020 points

How about LP8556?

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Can the LP8545 load share on the 6 current sinks