LM5109B: What is the main difference between LM5109A and LM5109B?

Bjornar Syverstad

Prodigy 30 points

Part Number: LM5109B
Other Parts Discussed in Thread: LM5109A

Hello,

Today we are using LM5109A, but we might change to LM5109B.

What is the main different between these parts? They seems very similar for me.

Only different I see is that LM5109B datasheets contains more data.

over 7 years ago

0 John Stevens over 7 years ago

TI__Expert 7395 points

Bjornar,

Thanks for your question. I'll have an applications engineer comment soon.

Regards
John

0 Daniel Ruiz over 7 years ago

TI__Intellectual 2910 points

Bjornar,

LM5109B has an increased UVLO functionality that holds the high side FET off when the main VDD supply voltage falls before the HB (bootstrap) voltage decays. The relevant tables are found in the LM5109B's datasheet, in the Start-Up and UVLO section.

Basically, if VDD UVLO is not satisfied, neither high-side nor low-side FETs can be turned on.

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- Daniel

Power management

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LM5109B: What is the main difference between LM5109A and LM5109B?