LM5110: maximum negative voltage

Masazumi Ishii

Genius 3945 points

Part Number: LM5110

Hello.

I have a question about the LM5110.

Datasheet P4. 7.3 Recommended Operating Conditions
IN_REF to VEE　4V(max)

The maximum negative voltage of this IC is 4 V.
Is this OK?

Is there an IC that supports the maximum voltage of the negative power supply up to 5 V? .

Thank you.

over 5 years ago

0 Don Dapkus over 5 years ago

TI__Guru**** 189399 points

Hi Ishii-San,

That spec is intended for inductive spikes on the switch node pin.

Are you trying to design a circuit that can drive the gate with a negative voltage?

If you can give us more details, we can help you find the best device for your application.

0 Don Dapkus over 5 years ago in reply to Don Dapkus

TI__Guru**** 189399 points

Hi Ishii-san,

Since I haven't heard back from you, I must assume this issue has been solved.

If not, let me know, and we can work on it together.

0 Masazumi Ishii over 5 years ago in reply to Don Dapkus

Genius 3945 points

Hello.

thank you for your answer.

It is on a separate sheet regarding usage.

Thank you.

LM5110-2.pdf

0 Richard Herring over 5 years ago in reply to Masazumi Ishii

TI__Mastermind 20950 points

Hello Masazumi,

I am an applications engineer who works for Don and I will add some suggestions. For the negative bias for the driver and limitation of the 4V on IN REF to VEE I see the concern.

A solution for a simple level shifter with a PNP will allow you to connect IN REF to VEE and level shift the input signal from a GND reference.

Refer to the app note

http://www.ti.com/lit/an/slua169a/slua169a.pdf

to see the level shift of the driver input signal. There are driver solutions that offer much higher ground reference voltage potential than the LM5110, but I think the level shifter is adequate for your application.

Regards,

Richard Herring

Power management

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LM5110: maximum negative voltage