LM5146-Q1: LM5146-Q1 in e-bike battery pack

Ian Wang

Part Number: LM5146-Q1
Other Parts Discussed in Thread: LM5146,

Hi Sir,

My customer considers using LM5146 for e-bike battery pack application.

Condition is Battery Vmax=76V, Vout=12V/8A.

But they consider overshoot will up to 150V, LM5146 support up to 100V, if you have external circuit can share to reduce overshoot for protect LM5146?

Thanks, Ian.

over 2 years ago

0 Timothy Hegarty over 2 years ago

TI__Mastermind 49367 points

Hi Ian,

This is a similar application to the LM5146-Q1 EVM (12V/8A/400kHz).

One option is to clamp the input voltage below 100V with a TVS. This also depends on the duration of the transient.

Regards,

Tim

0 Ian Wang over 2 years ago in reply to Timothy Hegarty

TI__Mastermind 25065 points

Hi Tim,

Pls advise,

1. What is IHYS?

2. How to set resistor as condition?

>42V disable LM5146

<42V enable LM5146

Thanks Ian.

0 Timothy Hegarty over 2 years ago in reply to Ian Wang

TI__Mastermind 49367 points

Hi Ian,

IHYS is the hysteresis current source that turns on when EN/UVLO goes above its rising threshold. It is 10uA (see spec in the EC table of the datasheet).

Note that the input UVLO feature is to enable the controller above a certain input voltage. You need OVLO, which effectively disables the controller above a given input voltage. The easiest way to do this is with an external supervisor that monitors Vin and toggles EN/UVLO as needed.

Regards,

Tim

0 Ian Wang over 2 years ago in reply to Timothy Hegarty

TI__Mastermind 25065 points

Hi Tim,

Excuse let me clarify Q2,

How to set resistor as condition? If we would like deign Vin >42V disable LM5146; Vin <42V enable LM5146.

Thanks, Ian.

0 Timothy Hegarty over 2 years ago in reply to Ian Wang

TI__Mastermind 49367 points

That's not possible with the UVLO function of the LM5146-Q1. You need an external circuit to implement overvoltage shutdown, e.g. a voltage monitor / supervisory IC that pulls EN/UVLO low when Vin > 42V.

Regards,

Tim

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LM5146-Q1: LM5146-Q1 in e-bike battery pack