LP8865Z-Q1: Review of schematic

Shwetanshu Singh

Part Number: LP8865Z-Q1

Tool/software:

Hi,

For an implementation, I wanted to use 2 of these ICs with 4 LEDs. Since the IC is a Low side switching driver, am I correct to assume that connecting the power to input line of the other IC should not be a problem?
Please confirm if the following configuration can be used.

6 months ago

0 Shwetanshu Singh 6 months ago

Prodigy 180 points

Hi,

Please reply at the earliest.

Thanks

0 Zhiqian Wu 6 months ago in reply to Shwetanshu Singh

TI__Mastermind 26595 points

Hi, Shwetanshu

May I ask why you want to connect like this?

And for another requirement, which input IC you want to co-work? Is it a stable input voltage?

0 Shwetanshu Singh 6 months ago in reply to Zhiqian Wu

Prodigy 180 points

Both ICs used above are the same. All connections in the two ICs are identical. The supply is a stable input voltage and is the same for the two ICs.

LED 2 and 4 are placed on a separate PCB and I have a constraint to take out only 1 wire for each LED, hence, a connection like this is required.

0 Steven Li 6 months ago in reply to Shwetanshu Singh

TI__Mastermind 22830 points

Hi Shwetanshu,

Our expert is currently out of office. He will reply to you later. Thanks for your understanding.

Best Regards,

Steven

0 Shwetanshu Singh 6 months ago in reply to Steven Li

Prodigy 180 points

Hi Steven,

Please facilitate a reply at the earliest.

Shwetanshu Singh said:
Both ICs used above are the same. All connections in the two ICs are identical. The supply is a stable input voltage and is the same for the two ICs.

LED 2 and 4 are placed on a separate PCB and I have a constraint to take out only 1 wire for each LED, hence, a connection like this is required.

Given these, is the connection schematic I shared okay to use?

0 Steven Li 6 months ago in reply to Shwetanshu Singh

TI__Mastermind 22830 points

Hi Shwetanshu,

I have talked with our expert. He will be back to the office tomorrow and will then reply to you.

Best Regards,

Steven

0 Shwetanshu Singh 6 months ago in reply to Steven Li

Prodigy 180 points

Hi

Can I get any updates?

Thanks

0 Zhiqian Wu 6 months ago in reply to Zhiqian Wu

TI__Mastermind 26595 points

Hi, Shwetanshu

Correct me if my understanding is not correct.

The input voltage is the same for both two IC, why you doesn't use one IC to drive two LED? For example LED2/3 in one IC and LED1/4 another IC.

We doesn't recommend to use topology like you draw.

0 Shwetanshu Singh 6 months ago in reply to Zhiqian Wu

Prodigy 180 points

Hi Zhiqian,

There are certain restrictions, that I cannot disclose here, due to which I cannot use like you suggested.

Can you please let me know if anything can be done to connect the LEDs in the configuration I want?

Thanks

0 Zhiqian Wu 6 months ago in reply to Shwetanshu Singh

TI__Mastermind 26595 points

Hi, Shwetanshu

Lets talk about the direction of LED and control logic, I give a sample in below, correct my if I am wrong.

Ant control logic of the two IC? what is the current waveform you want for each LED? We never test the topology as you drew, but we can have detailed discuss if you can share more requirement and control logic.