LP8866-Q1: Dimming Mode

Youhei Miyaoka

Part Number: LP8866-Q1

Hi experts,

My customer have question about 7.3.8.2 Dimming Mode. In this subsection, it is explained about Mode resistance and its's I2C address.

The question is what is a difference between 0x2B and 0x2A. For example, if we want to set Hybrid mode, it seems to can set 4.74kOhm or 17.8kOhm. Is there any difference?

And this address send to LED driver from Host IC. Is this understanding correct? Or is the direction reversed.

Regards,

Youhei MIYAOKA

8 months ago

0 Zhiqian Wu 8 months ago

TI__Mastermind 19730 points

Hi, Youhei

Sure, address is the only difference. And host needs to communicate with the device with the right address.

0 Youhei Miyaoka 8 months ago in reply to Zhiqian Wu

TI__Intellectual 1745 points

Hi Zhiqian,

Thanks for your answer. I'm sorry for basic question, but let me check the operation of the I2C.

1. Dimming mode decided by mode pin (33pin).

2. The Host IC queries the LED driver for the mode status.

3. The LED driver sends status based on register information.

Is this operation correct?

Regards,

Youhei MIYAOKA

+1 Zhiqian Wu 8 months ago in reply to Youhei Miyaoka

TI__Mastermind 19730 points

Hi, Youhei

Let me explain in a easy way

Our device register can be accessed by I2C. Address is set by Mode pin. If I2C is no used, there are no difference between 0x2B and 0x2A.

0 Youhei Miyaoka 8 months ago in reply to Zhiqian Wu

TI__Intellectual 1745 points

Hi Zhiqian,

Got it. Let me confirm I2C operation when connection was failed because the customer want to know.

In my understanding, user can't set register like USER_CONFIG1 when I2C connection was failed. Is it correct?

Regards,

Youhei MIYAOKA

+1 Zhiqian Wu 8 months ago in reply to Youhei Miyaoka

TI__Mastermind 19730 points

Hi, Youhei

You can check with the register status.USER_CONFIG1 is the R/W(READ&WRITE) register which means it can be set by customer.

I share another register here, 0x16 is a read only register

Power management

Power management forum

LP8866-Q1: Dimming Mode