Recommend LED driver solution

Hi,

From your circuit, you need three channels with independent current setting using external resistors?

Hi Kenneth,
Yes , that's correct.
Also need three channels with independent PWM or enable(either one) control.
Please recommend suitable solution.
Thanks!

Chin

Hi Sean,

My design is for RGB individual LED string (see attached).

It means that the Vf are different.

Blue total Vf = 2.5 x 10 = 25V

Green total Vf =2.4 x 10 = 24V

Red total Vf = 1.6 x 10 =16 V

TPS66196 still suitable for this kind of design (different Vf connect to Vo together)?

Thanks!

 Chin

RGB LED string.docx

Hi Chin,
Actually I don't suggest to use TPS61196 for this RGB application, since TPS61196 was designed for high output volatge and current. The best way is to use three pieces of TPS61165 to independent control those RGB LEDs.
Regards
Sean

Hi Sean,

But the architecture of LED is common anode.(see attached)

Is it suitable for TPS61165 to independent control?

Sincerely,

Chin

RGB LED.docx

Hi Sean,
Any update for the discussion?
Thanks!

Sincerely,
Chin

Hi Sean,
Do you have any recommend part for the discussion of LED RGB common anode?
Thanks!

Chin

Hi Chin,

I'm sorry that I don't know which device can support this kind of design.

Regards
Sean

Hi Sean,

Thanks for the replied.

Does TPS61196 can meet our RGB LED design? (see attached again )

Any issue for the design? or it will be a malfunction ?

Thanks!

Chin

0385.RGB LED string.docx

Hi Chin,
As I have replied to you, TPS61196 is designed for hig output voltage and current, for your application, you output current is small, I don't suggest you to use TPS61196 since TPS61196 output current accurany is not very good at low current level. I also suggest you to consider using three TPS61165.
BR
Sean

Hi Sean,

Thanks for the explanation.

But if I use three TPS61165, the boost output will tie together to anode of RGB LED, but individual IFB (see attached), is it okay for the design?

Thanks!

Chin

TPS61165_x3.docx

Hi Chin,
No, you need to use each TPS61165 to power each LED string, don't tie together to anode of RGB LED, it will casue some issue.
BR
Sean

Hi Sean,

Okay.

So if our RGB LED part internal architecture is connection anode together (see attached) and we connect it as LED string in the circuit, it means I cannot find suitable TI solution for the design? Is it correct ?

Thanks!

Chin

3058.RGB LED.docx

Hi Sean,

Okay , if our design igore independ control each channel output current , please provide a suitable TI solution to me.

See attached of our LED design, please note the different VF of LED RGB string.

Or we can use TPS61181 dor the design?

Thanks!

Chin

RGB LED string__EN_Brightness.docx

Hi Sean,
How about TPS61181 on the design? Because we have another project use it.

Thanks!
Chin

Hi Chin，
Sure TPS61181 can also support your application.
Regards
Sean

Hi Sean,
Okay, so although the Vout connect together with different Vf (RGB) string, TPS61181 also can meet the design?

Thanks!
Chin

Hi Chin,
yes, but it has some infulence on the efficiency since the boost cobverter will drive the output volatge according to the maximum forward LED voltage. The difference voltahe will drop on the current sink. it will decrease the total efficieny.
Regards
Sean