TPS61169: LED lifetime calcuration

Yuto Hori

Prodigy 400 points

Part Number: TPS61169
Other Parts Discussed in Thread: TPS61042

Hi team,

Customer considers replacement from TPS61042 to TPS61169.

As for TPS61042, we can calcurate LED lifetime by summing up the PWM ON times.

But for TPS61169, we cannot calcurate the lifetime due to change in volatage and current value to LEDs by FB pin.

How should we calculate LED lifetime when using TPS61169? Do you have any materials for this?

Your support is highly appreciated.

over 1 year ago

0 Patrick Yao over 1 year ago

TI__Mastermind 29220 points

Hi Yuto,

May I know which formula will you apply to calculate the LED life time of TPS61042?

Patrick

0 Yuto Hori over 1 year ago in reply to Patrick Yao

TI__Prodigy 400 points

Sorry for the wrong explanation, customer requests formula to calculate for both of TPS61042 and TPS61169.

They would like to know how long LED lifetime is affected by changing devices. Do you have such a formula?

0 Jared Zhou over 1 year ago in reply to Yuto Hori

TI__Genius 17965 points

Hi Yuto,

Our expert is out of office and will reply to your questions once coming back. Thanks for your patience.

BR, Jared

0 Patrick Yao over 1 year ago in reply to Yuto Hori

TI__Mastermind 29220 points

Hi Yuto,

Unfortunately we don't have such formula, and in my understanding, the LED lifetime will also vary with different manufacturers, so I would suggest customer ask their LED supplier for this information instead.

BTW, may I know which of your customer is asking and what is their end equipment as well? Thanks

Patrick

0 Yuto Hori over 1 year ago in reply to Patrick Yao

TI__Prodigy 400 points

Hi Patrick,

Is it even difficult to see the difference between TPS61042 and TPS61169 for the same LED?

Customers EE is HVAC controller.

Best regards, Yuto

0 Patrick Yao over 1 year ago in reply to Yuto Hori

TI__Mastermind 29220 points

Hi Yuto,

We don't have a reference formula so it's hard to say whether the dimming mode will influence the LED lifetime.

Patrick

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

Power management

Power management forum

TPS61169: LED lifetime calcuration