Usage of TPS61169

fabricepeden

Intellectual 545 points

Other Parts Discussed in Thread: TPS61169

Hi everybody,

I'm using a TFT screen from winstar. To control the backlight, I'd like to use the TPS61169.

Backlight's LEDs are made as follow :

9 lines of 3 LEDs. The global is current is 180mA (20mA per lines).

Rset = 240mV/0.18 = 1,13R

The TPS61169 will be supplied with 3V3.

On the other side, I don't understand how is provided/calculated Vout. In the datasheet, Vout is specified from Vin to 38V. Is Vout determined automatically according to the number of LEDs which must be supplied ?

Thank you,

Regards

Fabrice Péden

over 9 years ago

0 Randy Dahl over 9 years ago

TI__Intellectual 2090 points

Hi Fabrice

The TPS61169 will automatically adjust the boost output voltage based on the number of led in a string, the led forward voltage and the current in the LED string. It is important to note that the actual current in each LED string will vary due to mismatch in the led forward voltage.

Best regards,
Randy

0 fabricepeden over 8 years ago in reply to Randy Dahl

Intellectual 545 points

Hi Randy,

Thank you for your answer, it is what I was thinking.

Regards,

Fabrice Péden

Power management

Power management forum

Usage of TPS61169