TPS61165: TPS61165 Maximum LED current per chain

Hi just to provide more details on intended design :

Input voltage : 5V , Vout = 18.2V , Iled=360mA max ambient temp is 50 degC. ( LCD Backlight driving 6*6 Leds - single chain )

Is TPS61165 WSON package a good fit for this application ?

Appreciate your recommendation if there are other good fit solution to drive this configuration.

Hi Dave,

1. For thermal performance, Please refer to Thermal Information of the datasheet, and TPS61165 is better.

2. Yes, they both can supply more than 400mA output current. However, it also depends on the VOUT/VIN. For 18.2V VOUT and 5V VIN, -TPS61165 is not enough.

3. I don't think it's necessary because it will be complex, larger size and higher cost. TPS61169 is proper.

BR,

Robin

Hi Robin,

Good day !

My apology , i am a bit confuse over TPS61165 and TPS61169.

With the application requirement Vin of 5V and Vout of 18.2V  ILED 360mA, based on my computation

Assuming efficient of 80% Power consumption on TPS61169 is 1.3104W     Pout = 0.36*18.2V= 6.552W

When ambient temp 50 degC

For TPS61169 , junction to ambient thermal resistance = 263.8 degC/W , so Pdmax = 0.279W

For TPS61165 WSON , junction to ambient thermal resistance = 80.7 degC/W , PDmax =0.93W

Both of the chips allowable power consumption is lower than 1.3104W. But TPS61169 will be worst right ?

Appreciate your enlightenment of how can TPS61169 fit better to our requirement ? if not is there any other better solution from TI ? for single chain driving ?

Thks & Rdgs

Dave

Hi Dave,

The efficiency is related to external inductor, diode and so on except device itself. So there won't be so much power dissipation on device.

You can apply an EVM and have a bench test.

BR,

Robin

Hi Robin,

Good day !

Below is the draft schematic for our current application.

First of all I need to confirm with you with TPS61169 , can it still fit the requirement of 18.2V 360mA driving for 6s6p backlight LED ?

Because based on my above PDmax computation , both TPS61169 and TPS61165 seems not meeting the power dissipation requirement.

I measured the TPS61169 Tcase at room temp 25 degC , it give 78 degC . Is it still ok ?