TPS65105:

Ashwini Rajesh Kamath B

Prodigy 190 points

Part Number: TPS65105

Hello People,

Greatings..!!

I have used TPS65105 in my design for my LCD voltages mentioned below

1) AVDD (V01) = 11V

2) VGL(V02) = -6V

3) VGH(V03) = 20V

4) DVDD(V04) = 3V3

5) VCOM = 3.8V

I have attached the schematic snapshot which I have designed for same voltages mentioned,

Kindly please check if my designed schematic is proper or not., If there is any corrections please feel free to mention and let me know for any feed backs.

I am confused if this circuit works or not ? Please give your feedbacks..

Thanks & Regards,

Ashwini Kamath B

over 4 years ago

0 Liaqat Khan over 4 years ago

TI__Mastermind 18550 points

Hello Ashwini,

Thank for your post but I do not see a schematics attached in your post. Please attach a schematics of your design and I will be happy to review it.

Kind Regards,

Liaqat

0 Ashwini Rajesh Kamath B over 4 years ago in reply to Liaqat Khan

Prodigy 190 points

Hey Liaqat,

Please find the schematic image below and kindly please review the same.

Thanks & Regards,

Ashwini

0 Ashwini Rajesh Kamath B over 4 years ago in reply to Ashwini Rajesh Kamath B

Prodigy 190 points

Hello Liaqat,

Thanks for the reply .. I have attached my schematics below , Please check the same.

Thanks & Regards,

Ashwini Kamath

0 Liaqat Khan over 4 years ago in reply to Ashwini Rajesh Kamath B

TI__Mastermind 18550 points

Hi Ashwini,

I reviewed and your schematics looks good overall. I have few comments as below:

- Place C434 at the emitter of Q5 i.e. on the other side of the bead.

- to start with, I would suggest to use 2.2nF/4.3K compensation as shown in the application schematics for a 5V input supply application schematics in figure 20.

- VCOM supply is shown as 3v8 but the resistor divider at VCOMIN pin would not yield this value. Just ensure that correct resistor divider values are used for whatever voltage is desired for VCOM output.

Kind Regards,

Liaqat

0 Ashwini Rajesh Kamath B over 4 years ago in reply to Liaqat Khan

Prodigy 190 points

Hello Liaqat,

Thanks alot for your review comments and I have updated same in my schematics. But i want to know what is the use of compensation pin in the schematics and will the change in values of capacitor and resistor effect in the working? Can you please explain the same.

Thanks & Regards,

Ashwini Kamath

0 Liaqat Khan over 4 years ago in reply to Ashwini Rajesh Kamath B

TI__Mastermind 18550 points

Hi Ashwini,

Compensation is used to optimize converter loop stability and transient response. The values I suggested are a good starting point and please see section 9.2.2.1.5 in the data sheet on further information on how to optimize these components once boards are back.

Kind Regards,

Liaqat

0 Ashwini Rajesh Kamath B over 4 years ago in reply to Liaqat Khan

Prodigy 190 points

Hello Liaqat,

Thanks a lot for your response ..

Regards,

Ashwini

0 Ashwini Rajesh Kamath B over 4 years ago in reply to Liaqat Khan

Prodigy 190 points

Hello,

I am using TPS65105 regulator in my project and now i am facing the issue. I want 11V in AVDD side but i am getting a voltage drop from 8V to 4.91V, whereas, VGH, VGL voltage i am not getting as expected. It is coming nearly 0v. please help me out as it is very urgent.

I want the voltages as follow,

V01 = 11V,

V02 = -6.8V

V03 = 20V

VCOM = 3.8V

Attaching the schematics for the reference

0 Liaqat Khan over 4 years ago in reply to Ashwini Rajesh Kamath B

TI__Mastermind 18550 points

Hello Ashwini,

This seems to be a duplicate of the other thread that I just responded to so I am going to close this one and we can continue our discussion in the other thread.

Kind Regards,

Liaqat

Power management

Power management forum

TPS65105: