• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 62 subscribers
  • Views 212 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Original question:

TPS65100 Power Up / Start Up Problem

TPS65100: TPS65100 Power Up / Start Up Problem

Anwej Alam21
Intellectual 375 points
Part Number: TPS65100

Dear Sir,

We are using TPS65100 for  Powering  LCD where we need AVDD=10.4V, 400mA, VGH = 16V, 4mA,  VGL = -7V, 4mA, and VCOM = 3.6V. We are facing some problems with the below-attached schematic, Some time start and build all power supplies as normally required on Power up, but sometimes do not start and build up any required power rail.

Please suggest any corrections to be made to solve the above issue. 

  • 0
    TI__Mastermind 18550 points

    Hello,

    I suggest to remove C22 and connect pin 15 of the device to GND so that it is used in charge pump doubler mode.

    Your current schematics is using the device in tripler mode and it may not be able to regulate to 16V in tripler mode and hence shutting down.

    Kind Regards,

    Liaqat

  • 0 in reply to Liaqat Khan
    Intellectual 375 points

    Dear Liaqat,

    Thanks for your response. your observation was correct regarding C22 and PIN#15 for double mode. by changing your suggested modification in the circuit, Now we are getting 16V at VGH, earlier it 20V.

    The random shutdown of the Power rail is not solved yet, We found that the current of AVDD(10.4V) is limited by 310mA, beyond this current Voltage is going drop by increase even 1-2mA.

    That is the reason, it's going into shutdown due to the current issue, At the starting peak current also plays a role to continue this problem.

    We required a continuous current of 400mA and a peak current of even more than 400mA for a few hundreds of milliseconds. 

    any suggestion for increasing current delivery capability since this TPS65100 has current capability even more required?

    Thanks in advance. 

  • 0 in reply to Anwej Alam21
    TI__Mastermind 18550 points

    Hello,

    output load current is limited by boost switch current limit.  So to achieve higher current, voltage conversion ratiowill likely need to be smaller by either increasing input volatage (VIN), or reducing output voltage AVDD.

    Kind Regards,

    Liaqat