TPS65150 test condition VCOM current

Sebastien.M

Other Parts Discussed in Thread: TPS65150

HI,

We are using the TPS65150 and we are wondering what is the maximum output current that the component can provide on the VCOM signal?

We used a configuration to get on Vs 9.3V, VGL -10V, VGH 15V and VCOM 4V.

In a test, we want to know if the component can provide 100mA dc on the VCOM pin. To check it, we add a 40Ohm charge resistance on the VCOM pin. The VCOM signal drop to 1.21V. The Vs, VGL and VGH voltages are still correct. In the datasheet, it seems that the TPS65150 can provide at least 150mA.

Do you have any idea why we get this result?

Thank you in advance,
Best regards,

Sébastien

over 9 years ago

0 Ilona over 9 years ago

TI__Expert 8010 points

Hello Sebastien,

Have you done this test with a load on VGH/VGL/VS as well? What is the current limit set at your power supply?
Meanwhile I will check your request in the lab.

Thank you.
Best Regards,
Ilona

0 Sebastien.M over 9 years ago in reply to Ilona

Prodigy 130 points

Hi Ilona,

I did not test with a load on VGH/VGL/VS. The current limit of the power supply was 3.5A.

Thank you.
Best regards,

Sébastien

0 Ilona over 9 years ago in reply to Sebastien.M

TI__Expert 8010 points

Hello Sebastien,

The device cannot start in full load (maximum load during startup ~ 50 mA).
You will have to turn on the supply first and wait until all stages are in regulation and then you can add a load on VCOM.

Can you check if it works if you connect the load after the startup?

Best Regards,
Ilona

0 Sebastien.M over 9 years ago in reply to Ilona

Prodigy 130 points

Hello Ilona,

After the startup, I load a 40Ohms resistor on VCOM and the VCOM signal did not change.

Thank you.
Best regards,

Sébastien

0 Ilona over 9 years ago in reply to Sebastien.M

TI__Expert 8010 points

Hello Sebastien,

Can you check whether you can load VCOM with a small current ~ 20-50 mA?
Can you share your schematic for analysis?

Thanks.
Best Regards,
Ilona

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TPS65150 test condition VCOM current