J6EVM5777: DRA7xx Evaluation Module ( REV"D" )

Hello Mohtadi,

SMPS6 - SMPS9 are assigned as follows:

SMPS6 ---> vdd_gpu = 1.06V

SMPS7 ---> vdd = 1.15V

SMPS8 ---> vdd_iva = 1.06V

SMPS9 ---> vdds18 = 1.8V

there might be slight variation in SMPS6-8 voltages due to several reasons, but these values should be enough for the short-circuit search.

Please let us know if you find the reason for the issue.

Regards,

Stan

Hello Stan ,

I found this values :  

Vdd_gpu ---> 1.06V

Vdd_core---> 1.15V

Vdd_Iva   ---> 1.09V

Vdd_18  ---->  1.8V

When I measure the continuity between Vdd_core and the Gnd I get a continuity  but when I invert the polarity of the metrix (metrix + -> GND and metrix (-) -> Vdd_core) I gets nothing. When I cheked this probleme I hat is due to the low impedance in this output.

Does this mean that my circuit (U45) is destroyed?

Thank you in advance.

Regards,

Belghith Mohtadi

Hi Belghith,

You had measured 1.15 V which is exactly what is required. I don't beleive it is the PMIC.

You can try to desolder L18 which will disconnect PMIC from its loads on vdd_core and measure continuity again on both sides.

Are all other voltages to the display board correct? Does the backlight light up? Is your OS/software configured to use the display?

Regards,

Stan

Hi Stan ,

I have mistake :

Vdd_core=1.06 V ,

Is that mean we have a probleme at U45 ? 

I will check again the others Voltage to the display and the software.

best regards,

Belghith Mohtadi

Hi Stan, 

The voltage to the display are good and we do not have any probleme there .

We have update the software again and we don't have any display mode even the screen is power off. 

I just need to check if the vdd_core which the voltage is at 1.06V and not 1.15V. Is this mean we have  a probleme at the U45.

Thanks.

best regards,

Mohtadi