Vref of VSENSE block in MM9Z1_638

[shlee8467]

Hi.

I cannot find Vref value of VSENSE block in its datasheet.

So, I tryed to calculate the Vref by comparing the analog input voltage with the ADC value.

But it changed depending on the input voltage such as 1.6321v, 1.6430v 1.649v and the value looks strange.

I have to use PTB0~PTB3 port.

Please let me know how I can calculate the correct voltage with  or without Vref.

Thanks,

[TomasVaverka · Accepted solution]

Hi Seunghwan,

There is no need to know the Vref value of VSENSE.

The measured selected (based on VSSEL and VSEx bits of the GPIO_VSENSE register) voltage can be calculated as follows:

1. VSENSEx: V = ACQ_VOLT[15:0] x VSxRO

2. PTBx: V = ACQ_VOLT[15:0] x PTB0-4VRES

Best regards,

Tomas

[shlee8467]

I really appreciate it. Tomas.