MSP432E401Y: ADC for MSP432E401Y

albgarc2014

Part Number: MSP432E401Y

Hi TI!!!

I need to measure the voltage of 8 DC sources with maximum value of 24V. For this I will use a voltage divider with two resistors of 100k and 15k, so I take a sample of approx. 3.13V when the voltage to be measured is 24V (maximum), please see the schematic.

My question is if I can take the voltage sample directly from the resistive divider to the MSP432E401 pin or should I put an operational amplifier (between the resistive divider and the MSP432 ) with gain = 1 to acquire the voltage sample from a low impedance source?

Another question:
For the 8 input pins of the ADC I plan to use PD0,...PD7. There is no problem with this 8 pins to read the analog voltage samples, right?

over 2 years ago

+1 Charles Tsai over 2 years ago

TI__Guru**** 191906 points

Hi,

albgarc2014 said:
My question is if I can take the voltage sample directly from the resistive divider to the MSP432E401 pin or should I put an operational amplifier (between the resistive divider and the MSP432 ) with gain = 1 to acquire the voltage sample from a low impedance source?

Should be fine as long as you meet the the ADC source impedances specified in the datasheet and you have proper filter capacitor. An op-amp would certainly help to prevent loss of signal transfer. Take a look at these articles.

https://www.ti.com/lit/pdf/spna118

https://electronics.stackexchange.com/questions/559532/should-i-buffer-my-analog-input

albgarc2014 said:
For the 8 input pins of the ADC I plan to use PD0,...PD7. There is no problem with this 8 pins to read the analog voltage samples, right?

I don't see a problem if the corresponding channels are what you want to use for sampling. For example PD0 is mapped to AIN15. See below.

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MSP432E401Y: ADC for MSP432E401Y