• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 78 subscribers
  • Views 1169 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.

Internal connection of MSP430F6433IPZ.

Hidetaka
Expert 1080 points

I have four questions about the internal connection of MSP430F6433IPZ. 

Does someone answer and do you get?

(1) DVCC1 (pin 25), DVCC2 (pin 64), and DVCC3 (pin 89) have prepared a three-place pin, in order to secure internal current distribution.
For that reason, as for these three pins, the inside is connected in common.
Is this right?

(2) The inside is connected in common DVSS1 (pin 26), DVSS2 (pin 63), and DVSS3 (pin 90) similarly.
Is this right?

(3) Moreover, AVSS1 (pin 12), AVSS2 (pin 15), and AVSS3 (pin 83) are similarly connected inside.
Is this also right?

(4) DVSSn (digital GND) and AVSSn (analog GND) are not directly connected inside.
Is this right?

Regards, Hidetaka.

  • 0
    Guru 74080 points

    Hideka, wouldn't it have been enough to ask this question once? Or make one question out of it?

    OCY answered it here:

    Dennis

  • 0
    Guru 227245 points
    DVSS(x) and AVSS(x) are not directly connected internally. But they are indirectly connected through clamp diodes. So if you do not power AVCC but power DVCC, AVCC will be indirectly powered through these diodes. Which might be sufficient for operation, even though performance (precision, SNR) won't be as good.

    For DVCC and DVSS, it is recommended to connect all pins. Also blocking capacitors and maybe even a small storage capacitor should be placed at every DVCC.

    For AVSS, connecting one is usually sufficient, as the analog side doesn't draw significant currents. AVSS shouldn't be connected to DVSS. It should be routed separately to the supply GND point, so digital return currents do not cause a ripple voltage on the analog GND.

    AVCC should not be connected directly to DVCC too. While it should be sourced form the same voltage regulator as DVCC, there should be a low-pass filter between the two. Like a 10 to 100Ohm series resistor between DVCC and AVCC, and a 100nF ceramic/10µF Tantalum capacitor combo from AVCC to AVSS.

**Attention** This is a public forum