Omit Analog supply caps on MSP430?

[DTJ]

A silly question................


I've got a design using an MSP430F5359.

I'm not using the analog inputs at all.


I'm tight on space & cost - can I safely omit the filtering caps on the AVCC pin?

Should I still need to connect the 3V supply to the analog AVCC pin (I suspect yes..)


Cheers.

[ogden]

I'm tight on space & cost - can I safely omit the filtering caps on the AVCC pin?

You can omit AVCC caps if you rely on DVCC caps. Just connect AVCC and DVCC together. Whatta product you have if you cannot afford extra 0.001$ for few SMD capacitors?

Should I still need to connect the 3V supply to the analog AVCC pin (I suspect yes..)

You must supply AVCC even if you (seemingly) don't use analog parts of uC. Excerpt from datasheet: "A maximum difference of 0.3 V between AVCC and DVCC can be
tolerated during power up and operation"

[DTJ]

I'm tight on space & cost - can I safely omit the filtering caps on the AVCC pin?

You can omit AVCC caps if you rely on DVCC caps. Just connect AVCC and DVCC together. Whatta product you have if you cannot afford extra 0.001$ for few SMD capacitors?

Hahaha, cost is not an issue - space is a premium!


Thank you for your assistance. I'll hook the AVCC + DVCC together and let them share some caps.