MSP430F6726A: How to monitor with CPU whether DVCC has reached 3V

Hi Koki

SVS Threshold level can't set to 3V. I think ADC can be consider used monitor Vcc to 3V.

msp430f673xA_adc10_05 and msp430f673xA_adc10_15 of MSP430F673xA, MSP430F672xA Code Examples (Rev. E) are the reference

Thanks!

Hi, LI

Xiaodong LI said:

SVS Threshold level can't set to 3V. I think ADC can be consider used monitor Vcc to 3V.

- Set SVSMHRRLx to 011.
- Set AUX2LVLx to which DVCC is connected to 3V.

I thought that 3V monitoring could be realized by making the above settings and checking whether the AUX2OK register is 1.
Is my perception wrong?

Thanks,

Koki

Hi Koki

There are DVcc, AVcc, AUXVcc1 and AUXVcc2 as the power supply of F6762. AUXVcc1 and AUXVcc2  is used on auxiliary supply system. May I know which power supply channel is used on your system design?

Thanks!

Hi, Xiaodong LI

Xiaodong LI said:

May I know which power supply channel is used on your system design?

It is the primary power supply that is actually used. Also, DVCC and AUXVCC3 are supplied with the same 3.3V power supply.
I want to check if this 3.3V power supply exceeds 3V. Please tell me in detail what kind of means are available (PMM, ADC monitoring, etc.).

Thanks,

Koki

Hi, Xiaodong LI

We need to fix the problem quickly. It would be very helpful if you could give me an answer as soon as possible.

Hi Koki

If the auxiliary power supply (2 power switch) is not needed on your system. I propose you can use ADC and the ADC example code 01,15 which I talk previous to monitor Vcc voltage. I think only used DVcc and AVcc should be helpful to simplify the system design (if you don't need  2 power channel switch)

Just for your reference. Thanks!

Hi Koki

This solution msp430f673xA_adc10_05 is measure AVcc.

• ADC12INCHx (ADC Input channel) set to 1011b= (AVCC– AVSS)/ 2
• ADC12SREFx (ADC reference) set to 001b= VR+= VREF+and VR-= AVSS
  
• REF can be selected to 1.5V, 2V and 2.5V by REFVSEL.REFCTL0. In this example code 1.5V is selection.

I consider this solution:

• Connect DVcc and AVcc together
• ADC reference is (internal) REF set to 2V
• ADC monitor 1/2 AVcc which is 1/2 DVcc.
• The external connection is not needed

What do you think?

Hi, Xiaodong LI

Xiaodong LI said:

What do you think?

I'm sorry, but I confirmed with the customers that they can no longer change the hardware. Also, DVCC and AVCC are different power sources. Therefore, voltage monitoring using ADC seems to be difficult.

Xiaodong LI said:

SVS Threshold level can't set to 3V.

What is the upper limit of the voltage value that can be detected by SVS / SVM? Where can I find it in UG?

Thanks,

Koki

Hi Koki

Please ignore "SVS Threshold level can't set to 3V" because I don't have experience on SVS.

I can see the voltage value parameter of SVS can be found on MSP430F563x Mixed-Signal Microcontrollers datasheet (Rev. G)

May I know if this information is OK for your question?

Thanks!

I think it is a good idea to set up a new thread.