MSP430F5310: MCU power dissipation

Hi Jonathan,
You can find more information about power disipation in the datasheet's 5.6 Thermal Resistance Characteristics section:

Best Regards,

Diego Abad

Hi Diego,

Thanks for your response

my question was on what contributes to the power dissipation mainly

and it's formulae

Can you help with this please

Regards

Jonathan Kabangu

Hi Jonathan,
Power dissipation in the MSP430 will require things like Thermal resistance  and Junction temperature. Let me see if I can a formula from my team members.

Best Regards,

Diego Abad

Hi Diego,

yes the formulas will be helpful and a quick example using it too

Thanks

Jonathan Kabangu

The question is about power dissipation but the equation is for temperature. So...

Power dissipation is tiny. Less than 20mW. (5.4, active mode supply current) Even with the fairly high junction to ambient thermal resistance (varies between packages), the temperature rise is still tiny. 0.02W * 63 C/W
So a non-issue.

Hi David,

the initial question was on what’s contributing to the power dissipation 

core,switching frequency,GPIO’s ….what else ?

in other words I’m looking for formulae’s to apply when do doing worst case circuit analysis by calculation step by step

I hope this makes it more clear ,Thanks 

The data sheet shows the active mode supply current for the MSP430. This doesn't include current required to drive external devices since TI has no clue what that is. 

The MSP430 is such a low power device that it will require great effort on your part to get it hot.

Don't over-complicate things. Simply measure and sum all the currents going into the device * their voltages and subtract any current * voltage leaving the device.

Hi Keith/David,

thanks for the response and insight,

formulae wise would you say this this is the correct one:

Total power dissipated=VDD's*IDD(core)+CL*VDD^2*Fsw(switch power)+Voh*Ioh(GPIO)

Jonathan Kabangu

I see I guess the drop inside the MCU

will be VCC-VOH e.g 3.3-2.9V=0.4V

0.4V*IOH??