CCS/CC2642R: How to enable/disable Alternative DC/DC setting at run time?

As far as I now the only option is to set if you want to use DCDC in the CCFG and hence set this when booting. 

Could you elaborate some on the background for the question? 

Hi Mehul,

It sound like it is the "SET_CCFG_MODE_CONF_DCDC_ACTIVE" define you are actually look at, correct?

There is DriverLib functions available to switch between the Global LDO and DC/DC but to fully use this you would also need to modify the Power DPL file as this will try to re-enable DC/DC if possible to get the lowest possible power consumption.

In the case where the internal DC/DC is not used, you plan to use the Global LDO or an external source? 

Thanks for the reply. Can you give us some example on what you are suggesting?

In case we do not use internal DC/DC, we plan to use external source.

Do you here mean "external regulator mode" or something else? Please elaborate some on how you plan to power this. 

We will go with the external converter on one of the hardware. It already had an existing 1.8V rail that was backed by a power store used elsewhere on the other hardware module.

I assume that you in this case use the harware setup shown in 9.2 in http://www.ti.com/lit/an/swra640c/swra640c.pdf. If that is the case, note that the chip will reset if the voltage drops below ~1.77 V which would require that you use above 1.80 V. 

Also note that the DCDC is turned off automatically if VDDS is below 2.1 V. 

Thanks for your reply. I need more clarification to be sure enough. I am referring to http://www.ti.com/lit/an/swra640c/swra640c.pdf document below while mentioning about specific section.

So, we have 3 different hardware which intend to use CC2642:

• Hardware A: Uses internal DC/DC converter mode (as per section 9.2), VDDS > 2.1V
• Hardware B: Uses global LDO mode (as per section 9.3), VDDS < 2.1V
• Hardware C: Uses External regulator mode (as per section 9.4), VDDS = 1.8V

Our primary goal here is to have one single common firmware for all above 3 hardware having a different Power Supply configuration (all 3 mentioned in the section 9).

As per your last statement above, "the DCDC is turned off automatically if VDDS is below 2.1 V". So, if we have below configuration in our common firmware in all above hardware A, B & C, how the hardware will behave?

#ifndef SET_CCFG_MODE_CONF_DCDC_RECHARGE
#define SET_CCFG_MODE_CONF_DCDC_RECHARGE                0x0        // Use the DC/DC during recharge in powerdown
#endif

#ifndef SET_CCFG_MODE_CONF_DCDC_ACTIVE
#define SET_CCFG_MODE_CONF_DCDC_ACTIVE                  0x0        // Use the DC/DC during active mode
#endif

 With configuration above in the firmware, are below statements correct? Whether the CC2642 disables internal DC/DC automatically and selects Global LDO OR external regulator mode based on hardware?

• Hardware A: Internal DC/DC enabled as VDDS is > 2.1
• Hardware B: Global LDO is enabled automatically by CC2642 as the hardware is configured as per section section 9.3 & VDDS < 2.1V
• Hardware C: External regulator is enabled automatically by CC2642 as the hardware is configured as per section 9.4 & VDDS is 1.8V

If above is not correct, what should be the configuration in the firmware then?

Another question. With below statement in the firmware, will CC2642 VDDS BOD level 1.8V for Hardware A and 1.65V for Hardware C automatically with internal DC/DC settings enabled in the firmware mentioned above? 

#define SET_CCFG_MODE_CONF_VDDS_BOD_LEVEL               0x1        // VDDS BOD level is 1.8V (or 1.65V for external regulator mode)

If all of above understanding is correct with your confirmation, we can say that configuring internal DC/DC in the firmware shall work for all Hardware A, B and C as CC2642 internal DC/DC is turned OFF automatically which in turn enables global LDO OR external regulator.

Hi, gentle reminder to provide a reply.