Disable Buck converter

Hi enormous,

It is possible to bypass the DCDC-converter in order to save space on your pcb, the power efficiency is bad of cource, it depends on the suppy voltage.

The pins should be connected in the following ways:

Preferred connections:

-SWITCH = open

-VBAT3V = VBAT3V_RF = VBAT1V = VDCDC = VDCDC_RF = 3.3V max

This will start the da in BOOST mode

Or, alternatively:

-SWITCH is connected to VDCDC by means of a 1K to 10K resistor, Vbat1V is grounded: 0V

-VBAT3V = VBAT3V_RF = VDCDC = VDCDC_RF = 3.3V max

This will start the da in BUCK mode

Also if there is a 1.4V supply it can be used for Vdcdc and Vdcdc_rf else the same supply as Vbat can be used up to 3.3V

The system will work just fine when with the preferred settings from either BOOST or BUCK mode but it will save a little bit of power consumption and start-up time by disabling the DCDC - converter. This is done by setting the following bits.

- DCDC_CTRL3_REG = 0x0 (bit 0 = BUCK_ENABLE = 0)

- PMU_CTRL_REG[FORCE_BUCK] = 0x1 (only in BUCK-mode the DCDC-converter can be powered-down in active mode)

Thanks MT_dialog

Hi enormous,

As i previously mentioned if there is a 1.4V available you can use this for Vdcdc and Vdcdc_rf if not you can use the same supply of 3.3V.

当应用程序开始执行da the chip, the boot rom performs some checks in order to determine if is operating under buck or boost mode. So if you bypass the converter it has to be defined in which mode the da will start and pass the checks. So when i say BUCK and BOOST mode are essentially the modes that da is going to start and not the state of the converter since its disabled.

Thanks MT_dialog