VDD1P5 to 1.5 V in Buck mode. This connectivity framework code can be found on the KW41 SDK examples
folder (SDK_2.2_MKW41Z512xxx4\boards\frdmkw41z\wireless_examples\smac\connectivity_test\bm\iar).
/* Default DCDC Mode used by the application */
#define APP_DCDC_MODE gDCDC_Mode_Buck_c
#define APP_DCDC_VBAT_MONITOR_INTERVAL (50000)
/**Configure the DCDC parameters though this const variable**/
const dcdcConfig_t mDCDCBuckDefaultConfig =
{
.vbatMin = 1800,
.vbatMax = 4200,
.dcdcMode = APP_DCDC_MODE,
.vBatMonitorIntervalMs = APP_DCDC_VBAT_MONITOR_INTERVAL,
.pfDCDCAppCallback = NULL, /* .pfDCDCAppCallback = DCDCCallback, */
.dcdcMcuVOutputTargetVal = gDCDC_McuV_OutputTargetVal_1_500_c,
.dcdc1P8OutputTargetVal = gDCDC_1P8OutputTargetVal_1_800_c
};
At the hardware initialization, call DCDC_Init function from the DCDC.c connectivity framework and the initialization, including the
ADC and timer setup, is executed.
//Init DCDC with VDD1P8 @ 1.8V
DCDC_Init(&mDCDCBuckDefaultConfig); // call to DCDC SDK Framework
4.2 Configuring Continuous mode
The DC-DC converter operates only in Continuous Mode when the MCU is in RUN, WAIT, and STOP modes. The DC-DC
converter may operate in Continuous mode or Pulsed mode through register selection when MCU is in VLPR, VLPW, and VLPS
modes. Continuous mode is not available for LLSx and VLLSx modes.
Depending on the use case and the low-power mode usage, it may be more efficient to select continuous mode rather than pulsed
mode. For current up to 0.5 mA, the recommendation is to measure the loading dynamics of the application to verify which mode
has better performance. Above 0.5 mA, the DC-DC must be configured for Continuous mode.
4.2.1 Target voltage adjustment
In Buck and Boost modes, the DC-DC converter output voltages are programmable. To adjust the target voltages of VDD_1P8
and VDD_1P5 in Continuous Mode, follow the below steps:
NXP Semiconductors
DC-DC converter software setup
MKW4xZ/3xZ/3xA/2xZ DC-DC Power Management, Rev. 3, 04 June 2021
Application Note
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